95 Comments:

 Anonymous said... At Monday, July 14, 2008 2:26:00 PM PDT

can you tell me where you got your capacitors?

 

 Jim Warholic said... At Monday, July 14, 2008 3:23:00 PM PDT

This post has been removed by a blog administrator.

 

 Anonymous said... At Wednesday, July 30, 2008 2:23:00 AM PDT

I have a 2e generation G5 iMac (with the ambient light). I have the same problems, but do you think it has something to do with the capacitors as well?

My problems started exactly on the day when it became 3 years of age, but because it is the second generation it does not fall in the program.

from Holland,

Willem

 

 Anonymous said... At Wednesday, July 30, 2008 2:24:00 AM PDT

I have a 2e generation G5 iMac (with the ambient light). I have the same problems, but do you think it has something to do with the capacitors as well?

My problems started exactly on the day when it became 3 years of age, but because it is the second generation it does not fall in the program.

from Holland,

Willem

 

 Jim Warholic said... At Wednesday, July 30, 2008 8:14:00 AM PDT

The only way to tell for sure, is open the case and look closely at the capacitors themselves. If there is any bulging at all on the tops, it is very likely that those caps are of the same vintage as the first generation.

Take it in to a local Apple store, if you have one in your area, and have the Genius Bar folks take a quick look at it on the inside. They will give you an estimate of the repair cost and what is likely required for the hardware repairs.

By-the-way, I believe mine is considered a second generation iMac. The serial number of mine fell within the serial number range. The Apple folks did tell me that if I had problems a couple of months earlier, the iMac G5 Repair Extension Program for Video and Power Issues would have covered my particular model. Maybe that means I have a first generation model. Not sure on that though. That wasn't made completely clear. I'm not sure what exactly the differences are between first generation PPC iMac G5 and second generation PPC G5 iMacs.

Mine does have the ambient light sensor, but it only had 512KB of memory, 150 GB Hard Drive, 20 inch display monitor, 1.8 GHz PowerPC G5 processor, and OS X Panther of which I upgraded to OS X Tiger Version 10.4.11.

Note: I also upgraded the memory to 1 GB myself.

 

 robouden said... At Monday, August 4, 2008 1:16:00 AM PDT

I can only get 2200uf and 10 volt at the local stores here. Would those be fine too?

regards
rob oudendijk

 

 Jim Warholic said... At Monday, August 4, 2008 1:35:00 PM PDT

I don't think I would go and change the values of the capacitors by more than 10% for the MFD rating. In my opinion, the original circuit design would be compromised too much with having a substantially higher or lower rating on the capacitor MFD rating. Without having a detailed circuit board schematic of the motherboard in hand, and knowing some of the circuit components interactions, you can't be sure that installing drastically different capacitance won't affect something else in a way that you might not be aware of.

Capacitance is a measure of the amount of electric charge stored (or separated) for a given electric potential. For example: Higher rated uf capacitors typically take a longer time to build up a DC stored charge. This slower build up of the charge could affect other electronic components in those areas of the circuit board.

Let's say for example that the motherboard has a certain amount of time from when it goes to sleep in the video mode, and also the wake up cycle has a preset amount of time to bring the display alive at full voltage, when the mouse is moved which activates the wake up screen mode. If the higher uf rated capacitors take longer to build up a charge, then it could affect the display when it is waking up from the sleep mode or even shutting down to the sleep mode. In this case, the capacitors actually take longer to discharge. Using higher MFD capacitors could also damage something else in the computer. These are the issues to contend with when using higher uf rated capacitors. On the other hand, installing lower uf rated capacitors has the opposite problem that they will not filter the AC properly and provide a level of DC voltage with no ripple. Think of a capacitor as a device that filters out AC and provides a steady DC voltage. The symptoms of installing lower uf caps would be be the same type of problem as is the case now with the bad capacitors. In fact, placing lower uf rated capacitors is like installing bad capacitors to begin with. The under rated caps do not filter as well, or don't filter to the specifications of the original capacitors.

Note: Many capacitors today are built to a 1%, 2%, 5%, 10%, or 20% tolerance on their ratings. I suspect the ones I used were either +/- 10% or +/- 20% tolerance rated. So, if you go up higher on the uf rating to begin with, you could be way too high on the overall capacitance rating.

If you can't find the capacitors locally, I suggest you order online from some electronics supplier company with the correct ratings and physical size of the capacitors. Measure your height and diameters to be sure you are ordering the correct ones. These capacitors shouldn't be too expensive to buy. I would think somewhere around 0.25 to 0.50 each. I got all my capacitors for under $10.00 total.

 

 Willem said... At Thursday, August 7, 2008 10:57:00 AM PDT

Hi Jim,

Well if you have the ambient light sensor I am sure you have second gen. Mine also has this serial number in the rage, but that does not matter.
I am glad i didnt distroy the iMac already, and keep you infomerd if it worked alright.

Willem

PS a print button in your article would be a nice extra ;)

 

 Jim Warholic said... At Tuesday, August 19, 2008 1:15:00 AM PDT

Just an update on the cost of new capacitors.

After doing some research online, I see that the capacitors are a little more expensive to purchase than previously thought. I think they are more likely to be $1.00 to $1.25 each for brand new ones. You might be able to find them cheaper in bulk, but they might not be of the same quality, temperature ratings, or life expectancy that you really need to install on the motherboard for the long term computer usage.

 

 Vincent said... At Friday, August 22, 2008 7:05:00 PM PDT

Great blog! Colleague told me about the industrial espionage that's resulted in bad capacitors all over planet Earth. He's also very handy with the soldering gun, but he's never mentioned using lead-free solder.

I have an iMac G5 20" (don't think it has the ALS) with two bad capacitors, but I don't know which two. Genius at the Apple store told me my iMac didn't qualify for that recall work since the power supply's work (he heard fan noise).

Any thoughts on how to take apart this machine so I can access all of the capacitors on the logic board? I may still give the Genius Bar another shot just the same.

I'm bookmarking this blog!

Vincent

 

 philtesone said... At Sunday, August 31, 2008 9:43:00 PM PDT

This post has been removed by a blog administrator.

 

 Anonymous said... At Wednesday, September 3, 2008 8:08:00 PM PDT

Please consider adding a warning to use a wrist strap or other ESD protection when working with the logic board. I didn't see any wrist straps on the YouTube videos.

No use replacing bad caps if you zap some other component with ESD.

 

 Jim Warholic said... At Wednesday, September 3, 2008 9:59:00 PM PDT

That's a good point about concern for static and properly grounding yourself prior to working on the computer.

Note: A grounding strap helps reduce static and maintain the same ground (electrical potential) as anything that is touched. It is not absolutely required to use a grounding strap, though a clip-on wrist ground strap is not very expensive and very easy to use.

I use grounding straps occasionally, but here is what I do most of the time when I work on computers or other electronic devices. First off, make sure you unplug the computer from everything. Once you have the computer on the desktop, then make sure you touch the main chassis of the computer prior to touching any of the electronic components. This establishes the same electrical potential between yourself and the computer being worked on. Additionally, as you use various tools, including the soldering iron, this could also impart a static charge to the circuit board. There are very expensive soldering stations that could be used, however, a good quality plugin soldering iron (designed for lead-free soldering) and if you use some basic common sense in handling the tools, and not shuffling your feet on the carpet, or even better yet, not working on a carpeted area, are some of the best practices to apply when working on the electronics of your computer.

 

 margaret said... At Tuesday, September 9, 2008 10:56:00 AM PDT

I have a G5 that is approximately 5 years old. It does not qualify for any of the recalls but it sounds like the same problem. The certified repair place is telling me that it needs a new motherboard and will cost approximately $800 to repair. I have no way of knowing if I am getting completely taken or if this is a standard cost for a 5 year old computer. I hardly used the machine but all my photos are stored on it so I feel like I have no choice but to repair. What do you recommend?

 

 Jim Warholic said... At Tuesday, September 9, 2008 7:45:00 PM PDT

Hello Margaret,

The price is probably a fair and accurate amount for the G5 repair fix. G5 Mother boards are expensive, plus the time involved in the actual replacement is involved.

Other readers have written to me and asked if I would be interested in repairing their computer for them in regards to the capacitor problems. I mentioned to them also that the process is quite involved, and difficult because of the design of the motherboards today using the high melting point temperature required for the lead free solder. One person that emailed me said that he was going to give it a try himself. He mentioned that he had nothing to lose.

You didn't mention in your comment if the certified repair center said the problem was with the capacitors or something else was broken on the mother board.

If you just need to get the files and pictures off the Mac, you could simply pull out the hard drive and place it on a bench with a USB adapter plug, plugged into the hard drive on the bench, and another computer to download the files to another storage device. A USB to parallel hard drive socket adapter interface plug (also known as IDE plugs and Parallel ATA (PATA) plugs) is about $25.00.

To do this does however require removal of the old hard drive from inside the Mac, and plugging in the USB to parallel adapter on a desk top.

If I get a chance, check back here and maybe I'll post a new posting with a picture of how to do that. It's actually pretty simple to do.

If you (or anyone) would like to contact me directly, feel free to use the email form below, or the email link on the top right of my web page, or go to wow.jimwarholic.com for more contact information.

 

 Anonymous said... At Sunday, September 28, 2008 2:58:00 PM PDT

Hey Jim,

I just wanted to thank you for your great article on the G5 imac cap problem. Using your recommended specifications for replacement I have successfully repaired, and revived a G5 iMac logic board. I replaced all the caps in the same manor as you and am so happy to report that the system is absolutely stable and the temps ARE in fact lower than before I began to experience the problem, the freezing/crashing problems. (I only had 3 that were bulging but I replaced every one of them anyway)

Thanks again Jim!!

P.S. this was my first attempt to solder on a mobo. I'd like to think I'm technical enough to handle a project like this and was really excited to finish the repair and find success!

 

 Anonymous said... At Thursday, October 2, 2008 6:15:00 PM PDT

I know nothing about fixing things. I did want to log on to say my iMac G5 just died. The first sign was kernel panics. It was three years two months old so AppleCare had ended two months earlier. After I found this site I opened my iMac to discover bulging capacitators. It is a first generation iMac.

 

 Allstonpowers said... At Friday, October 3, 2008 10:00:00 PM PDT

This post has been removed by a blog administrator.

 

 Jim Warholic said... At Friday, October 3, 2008 11:12:00 PM PDT

Hey Allston,

Congratulations on your successful motherboard repair. More powers to you. Pardon the pun...

I'm glad to hear that my (our collective) documentary has made a difference for those that are willing to take a chance, learn, and discover that they can do something themselves to make a difference, even if that difference is just a small part of their life.

I think your comment on requiring "some force" is quite accurate for pushing out the leads in my Apple case that broke off from the old capacitors, or in your motherboard case, cleaning out the holes to make them large enough for the new capacitor leads to be inserted in the mobo.

Keep the comments coming everyone and keep the documentary alive.

 

 mysticmcj said... At Thursday, October 16, 2008 10:28:00 AM PDT

I will be attempting this soon. I've just encountered this problem myself... My iMac G5 was randomly locking up and kicking the fans on, so I opened it up, and alas, bulging capacitors.

I've seen another method that involves cutting the old capacitor out with side cutters, and soldering to the wires that remain - which seems a bit simpler than trying to desolder the cap.

I'll update when the caps arrive - I'm not ready to get rid of my G5 yet!

 

 Jim Warholic said... At Thursday, October 16, 2008 5:10:00 PM PDT

Hello Mystic,

I agree with you about not ready to get rid of my G5 yet.

That's an interesting idea about soldering to the old leads themselves. However, if you try to do this on all the capacitors, I think it is going to be difficult to be able to physically fit the new capacitors in the same locations.

My personal opinion is you will get a better connection if you solder the caps directly to the motherboard.

Good luck. Keep our readers posted.

 

 John Doe said... At Thursday, October 16, 2008 6:06:00 PM PDT

Hi Jim.

First of all, many thanks for this site and work involved.

I just might have got struck by this issue as well, my iMac G5 1.8 1-st gen just died on me, period.

It started two months ago with problems to boot or chime, and when it finally did go on, it worked for a month or so.

Now, after shutting my iMac down I can not boot it anymore. At all.

Seems like the capacitors problem, doesn't it?

But the thing is - all the caps look perfectly normal, nothing gone bad, no leakage.

The serial number of my iMac puts me right in the middle of the group with faulty caps - that's a fact.

So my question is: can this still be the caps issue if they all seem to look perfect even though the serial number says they should be the bad ones?

How smart would it be to swap all the caps myself (I can manage) without any tech diagnose etc.?

PS I have to say I've seen many computer parts with bad caps, and there always were signs of it. Caps were swollen, were leaking, or the cap top was caving in - revealing either leakage or emptiness of a bad cap.

So this case seems a bit tricky to me. Almost like a trap to waste my time.

Cheers.

 

 Jim Warholic said... At Thursday, October 16, 2008 6:12:00 PM PDT

Dear JD,

Thanks for the message about the website.

I too have had experience with caps in the past being bad. However, I missed the subtle differences of the ones that were bad on mine. The Genius Bar folks at Apple quickly pointed the bad ones out to me. The bulges were ever so slight on the tops, and there were others with no bulges at all that were indeed dried out. The only signs were after removing some of them, I saw signs of electrolytic juice on the circuit board ever so slightly.

The other possibility for you is a bad power supply with bad caps too. I haven't taken that one apart yet.

Good luck,

Jim

 

 mysticmcj said... At Monday, October 20, 2008 6:21:00 AM PDT

So as a follow up - I ended up ordering caps from computek, and chopping the old capacitor out. I was lucky in that this one was located in a place that made this easy, and had plenty of room for installation...

Everything went smooth. I'm horrible at soldering - I left a huge hole in a board when I tried to mod my first PSX - and I was able to pull this off without any problems whatsoever, so if I can do this, I'm sure others can as well. Don't write off those G5's - Hang on to em!

I'm running a 24 hour test right now, but it WORKS and it seems to work VERY well.

I couldn't recommend this method for anyone who wants to replace all of the caps (there's not enough room to work on that side of the mainboard) but for my case it was good. When I have some more time, I'll probably replace the rest.

Thank you so much for all of the info - I could have never done this without this site.

 

 Dave said... At Sunday, October 26, 2008 1:36:00 PM PDT

Thank you everyone for leaving comments, it's reassuring that this is indeed possible. I was givin a maxed out iMac G5 with a capacitor problem. Opened the back and noticed 2 that were bulging. While I move forward i'm going to take pictures of the process and post them on a blog or website so others can learn from what were trying to do. Just a quick question before I dive right in though. What components do i have to remove to completely remove the logicboard? Everything? Or can I just take out screws for the mainboard. Any help would be appreciated. Thanks!

Dave.

 

 Jim Warholic said... At Sunday, October 26, 2008 7:39:00 PM PDT

I removed the hard drive, CD/DVD writer, and the right fan cover. I also removed the power supply in order for the mother board to be easily removed. Follow the Apple procedure for removing the power supply. By the way, I also removed the memory boards from their slots. It's easier and safer to not have these items attached.

One other point, I think I had to remove a couple of other small items on the motherboard in order to get a cable that was fished through the circuitry. The bracket that holds a wireless AirPort Extreme Card, if you have that option, (I did not have the AirPort Extreme Card wireless option on mine but the bracket was still located on the board) needed to be removed on my Apple iMac G5 because the cable went through the bracket and was preventing me from removing the motherboard.

I hope that helps with the finer points in this operation. If I forgot anything, be sure to point that out here.

Good luck to all that take on the Apple iMac capacitor repair challenge. Take your time, and remember it's not the IMF, (Impossible Mission Force).

 

 Vincent said... At Friday, November 7, 2008 9:47:00 AM PST

I actually have several iMac G5's in various sizes with bad capacitors. Two colleagues of mine are ... discussing ... whether one type of electrolytic capacitors is appropriate. One of them bought 100 capacitors either within or surpassing specifications. They're apparently rated for "general purpose" and cost around 20 cents per capacitor. The other colleague says they're not appropriate on the iMac G5, even if the uF and voltages are appropriate. I need to find out where these general purpose capacitors were purchases, but I'd love to get some feedback on whether those repair efforts will be wasted or not.

Thanks for reading!

 

 Jim Warholic said... At Friday, November 7, 2008 2:51:00 PM PST

There are numerous specifications and factors to consider when selecting replacement capacitors besides the voltage and microfarad ratings. For example, many general purpose capacitors are too low a temperature rating, and will likely have early failures when stressed.

Other considerations are the ESR, or equivalent series resistance measurements.

"The ESR rating of a capacitor is a rating of quality. A theoretically perfect capacitor would be loss less and have an ESR of zero. It would have no in-phase AC resistance. We live in the real world and all capacitors have some amount of ESR. To understand why let us review what a capacitor is and what they are made of and how we rate them." See: Capacitors and ESR

"Some of the advantages of low ESR aluminum electrolytic capacitors over standard electrolytics are their extended life (over 5,000 hours); higher ripple current ratings (compared to standard electrolytics); a large variety of case sizes and load-life ratings are available; larger capacitance values and standardized packages"

"The most outstanding differences are the load-life, impedances (Z), and ESRs at 100 kHz. These differences are why low ESR and low impedance capacitors are used extensively in switching power supplies to maintain the performance of the power supplies. Capacitors with too high an ESR will self-heat too much and not regulate the current properly. Obviously the self-heating will also reduce the operating life of the capacitors, and the switching power supply performance and life will be reduced accordingly. Additionally, low impedance capacitors have higher ripple current ratings than standard capacitors, thus reducing the number of capacitors needed and helping reduce the size of the switchers. See: Low ESR Capacitors: Fact or Fiction

The lower ESR capacitors are typically used in applications such as power supplies and power-smoothing circuits for motherboards, gaming consoles, car navigation systems, LCDs and plasma TVs, and motherboard CPU backup circuits. See: Aluminum capacitors offer low ESR

In my opinion, if you are going to spend the time to do the motherboard repair, I would say it is wise to spend the extra money on better capacitors, with higher temperature and low ESR specifications in the first place, than to waste having to do the repair twice.

Consider also, the extra heat that is required to melt the solder and remove and install the new capacitors in the first place. With general purpose capacitors ratings mediocre for a motherboard circuit, you would likely damage them when they are being installed.

Hope that helps.

Good luck.

Jim

 

 Kurtman said... At Monday, November 10, 2008 7:26:00 PM PST

Hi Jim,

First off, great blog! I'm an electronics technician by trade and your information was a great jumping off point for equipment I've not worked on yet. I ordered my caps from DigiKey.com - actually got the Nichicon brand (trusted that new ones would not have the same issues). I made a mistake and ordered ones that were physically 5mm larger than the originals, but was still able to replace all but a few caps, and definitely all of the swollen / leaking ones. BTW, I used a soldering station with adjustable temperature and had to max out the temp in order to melt the lead-free solder on the logic board. I was running over 800F. (Had to wear sunscreen....)

I discovered something MOST DISAPPOINTING while performing the repair, and I want everyone to know about it. I had to "work at it" to remove the solder from MOST of the existing caps HOWEVER, for a few of the caps, the solder melted VERY EASILY - just like normal 60/40 leaded solder. There was also evidence of solder flux spill around those caps, and the easiest giveaway: the solder was balled around the leads - just like it does when you hand solder and leave a lot of solder on the lead. There is NO DOUBT in my mind that I am NOT the first person to have replaced caps on this iMac - this iMac that was sold to me as a NEW product!! Needless to say I'm a little ticked.

My real issue.... the display is still fuzzy and the machine will not boot up. I seem to recall a response from an Apple tech that said there may be some damage to the display driver due to the cap problem. Do you have any further reports of this symptom as well? Do you know of any recourse I have to replace the display driver IC?

Thanks to everyone for your comments!

Kurtman

 

 Jim Warholic said... At Monday, November 10, 2008 9:45:00 PM PST

Hello Kurtman,

That's an incredible story. I'm most curious as to where you got the iMac in the first place.

Yes, I know what it feels like to have to work really hard to get the solder to melt on all the capacitors on this iMac motherboard. It is good to know that I was not the only one that had to wrestle with the melting of the solder. So, I can understand your surprise when you went to remove some of those capacitors and found out that they had already been replaced once before.

One of the aspects of this repair is the great difficulty of making sure all the capacitors are soldered solidly on the motherboard after the repair. Maybe there are cold solder joints on some of those capacitors that have been replaced once before. While it might look like the capacitors are soldered through and through, I believe it is very easy to overlook a cold solder joint because of the difficulty in melting the surrounding solder on the solder pad itself and the through hole.

I would double check all solder joints at the legs of all the capacitors, especially the ones that you suspect were replaced before. I would try to rock the capacitors back and forth and pay particular close attention to any feeling of looseness of the cap legs in the holes.

As far as your display driver IC, I have looked for a schematic for this motherboard, but I have not been able to find one. If anyone knows where one can be downloaded online, that would be great. Leave a note here.

Good luck

Jim

 

 Z said... At Monday, November 17, 2008 8:18:00 AM PST

Hi Jim,
Nice info. I used this as a starting place when fixing the bulging caps on the neighbor kid's G5.

I have done this before on a PC motherboard, and it is quite a thrash (and risky to the board) to get enough solder out of the lead holes to insert the new caps all the way. Especially if the holes don't have "thermals". It's pretty easy to cook the board, even with the "solder sucker" that I use. Drilling out the holes risks removing the barrel plating and killing the whole thing IMHO.

I took the coward's way out. I ordered $10US worth of 6.3V 3300uF 105C (high temp) caps from Mouser, and sent the board and parts to my board assembly shop (where they build our PCI boards). They charged me $20US and did a beautiful job.

Caps of the same height were unavailable so I had to go with 20mm parts. I insulated the tops with electrical tape to make sure their cases couldn't contact the metal bits on the iMac.

Once we got it all back together it worked just fine. So far.

Thanks for the great help,
Z.

 

 Jim Warholic said... At Monday, November 17, 2008 7:22:00 PM PST

Hello Z and Hello Anonymous,

Just a couple of points here. I know that some folks are installing whatever capacitors they can get a hold of. Be careful what you place into your G5. Apple's engineers had a reason to install certain rated capacitors. As I have mentioned in the past comments, going excessively higher, or lower on the microfarad ratings could be detrimental to the proper operation of the iMac.

I placed a special order with a manufacturer of caps for the exact capacitor casing size, low ESR, high temperature and high performance rated caps. They will be arriving in a few weeks. I'll be putting together capacitor kits for sale. Check back at this blog posting for an update.

 

 Z said... At Tuesday, November 18, 2008 5:44:00 PM PST

Jim,

You make a good point. I'm not too worried about the exact capacitance of the replacements, as long as they are >= the originals, with a >= voltage rating. They are just bulk filter caps for switching supplies, after all. _But_ the low ESR part of the spec is a different deal, since we're talking about relatively high-frequency supplies.

In my quick search for high-temp caps, I completely missed the ultra low impedance aspect. I should know better, but the EE degree is close to 40 years ago now. And I'm getting to the point where I could hide my own Easter eggs.

Weak rationalization: the parts that my vendor stocks that meet the specs are the same manufacturer and series that had the problem originally - Nichicon HN(M). I imagine they have corrected the problem, but still...

The repaired G5 seems totally stable now. We'll see how it holds up over time.

Folks, watch this space for Jim's replacement cap kits.

Jim, thanks for doing this. And for taking me to school.

Z.

 

 MacDaddy said... At Wednesday, December 3, 2008 8:27:00 AM PST

Z - Any chance you could share the name of that board shop? I assume they are in the Valley.

 

 MacDaddy said... At Wednesday, December 3, 2008 11:07:00 AM PST

I just cracked mine open. This is the replacement motherboard that Apple put in under warranty in Nov of 2005.
An Apple tech told me the K caps are the good ones, and I was surprised to see a few X caps on my "new" board which had bulging tops.

Two things. for those of you doing this yourself, don't forget you need a new application of thermal grease for a good seal between the CPU chip and the aluminmum panel that acts as a heat sink.

Second, I had some charring and some smoke residue on the case when I removed the board. I am suspecting that it got so hot in there that it cooked another IC on the board, so I am now skeptical that the cap replacement will solve the problem.

 

 MacDaddy said... At Wednesday, December 3, 2008 11:28:00 AM PST

A little story of my Saga with Apple
(or is anyone that purchased one of these boat anchors interested in a friendly class-action law suit???)

As I mentioned in my last post, I received a replacement board with a mix of X and K capacitors. The Apple tech at my local shop said the X caps are the bad ones, and sure enough, they were bloated on my board.

After reading some of the posts here and learning that I had a serial number in the range of the Apple repair extension program (so I actually paid for Applecare and didn't need to), I decided to contact Apple and plead my case.

The first person I got on the line seemed to be sympathetic enough to my case that he got an Apple Product specialist on the line and handed me off. Said he thought the fact that they replaced the first board with a board with a mix of known good and bad caps seemed like a good reason for an exception.

The product specialist on the line seemed to concur, but had to bring it to his supervisor for approval, where I got shot down.

At this point, the option presented to me by Apple (and my tech that I originally went to see) was $1000 to repair or $1200+ to by a new machine.

Now why on earth would I want to spend that kind of money on a product that is so unreliable from a company that seems just as unreliable? I am happy to pay a premium price for a premium product but I expect good reliability and premium service.

Additionally, in my travels to a few repair shops, I was shown shelves full of bad Imac G5's.

Somewhere on the net I read that about 20% of these machines have failed. I wonder how many of those have failed twice! Or caused a fire!

So is anyone out there interested in joining in on a class-action law suit? Even if Apple sold 100,000 of these things, that means there are 20,000 people out there with a case - that might get Apple's attention and maybe we'd all get what we paid a premium for - a machine that works.

Oh, and did I mention that when I cracked the case there were smoke stains and the case was charred. I wonder how many of these overheating units actually started fires.

My two cents - but if there's interest, I know some good attorneys.

 

 dweeb626 said... At Wednesday, December 3, 2008 3:27:00 PM PST

Just wanted to thank you Jim for creating this "how to" document.

I read it start to finish a couple of times. Then I practiced on a really old logic board. Then gave it a go.

I have successfully revived an iMac G5 (no iSight, no ambient light) logic board by replacing 5 visibly blown capacitors. Your directions and pics were fabulous. Of course it was out of warranty and for about 30 bucks I now have a working machine.

You rock!!

 

 Anonymous said... At Saturday, December 6, 2008 8:58:00 AM PST

I've just read your "how to" and I actaully have an Imac G5 experiencing problems that seem to be the same you told about concerning capacitor.

Indeed capacitors looks like normal so it is not clear to me which are needed to be replaced. Have I to replace them all?

Thanks

Andrea

 

 Jim Warholic said... At Saturday, December 6, 2008 12:39:00 PM PST

You might also be affected by the Apple iMac G5 power supply problem. Depending on the model of the power supply, and particularly which size iMac G5 (20 inch or 17 inch models) it appears that the power supplies have an overheating problem. Read more about the Apple iMac G5 Power Supplies and the repairs that can be made there.

Jim

 

 hdsc@earthlink.net said... At Friday, December 12, 2008 1:10:00 PM PST

Great site and info Jim. My g5 imac 17" 1.9ghz has a mixedup display, The cursor for instance has pixels missing that are clustered on a different segment of the screen. do you have any info on this problem or is it power supply related. The unit was under extended warranty until just before the problem, of course. hdsc@earthlink.net Thank Henry

 

 Saj said... At Friday, December 12, 2008 3:08:00 PM PST

hi,

firstly, a great article jim, good to see someone take matters into their own hands and deal with it!

i have a 17" 2nd gen (ambi light sensor) 1.9ghz cpu.

the first fault it developed was freezing but this was cured by a reboot. from there onwards it totally stopped outputting video.

on boot up, you can hear the chime, super drive spinning as it would normally but i cant see anything on the screen so unsure if it actually loads the os.

any suggestions?

i have removed the logic board and cannot see any faults with the caps, they are all the K caps.

jim, do you think it would be a good idea to change them anyway and hope that fixes it or would i just be wasting my time?

any help will be appreciated.

thanks in advance.

saj

 

 Jim Warholic said... At Friday, December 12, 2008 4:34:00 PM PST

Hello Saj,

There are several possibilities I can think of. First off, it could be a power supply problem. See the posting on iMac power supplies for more information in the G5 power supply category.

Another possibility; it could be something with the motherboard video electronics circuit. Or, it still could be bad capacitors on the motherboard too even though the caps might not look bad visually.

You might try installing an external monitor using the small special VGA Apple adapter plug on the back of the iMac to see if the OS is booting up. An external monitor, without screen spanning software installed for extended desktop mode, will display the same content as the main monitor.

Hope that helps you.

Good luck,

Jim Warholic

 

 dreamboatannie said... At Sunday, December 21, 2008 7:51:00 AM PST

Thanks Jim for a helpful article. I was about to put the second power supply in less than 2 years in my iMac G5 when I came across this article. I followed the link to the extended repair site, and it looks like I missed the opportunity by a matter of days :( December 15 was the end of the program if the message displayed on the page is correct. My iMac is indeed one of the ones affected. It looks like I am stuck fixing it myself again. Do you think replacing the entire motherboard is an option? I don't have soldering equipment. Maybe buying a soldering tool is cheaper than buying a motherboard. I am actually not pressed to fix the computer immediately as I have a car that won't start right now, and I have a laptop and a nice PC that I built myself, plus a spare box (also built by me), so not lacking in working computers! Thanks again for a very informative article. Regards, Anne

 

 Anonymous said... At Sunday, January 4, 2009 7:30:00 PM PST

Just found this site tonight. I was having problems with my four year old G5 for several weeks. Bought in Feb 2005. Has a serial number in the group of bad computers. Never heard or knew about this problem. Was not notified. We opened the back and see several bad capacitors. This just enrages me. I already bought a new computer two days ago when the G5 finally stopped working. But I feel cheated because I paid for something that should have lasted much longer. I was not ready to buy a new computer. I would like to be a part of a class action lawsuit. If anyone has any other ideas of getting Apple to take responsibility for not doing a recall on these computers so that we could know there was a problem. I have lived at the same address and a recall with notification would have been very helpful. I would like to pursue this, but don't know what could be done.

 

 Anonymous said... At Thursday, January 8, 2009 10:59:00 AM PST

I bought non working 1st gen with imac G5 1.6ghz ppc.. i thought that it would be bad caps because it was not starting.. seller said it would start now and then but i couldn't get it post.. i bought another bad logic board with 1.8ghz ppc.. it posted but there were video problems.. i measured all caps with ESRmeter and they were ok(better nichicon caps with K mark) then i thought i'd check psu but it was ok..

i then checked what kind of heatsink is in imac and realised that it has no pressure contact on GPU.. i made this..

http://xs.to/xs.php?h=xs434&d=08013&f=img_4543796.jpg

cutted the cooler(marked with red) and took like 1.5millimeters off those "feets" on GPU side.. then i put arctic silver on GPU and VOILA no video problems.. only thing is that my CPU goes like 65 celsius now so it's got bit higher because there is not enough cooling area. i thought i would put somekind of heatpipe on CPU.

my two cents :)

 

 Anonymous said... At Friday, January 9, 2009 7:02:00 AM PST

I have to detail my upper post a bit..

logic board did not post all the time.. especially after there were video problems.. so GPU heated alot and it got of it's solder "balls" whitch are under that circuit.

check out xbox 360 rrod from google.. it has same symptons. too much heat and then loosen from it's solders.. xbox has these problems with both.. CPU and GPU because there's not much pressure eith cooler's.. imac got good contact with CPU so that's not the problem.. only GPU.

I think caps are not the problem in these european imac g5's.. SPU's are made little different than in USA(230volt's in EU)

there's lot problem's with logic board's in EU but the problem is this what i said. of course caps too but not so much

in USA you have weaker PSU's that blow logic board caps.

 

 Jim Warholic said... At Friday, January 9, 2009 7:55:00 AM PST

Hello Anonymous,

Well, I'm still not sure exactly what you did with that CPU adapter above. The back of the motherboard with the CPU fits perfect up against the heatsink. Silver thermal paste, in a paper thin application, makes for a good heat transfer. But back to the capacitors for a moment. You mentioned when using the ESR meter to check the caps, they check OK. Keep in mind, other components in the circuit can affect the readings. Other good capacitors in parallel could make a bad capacitor check good using an ESR meter. Also, I'm not sure I agree with your assessment that the EU has stronger PSUs than in the USA. What are you basing that on?

My two cents worth.

Best regards,

Jim

 

 LIAM! said... At Tuesday, February 3, 2009 5:16:00 PM PST

first jim,
thank you so much for this tome of great info! can't stress that enough!

ok, i have a 2nd gen imac G5 which has had the power supply replaced last summer after intermitent power failures under extended warrenty.

when i brought it in they did not explain one thing to me about the actual cause nor solution, they just told me essentially, "it's fixed now". thanks genious.

as of last week the computer has started to die on me yet again, right in time for the extention on replacement to expire!

I am now going to crack the puppy open and give it a good look and hopefully with my limited soldering knowledge i can remedy this issue.

BUT, I was also never made aware of this problem in the first place, nor informed that the extention of replacement was to expire or it could even happen again. I expect a little better treatment as a consumer and as stated previously when you pay for a premium product, you expect a little more!

keep you updated and thanks again jim!!!

LIAM! Malone

 

 Ingo said... At Friday, February 6, 2009 3:46:00 PM PST

SUCCESS!!!

I just successfully repaired an iMac G5 using a capacitor kit by Jim. (Thanks Jim for the infos on this site and for providing the "hardware".)

Additional to the information by Jim I'd like to share my experiences regarding:
- Taking the iMac apart
- Helpful Youtube videos on soldering
- Removing the old capacitors

TAKING THE IMAC APART:
- I downloaded the do-it-yourself manuals for replacement of hard-disk, optical drive, fans and power supply from the Apple website (browse http://support.apple.com/manuals/#imac).

Most parts are quite easy to remove. You'll need Philips No.1 and 2 and Torx No.10 screwdrivers.

- I printed out the interesting pages of the downloaded PDFs and adhered the removed screws to them using a scotch tape, so they could not get lost or mixed up.
- The power supply was a bit tricky, and there's only a PDF referring to the 17 inch model. I found out that the screw that is also used for loosening the cover of the iMac only touches the power supply and doesn't actually screw into it, so if you loosen the remaining screws you should be able to lift the motherboard side of the power supply and take it out (I left it in first and discovered how to remove it only before putting the motherboard back in place).
- When all the parts are taken out, there are 8 Torx No.10 screws and one Philips screw (left bottom corner) to be removed and then the MoB is free. No, not yet, make sure that all plugs are removed (especially the ones left of the power supply, and the AirPort antenna cable).
- Pay attention to the funnel under the left hand lower corner of the MoB that confines the sleep light to the sleep light spot on the front side of the computer.

Helpful Youtube videos on soldering (for newbies like me):
- Youtube movie on removing caps (the one linked by Jim above): http://www.youtube.com/watch?v=on_2CP52cW4
- Youtube movie on soldering techniques: http://www.youtube.com/watch?v=I_NU2ruzyc4
- maybe also helpful for theoretical background (and for some exploding capacitors in moving picture) Youtube movie: http://www.youtube.com/watch?v=YCSNWi3UHf4

Removing the old capacitors:
Problem: sometimes the old capacitors' leads seem to fit in the holes only just, so sometimes I had the impression they got stuck even if the solder was heated enough.

This is how I removed the caps after gaining experience with the first ones:
- I added a bit of fresh solder to form a better heat bridge between the soldering iron and the capacitor's leads. By doing this I could skip scratching or grinding off the polymer covering the solder joints, it just melted (or burned) away...
- Start tilting the cap only slightly. Then change over to the other lead.
- Find out which lead comes off harder.
- Remove the leg that comes off harder first.
- I experienced the most time-consuming problems getting out the old solder completely from the holes. I did not have a drill little enough and would have hesitated to apply it anyway, so eventually I had good results by absorbing the leftover old solder with and desoldering braid/wick. Most of the time, if at all, only a very thin cover of solder left above the hole. This I pierced with a needle and some more heat from the soldering iron. It went quite well in the end that way.

So, in short, my best way to getting off the caps was:
1) Add some fresh solder to from a heat bridge (like in the 2nd above mentioned youtube video).
2) Tilt the two leads one by one only a little and find out which one is harder to get off. First remove this one.
3) Desolder with desoldering wick and pierce the hole through with a needle while heating with the soldering iron.

I did not experience any ripped-off capacitor legs. Maybe it was the technique I applied or mere luck. Probably the latter.

Soldering the new capacitors in was not a problem.

I enjoy my new computer now for a couple of weeks running Mac OS 10.5.6, and the temperature monitor reports nothing extraordinary, the picture is fine and I think I had one crash during that time after loading it with sh.t-loads of data...

Good luck to anyone who'll try it too!
Ingo

 

 Gordon said... At Friday, February 13, 2009 7:19:00 AM PST

Thank you Jim for this v. informative help. My first gen. iMac G5 was repaired a few times under warranty (power supply, logic board and finally hard drive) but now it has died. Following an Apple diagnostic to reset the SMU (no go)with the back cover off, the flowchart indicates ¨replace the logic board¨.

Apple Dicussions brought me here. Trouble is, after carefully looking at the 25 capacitors on the board, I cannot detect any which are swollen or bulging. (As some were before a prior Apple repair)

Question 1: Could something other than defective capacitors be the problem? Or is this 99% of all troubles? Suggestions for a deeper diagnosis?

Question 2: Do you replace all 25 capacitors? Most seem to be 6.3 volt & 1800mfd, but I noticed at least one at 18 volt & 1000mfd if memory serves.

Thank you for these excellent helps and user comments.

AlexG

 

 Jim Warholic said... At Friday, February 13, 2009 4:41:00 PM PST

Hi Gordon,

Your story with Apple iMac G5 repairs has a definite pattern to it. Many other Apple iMac owners are in the same boat as you.

Answer 1: There is a possibility, even though the Apple diagnostic flow chart might point to the iMac motherboard at being at fault, that it could actually be the power supply problem. See my link near the top of this article about the do it yourself, Apple iMac G5 power supply repair.

Answer 2: I highly recommend that you replace all of both types of main motherboard capacitors (6.3 volt set and 16 volt set). I am selling high quality, low ESR, low impedance rated, motherboard grade, and switching power supply grade, complete capacitor sets. For information about the caps, see in the article above. Feel free to send me an email for more detailed information if you wish.

If you have more detailed questions that you would like answered, or would like to provide contact information for an email update, and/or to send pictures of your Apple computer, feel free to send me an email either using a formmail, my email address at the top for picture attachments, or go to my contact page link above.

 

 Martin Whitecotton said... At Tuesday, February 17, 2009 7:26:00 PM PST

Worked great. Bought the caps from Jim. New paste on the CPU. 8 hours. But worth it - I'm getting good readings on it so far. Temps on the CPU around 150 f.
The caps popped right out. I used some sewing pins and heated up old solder to clean the holes for the new caps. FYI.

 

 Anonymous said... At Thursday, February 19, 2009 9:48:00 PM PST

I purchased Jim's kit and used it to successfully revive my 1.6Ghz iMac G5.

Taking the iMac apart was easy once I figured out that I didn't have to remove the lower fan. I followed the Apple guide but was unable to remove the fan and ended up slightly bending the band that holds the fan assembly. The hard drive, fan shield, optical drive, inverter, and airport card were easy. I was also curious how the logic board would come out since I couldn't find anything online about it but it was easy.

Once the logic board was out I found it very easy to remove the capacitors. I just head one lead at a time and put pressure on the cap to pop out that lead. I probably had all of the caps out in 5 minutes. Getting the holes cleaned out was another story. Using pins from a sewing kit and the iron I managed to push out the solder. I also used desoldering braid to soak up the solder. All in all I found the soldering challenging but it did work. Oh I forgot to mention that I used a dremel tool to go over the solder joints after I removed the capacitors. I'm not sure if that help.

Putting the system back together went really well. I used the ArticSilver mentioned above and referenced some pictures I took as I took as I disconnect the various connectors.

If anyone is interested I posted pictures of the whole procedure here: http://www.rockrapidswx.com/imacg5_fix/

Jim's kit worked great and I'm going to order another one if they are still available to fix my other broken iMac.

Chris R..

 

 Anonymous said... At Sunday, February 22, 2009 10:48:00 AM PST

Hello from France.

Thanks a lot for all the information.
My fist generation iMac G5 has a problem with the motherboard ... and is out of warranty (bought it in May 2005)

I called the Apple Hotline, and they will accept it, to repair it for free... (otherwise it would have cost me 794 Euros or 1018 Dollars)

So I'm really happy..

 

 shadoworks said... At Monday, March 9, 2009 1:32:00 AM PDT

Hello Jim

I purchased your capacitor kit and attempted to repair my IMac G5 1.8GHz Version 1 (2004), which had already had two replacement power supplies fitted by me. It had five blown capacitors but I had all 25 replaced. I am not a techy person so had to find someone to do the soldering for me- which was not easy on this Greek island dominated by PCs. Anyway I found him (there is only one) and he did a good job. My only problem was that in taking out the logicboard I seemed to have damaged the connection to the Hard Disk Temperature sensor on the side of the Hard Disk, so I bought a replacement tiny cable for it and thought all would be fine. When I put back the logicboard and tried to start up it took several tries before it worked - so I quickly did a Service Diagnostic Test and it failed on Ambient Temperature Sensor Error -25128 - so I bought a complete new Hard Disk Temp Sensor and cable and fitted them- still got the same Error message even though the computer started up OK now. So I downloaded Hardware Monitor and Temperature Monitor software and neither of them can locate the Hard Disk Sensor. Do you or anyone think this is a problem? The hot season does not start here for another three months, meanwhile the Smart Hard Disk Temp is recording around 50C, but the Hard Disk Fan never moves from the minimal speed- (it is spinning). I would appreciate any advice, comments, whatever as I am still worried that all is not quite right, and don't understand how the sensors work really.

I appreciate all you have done for the Apple community through these pages Jim, you deserve a medal from Mr Jobs.

 

 Jim Warholic said... At Monday, March 9, 2009 7:34:00 AM PDT

Hello Shadoworks,

I'm not sure what will happen in the case of the hard drive temperature sensor not functioning properly. Note: My hard drive, Smart Disk, and CPU temperatures are within 7 degrees C of one another. CPU temperature is 52 degree C, Hard Drive is 51 degree C, and SMART Disk is 45 degree C.

All my fans are turning at much lower speeds (very quietly) and since I have replaced the capacitors, the temperature has always been much lower than before and the fans never sound like a vacuum cleaner anymore. I'm sure they will turn faster when the ambient temperature inside the iMac gets hotter.

Thank you for your comments Shadoworks. Maybe someone else has more insight into this temperature sensor area.

For others out there, be careful when taking things apart.

 

 Anonymous said... At Sunday, March 15, 2009 12:05:00 PM PDT

This may be a silly question, but could someone recommend, specifically, what diameter and type of solder I should use for this?

 

 Jim Warholic said... At Sunday, March 15, 2009 12:55:00 PM PDT

Hello folks,

It is not necessary to use lead-free solder when doing the repairs. You can use standard 60/40 formula, 0.032" diameter for electronics work. Even 0.062" diameter 60%-tin/40%-lead Rosin Core Solder will work just fine too. The solder diameter is not as critical as the core type. Rosin core is key to success. Do not use acid core solder or acid flux; as this will damage and corrode the mother board. Note that there are other newer types of solder that have what is known as clear flux rosin core solder and even have various formula variations of rosin types. Some say this is better than standard rosin core solder. Supposedly clear flux core solder provides better wetting action and dries smooth. Also, make sure you heat up the existing lead-free solder remaining on the pad and through holes enough to join together with the 60/40 solder; otherwise you will end up with cold solder joints between the mother board and the capacitor leads.

Any Radio Shack will have those types of solder. A small quantity of 60/40 solder will cost you in the neighborhood of 4 or 5 dollars.

 

 Rj said... At Tuesday, March 17, 2009 5:18:00 PM PDT

Greetings!

I purchased an iMac for my mother and father back in 8/2005. Thankfully I purchased AppleCare.

Interestingly we had some problems with the unit RIGHT before AppleCare expired. The tech replaced a number of things, including the logicboard, ambient light sensor and LCD panel.

I received a frantic phone call from my father stating that the iMac had a blue screen on it and appeared locked up. He reset the iMac and appeared to be functioning.

Today, I again received a call indicating problems. This time I checked out the unit myself and ran the Techtools. An open firmware indication appeared and also stated memory bus problems.

As the unit was out of warrenty, we replaced the unit with a new one.

I brought the old one home and starting to search if anyone had a simular problem. I contacted Apple, they walked me through a number of trials that didnt' work. I brought up the "Capacitor" issue with the rep and it appeared to change things abit. The rep discussed a repair program that Apple had but advised me the program ended in Dec.

I was then transferred to a tech which reviewed the history of the machine. We discussed the capacitor issue and after about an hour of so of discussions and wait times, Apple agreed to have me bring the unit into a Apple Certified repair center and if the issue is related to the capacitor problem, they would repair the unit at their cost.

I started to wonder if it was indeed a capacitor issue and when i removed the back cover, there were a number of capacitors that are bulging. (No leaking yet).

I hope this helps others that may be in the same position.

I'll let you know what happens to the unit. I may request a replacement as three times are a charm!

 

 Thomas [ jänis jvpite®ssøn ] Pichler said... At Wednesday, March 25, 2009 3:07:00 AM PDT

Dear Jim

1st of all, many thanks to all this work from the Alps in the south of Bavaria, near Munich, Germany, helping other G5-"victims" and create this very helpful Website by spending so much time on this issue, i guess.

It seems, this happens to my iMac G5 right now.
My turning point is, I never ever have any experierence with electricity nor soldering, an things like that. Any suggetions? Do you think, a PC-guy can repair this as well?

Sorry 4 my bad english

greets your

_________________________________________
[ jänis jvpite®ssøn ]

 

 Jim Warholic said... At Wednesday, March 25, 2009 7:46:00 AM PDT

For those that need help on repairing their motherboards, and need help with soldering, I suggest doing the following.

I would suggest ordering the capacitors from my ecommerce store, and also print out this repair procedure. You can click on the PDF link on the right, and save it on a disk or you can click the print button. The pdf file might be a better way to go.

Once you have the printout in hand, take it to a local PC repair place, and get a quote for the motherboard repair.

You could either take the whole computer in, or you could remove the mother board from the chassis.

If you have a friend or family member that knows how to solder, they could help you out too. Treat the friend to a nice dinner afterwards, or buy them a new iPod shuffle for their help.

Hope that gives you some ideas on getting the iMac G5 fixed.

 

 Anonymous said... At Wednesday, March 25, 2009 9:43:00 PM PDT

Hey guys. I replaced every capacitor using Jim's kit, and when I put it back together and turned it on, the machine booted (it didn't boot before!) but I have no video whatsoever. The screen is completely black.

Before the repair, I did have video -- just a grey screen that it sat on. But now, no video.

I can verify that the machine boots into the OS, because if I plug in a network cable, it obtains an IP address on my network.

Any suggestions as to why I might have no video now, or how I could try and fix it?

 

 Jim Warholic said... At Wednesday, March 25, 2009 10:49:00 PM PDT

You might double check your power supply. Sometimes both the mother board and the power supply have faulty capacitors. I have heard from a few folks, and have confirmed that they had to replace both the capacitors on their G5 motherboards, and the capacitors on their power supply units.

Also, double check your soldering, and make sure there are no cold solder joints. This is super critical to make sure you have good solder joints. It is very easy to think that you have soldered it to the board, because the solder will melt much faster to the capacitor leg than it will melt and attach itself to the motherboard pad and circuit board through hole. This is because, no matter if you use rosin core 60/40 tin/lead alloy solder, instead of lead free solder for the capacitor replacements, the solder still has to melt to the motherboard lead-free solder remaining on the pads and in the multilayer circuit board through holes. So, make sure you are using a good soldering iron for the job. Trust me on this one.

Check out my article on the DIY repair for the PSUs. In my article titled: Apple iMac G5 Power Supply Issues and DIY Apple Repairs, I dive inside the power supplies with more detailed pictures and repair procedures. The iMac power supply caps are actually easier to unsolder and solder than on the Apple MOBs.

If you read the original Apple extended repair service announcement, you will see in that Apple repair service agreement, it was covering both the motherboard video problems and the power supply problems with the three year repair service extension program. So, it would not be unusual to have both the MOB and the PSU go out. If the MOB caps are faulty for an extended period of time, this in fact weakens the PSU caps. If the PSU caps are bad for an extended period of time, this has a cascading affect on the capacitors on the mother board. The capacitors end up all having to work much too hard to filter the ripple current that should have been filtered by the power supply. This in turn causes the capacitors to super heat, and go into thermal meltdown failure mode.

There does seem to be a slight pattern developing. Some of the iMac 17 inch models tend to have power supply problems showing up, and then the motherboard capacitors go out. The 20 inch iMac models tend to have MOB capacitors fail first and then the PSUs go out. However, this is not always the case, in as much as there seems to be other factors involved in the failures, such as the year built, and what batch of bad Rubycon capacitors were used in the motherboards, and the batch of bad Ltec capacitors that were used in the power supplies.

The differences between the engineering design of the Apple iMac G5 17 inch and 20 inch models for internal heat removal are probably a significant factor between each of the computer iMac failures. The 17 inch is actually much more compact, and probably generates different internal heat buildup, (hot spots) as compared to the 20 inch units with wider landscapes and more internal surface areas and different air flow characteristics.

As far as the capacitors for the Apple iMac G5 power supplies are concerned, I am expecting extra long life, low esr, 105 degree C capacitors for the PSUs shortly. I will have these in kit form for each particular power supply. Send me an email if you want to get on the PSU capacitor notification list.

So, it is a good idea to take a look inside your power supplies.

Note, I have the iMac 20 inch model that I needed the caps on the mother board only. On the other hand, my iMac 17 inch test unit, I definitely needed capacitors inside the power supply.

Hope that helps everyone.

Best regards,

Jim

PS You can use my form mail or the email contact link if you wish.

 

 Brian said... At Sunday, March 29, 2009 10:01:00 PM PDT

Jim,

I went back and touched up all my joints with the soldering iron, just to make sure I didn't have any cold joints. Then I carefully put everything back together again, and this time before turning it on (but after plugging in the power cord) I hit the SMU reset button. I turned it on, crossed my fingers, and SUCCESS!

So, if anybody else ends up with the same issue I had (go through capacitor replacement, system seems to boot fine but no video), I recommend doing an SMU reset.

 

 Anonymous said... At Thursday, April 16, 2009 6:01:00 PM PDT

You mention "The various models associated with this particular DIY repair document are for Apple: iMac G5 (20-Inch), iMac G5 (20-Inch iSight), iMac G5 (17-Inch), iMac G5 (17-Inch iSight), iMac G5 ALS (17-Inch), and iMac G5 ALS (20-Inch) consumer, university, and student models."

However, the take-a-part for the iMac G5 insight models is entirely different (from the front instead of the back) and I haven't found anywhere how to do it. So, working on the power supply is a moot point.

 

 stevo said... At Friday, April 17, 2009 5:04:00 PM PDT

I have a 17" iMac G5 ALS. Back in December my power supply started acting up (computer would just turn off randomly). So I replaced the power supply and everything was fine. Then last weekend I got a kernel panic and when I rebooted I got the spinning beach ball and none of the applications would work. I was able to boot in Safe Boot mode. Looking the console log I was getting an ASIC hang message and it appeared the Radeon 9600 drivers weren't running properly. I had seen this site back in December and got to wondering if it was some of those bulging caps. I took it to the Apple store and the genius looked inside and confirmed that yes, the caps were bad and I needed a new logic board. Various things would stop working right as the caps failed. So I ordered the 29 cap kit from here which promptly arrived a few days later. I took out the logic board and replaced the 29 caps, put it all back together, turned it on all all works normally! Thanks for the tips, and for the comments from other who have tried this and had success- that was encouraging.

 

 kernel_panic said... At Tuesday, April 21, 2009 7:11:00 AM PDT

Hi Jim

I have just successfully replaced capacitors on my imac G5 1.6 machine, it went well. Several of the legs broke of which was daunting. I was able to successfully drill the holes out. I no longer have the spinning disk or the hoover like fan syndrome. How ever I was still experiencing random lock ups. I downloaded smart utility to check hard drive and unfortunately it is failing. I have also noticed cpu temps are now lower, previously idle temp was @ 60+ degrees celsius and with a load it was as high as 76 degrees, post repair and idle temps are down as low as 56 degrees and load temps seem to max out at @ 71 degrees. So I am very happy with how it went. I did go to the local tv technician (retired) but he didnt have an iron that could work with the lead free solder so I purchased a 60 watt soldering station and did it myself.
Your guide was extremely helpfully and very easy to follow, and the comments from other users who had successfully done the mod provided me with the confidence to give it a go.

regards

Scott

 

 Anonymous said... At Thursday, April 23, 2009 12:00:00 AM PDT

Jim, (or anyone else that might be able to help)
I recently recapped 2 Imac G5s. One a 17", one a 20". The 17 went smoothly enough and is currently working. On the 20" I replaced the 1000uf 16v caps that were bursting and recapped the PSU. It came back to life, but still had some issues. I proceeded to replace the 1800uf 6.3v caps. The unit now shows diag light 1 steady. When I press the internal power button, the second light comes on, the HD just starts to spin and the power light comes on, but then everything goes off and the 4th LED lights up red (which would indicate and overheating condition). I have gone over everything I can think of time and time again. anyone have any ideas what might cause this? A thermal diode or something of that nature? I'm frustrated with it and could use some ideas if you have any...thanks.

 

 Jim Warholic said... At Thursday, April 23, 2009 1:59:00 AM PDT

It is possible that something else has gone out in the power supply other than the capacitors.

I do have a few questions:

Did you replace all the capacitors of the 1000uF 16V and 1800uF 6.3V capacitors, or just the ones that looked bad? Remember, it is always a good idea to replace both groups of caps completely. Don't just think that the ones that are bulging are the only bad ones on the MOB. Capacitors can go bad with no outward physical signs of a problem, especially in light of the problem with these bad Rubycon capacitors used on the MOB.

Did you use low ESR capacitors on the power supply recapping?

Is your power supply getting hot to the touch? If so, it is likely that something else is bad in the PSU.

Other items to consider also:

Reset the System Management Unit (SMU) by pressing the SMU button. See the Apple iMac G5 Troubleshooting document for more support information.

"If you're using an iMac G5 (Ambient Light Sensor) computer, your SMU was already reset when you unplugged and replugged the computer. You won't see an SMU reset button to press, and that's OK, as this action has already been done.

If you aren't sure which iMac G5 model you have, click here for help."

Take it from experience here, if something is intermittent on the power supply, or the power supply is faulty with one of the voltages having too much ripple, the indicator LEDs may not display the proper indicators of the actual problem.

Note: I am waiting for two key capacitors for the power supply capacitor kits that I will be selling. I expect these in very soon.

Feel free send me an email to be notified when I have these power supply capacitor kits available for sale.

Jim

 

 Anonymous said... At Thursday, April 23, 2009 6:58:00 AM PDT

Jim,
Thanks for your reply. I response to your questions, I have a first gen 20" (no ALS). I replaced ALL of the caps with Rubycon MCZs (K vent), whether they looked bad or not. The PSU had already been recapped and was running the Imac before that, and I have already tested with another PSU (known good) with the same result. I have checked and rechecked everything with a magnifier to make sure there are no shorts or solder splashes. I'm about at my wit's end with this one.

 

 Jim Warholic said... At Thursday, April 23, 2009 7:36:00 AM PDT

Well, you have one of several problems. Either the Rubycon MCZ (K vent) caps that you installed are old and possibly bad themselves, or you have cold solder joints in the through holes, or you over heated the caps when you installed them (potentially damaging them when they were installed), or something else on the motherboard is bad.

There are just too many variables in the mix.

As I said in the article, I am not sure I trust the Rubycon brand, after all it was the Rubycon capacitors that were installed in the first place on all of these iMac G5 motherboards. That is why I am not selling the Rubycon brand.

I am more than a little surprised that Apple stuck with the Rubycon brand for so long through this whole bad capacitor episode. Why on earth, with so many other capacitor manufacturers, would Apple continue to risk their brand image, by using a capacitor manufacturer that was producing capacitors that started failing months after they were installed? This is way too early for failure of capacitors to occur. I'm sorry Apple, this does not make sense in my book. Yes, I place most of the blame on Rubycon, but Apple needs to take a look at their manufacturing policies too. Reports of failures of the motherboards started occurring very early in the life of the iMac G5 computers. Folks in the Apple forums have been talking about this problem for years.

This is just my opinion.

 

 Dave Clarke said... At Friday, May 8, 2009 3:02:00 AM PDT

Hi Jim, I have a 20" ALS 2.0GHz G5. The iMac boots up just fine, but the 3rd LED never comes on and the screen stays black.

The power supply is only a couple of months old and smells fine, looks fine. It was replaced by Apple before the warranty ran out. The capacitors on the motherboard all look perfect. Happy to replace them all, think the problem is likely to be with them? Cheers Dave

 

 Jim Warholic said... At Friday, May 8, 2009 8:00:00 AM PDT

Hello Dave,

Here is some information that someone wrote to me concerning the LED indicators as they relate to the power supply repairs. However, we can learn some things from these LEDs as it relates to the MOB too. Also keep in mind, that the MOB and the PSU caps tend to work in conjunction with one another for proper filtering action. One other note is that the LEDs do not always explain the gospel truth. If you have flaky problems on the MOB or the PSU the LED indicators can give you a false report.

The LEDs on the mother board indicate the following. #1 LED shows it is detecting trickle voltage from the p/s (if you don't see this LED, with the machine off but plugged in, it is not a good candidate for PSU repairs unless fuse is blown on the PSU), the PSU should be replaced in this case; #2 LED comes on when the m/b sees all correct powers (voltages); #3 LED shows the computer and LCD talking OK; #4 LED is strictly an overheat indicator.

It is possible that something else is wrong with the PSU or the MOB.

I would also be curious what happens when you plug in an external monitor.

Jim

 

 Anonymous said... At Sunday, May 10, 2009 6:06:00 PM PDT

Here's post from a newly assembled iMac G5 with the 29 Caps replaced!!

Thank you, THANK YOU, JIM!!!!

 

 Anonymous said... At Sunday, May 17, 2009 7:25:00 AM PDT

Hi,
Anyone here experienced a loss of color? My iMac seemed to have lost the ability to display blue. During the normal boot sequence the screen goes from white to yellow(light green depending on your eyes) instead of the normal blue. Any suggestion as to what might be wrong?

 

 Jim Walker said... At Sunday, May 17, 2009 3:25:00 PM PDT

My 17" iMac G5 ALS that died a slow death last month... I guess I was witnessing the failure of one capacitor after another. So, I purchased replacement caps from you, Jim, and just now the computer powered up with no issues.

The first problem I noticed a few months ago was the loss of my Bluetooth module - it says "not available" - and that is the only remaining issue. I suppose that the module itself was damaged when the specific caps failed. But, I really don't use Bluetooth for anything, so I consider this repair a complete success.

Thanks for providing all of the great documentation and for offering the necessary capacitors in an easy-to-order package. Counting the caps, new soldering iron, and silver thermal paste, I spent about $55 for this repair.

Thanks a lot...

 

 Anonymous said... At Tuesday, May 26, 2009 11:47:00 PM PDT

Hello from Chicago,
I purchased my 20" G5 1st gen iMac in May of 2005. I August of 2006 my display showed vertical lines, froze, overheated and wouldn't boot. Apple replaced my power supply and Logic board at no cost to me (it fell under the secret recall program!). Things have been ok until last week when all my applications began failing, then the unit wouldn't boot beyond the grey screen. I brought the unit to the Apple store today, where they told me the hard drive was failing. Luckily they were able to get the hard drive to respond after the third try, so I immediately purchased an external and sucked all my pics and music off! He offered to replace the HDD for 200 bucks, but instead I purchased one myself to save money (1TB for 88bucks!!)

Here's where I get mad! I happily removed the back panel thinking what a smart and thrifty guy I am only to find BULGING AND OOZING CAPACITORS on the new logic board!!! What a joke! The computer is only four years old! I love Mac products, but come on. What are we paying for? Sure, they can hire designers with OCD who create great packaging and software, but look what's under the hood - crap parts! Mac needs to take care of this! I am outraged!!!
Here's where i get happy! I still have the chance to be smart and thrifty with all the great info in this blog string. Will post following confrontation of the geniouses.

Many thanks,

D.

 

 Aaron said... At Wednesday, May 27, 2009 4:47:00 AM PDT

Hi Jim,
my ALS 20" iMac has similar probs to all the others here.
The thing I don't have is bulging leaking or blown caps on the logicboard or in the PSU.

The PSU has been changed over twice under the PSU exchange program, this only work for about 3months, then the mac would resume slowing down all activity (quickly), then instant sleeping, blacking out or shutting down.

I now use it for music recording, the iMac now runs poorly most times. The CPU hits 80c and fan 4400rpm then everything starts to run almost in slow motion, all apps start to run really poorly, sort of lagging. In the past it would take a little bit before the heat on the CPU and fans would go up, but it's almost instant now as soon as i start the mac, the CPU goes to around 70c and fans 3900+.

Would your Caps kit fix this?

I took the PSU to an electronics guy and he said there's no need to do anything cause even dried up faulty Caps love the heat and work better when over heating.

But it's the over heating that seems to cause the problems.
and i don't want to glue a big fan to the back of the case like some have.

 

 Jim Warholic said... At Wednesday, May 27, 2009 8:51:00 AM PDT

Hi Aaron,

Your electronics guy doesn't know what he is talking about. Capacitors do not work better when overheated. Capacitors fail faster, and are likely to vent the electrolyte from the tops or the bottom plug of the various electrolytic capacitors throughout the computer. Once the electrolyte is dried out, the capacitors will not filter the ripple voltage, will not supply the proper DC voltage to the rest of the computer, and will in themselves cause additional overheating of both the capacitors themselves and the rest of the computer because of the lack of proper filtering action.

The electrolyte from inside the capacitors can dry out the and even the capacitors can get old and not properly function. Some will not show any signs of damage on the outside, but will not work properly from the inside. The power supply and the logicboard capacitors tend to work in conjunction with one another. If the MOB capacitors are not properly filtering the voltages, then the PSU will have an early failure because of having to work much too hard to maintain the voltages. Likewise, if the PSU capacitors are not filtering the ripple voltage properly, then the MOB will have an early death.

Certainly, keeping the capacitors cool on the power supply and motherboard, as well as keeping the whole computer cooler will add to the longevity of any computer's life. If running computers hot were the way to go, there would be not need to install any fans at all.

In your particular case, your computer is overheating for some reason and shutting down. There are numerous possibilities in addition to the caps. The CPU is getting hot on your iMac. Make sure all vents are clear of any dirt and fuzz buildup. If the cooling vents are plugged on the inlets, the computer will overheat.

As far as the cap kit is concerned, I can not promise that if you replace the capacitors that do not show any visual signs of problems, that it will fix your particular problem. However, if you have tried everything else, and Apple will not fix it for you under warranty, what do you have to lose? For most folks, it is not too much to lose, but a little time, effort, and a small amount of money to try the capacitors.

Best of luck to you.

Jim

 

 Justonge said... At Wednesday, May 27, 2009 11:25:00 AM PDT

I've just completed the job and switched the G5 back - fingers heavily crossed. It's fired up and running and so far all seems to be fine. I'll leave it running for a while and check the problem doesn't reoccur once it's warmed up but i'm hopeful it'll have fixed it. Thanks for the guidance, i'm not sure i'd have attempted something like this without it.

 

 CJ said... At Friday, May 29, 2009 9:39:00 PM PDT

iMac G5 purchased June '05. It just died on me last month. even though the replacement program is over, when the store told it me was the capacitors Apple support agreed to extend the program and repair my computer for free. Super stoaked about it. I thought my computer was trashed. I decided to swap out for a larger drive while Im at it. Anyone know if its possible to upgrade the processor to the Intel, or is that part of the motherboard itself...?

 

 Anonymous said... At Friday, June 5, 2009 1:55:00 PM PDT

Was getting a grey screen only on startup, but logic board diagnostic LEDs 1-3 were green. Booting from Hardware test disc also showed no problems, but I could not access the hard drive without removing it and connecting to another computer. Installed 25 new capacitors from Jim and the machine is back to normal. Used a Weller SP40L 40W soldering iron (large chisel tip) and desoldering braid. Fancy solder sucker did not work for me ($12) Had to do minor reaming/drilling by hand (pin vise) with a tiny drill bit (set from Harbor Freight for $5) prior to soldering in new caps. THANKS JIM!!!

 

 Anonymous said... At Monday, June 8, 2009 3:37:00 PM PDT

Hi, I have a question somewhat related to these posts. I've had G5 iMacs with logic board, and PSU cap problems and have been able to fix them with the assistance of these instructions and posts. Thank you all very much!

Here's my question. I have just come into ownership of a 17" G5 iMac that is without it's hard drive. I happen to have a WD Caviar SE Serial ATA WD1600 that I would like to put in. The HD has the chassis, and the small cable at the bottom which plugs into the logic board just under the RAM. The computer has the bigger of the two cables (the one that plugs into the logic board just beside the large fan housing), but, it does not have the smaller one.

My questions are:

What is this cable called?

Does anyone know of a ready supplier (I'm in Arizona so the SW US would be nice)?

and Where the heck should I plug the cable into the computer when I get my hands on it? I don't happen to have on handy to look at.

Thanks

Mac

 

 Jim Warholic said... At Monday, June 8, 2009 5:29:00 PM PDT

The the question about upgrading to an Intel processor. The processor is integrated into the motherboard. So, there is no way to remove it from the MOB.

The question about the two plugs on the hard drives. I believe one is the data plug, and the other is the temperature sensor.

 

 Tim Kerger said... At Tuesday, June 9, 2009 11:51:00 AM PDT

Hi Jim,

Let me first start by thanking you for your excellent guide! You're helping a lot of people with it (including me).

I have a question however.
Symptoms:
iMac starts up normally, but no display. Hear the chime when startup, fans spin. Hear reading from hard drive and starts up normally (into OS X). Fans start to spin really hard after 5 minutes.

Work performed
-LED3 does not light
-Reset SMC
-Capacitors all look good, not blown or leaking (both on logic board and PSU)
-Serial number falls out of range from Apple repair program

What should I do? Replace the capacitors or is there a different defect? I'm gonna try hooking it up to a ATX power supply to check the supply.

Any thoughts? Seems to me that defective capacitors are strange, because bootup is otherwise fine....

 

 Jim Warholic said... At Tuesday, June 9, 2009 10:20:00 PM PDT

This is a particularly difficult problem area to troubleshoot, when trying to track something down that doesn't exactly conform to visual indications with the capacitors.

It could be either the PSU or the MOB. If the output from the PSU is low on one of the voltages, this could cause a no display condition, yet it sounds like it comes up properly with the software. The fact that the fans are spinning fast, sounds like it is not powering up properly.

A couple of ideas would be to try an external monitor to see if that has a display. However, given the fact the fans are running fast after five minutes, it sounds as though it still has issues of it not powering up properly or going into an overheated mode of operation.

Capacitors can dry out internally of the electrolyte, and not filter the voltages properly. This in turn can cause the iMac to run hotter than normal. If you can measure the DC voltages from the power supply to the MOB, at the main PSU/MOB plug, (see iMac G5 power supply article on repairing PSU for DC voltage measurements and pinouts) and at the same time measure the AC ripple voltage present; it can tell a lot about what is going on with the computer.

A half way decent digital voltmeter can quickly measure the ripple voltage by measuring the amount of AC voltage present on the DC voltage levels. The ripple voltage level should be in the low AC millivolts range, in my opinion. I have not actually measured it myself on any of my iMacs, but based on other PSUs that I have measured, this should be the case with the iMac too.

Some folks have replaced capacitors on the MOB that did not show any physical signs of damage for this type of iMac display problem, and the replacing of the capacitors did fix it on some iMacs and not on others. Also, if you only see one bad capacitor on the MOB, don't just replace the one capacitor and think the others are OK. These other capacitors are surely on their way out too (if not already damaged even though they show no outward signs of problems) because of increased work loads due to the other defective capacitor(s). Nothing lasts forever.

I still maintain the theory that the MOBs and the PSUs tend to work in tandem with one another. If one or the other units (MOB caps or PSU caps) is starting to have filtering problems, then the other has to work that much harder to provide the same voltage and current levels. This is why sometimes when folks are first starting to have problems, and then they try to run the iMac with a problem of shutting down repeatedly, it stresses the other components to the breaking point in a PSU or MOB and taking it beyond the simple capacitor repair state.

So, the adage here is, if you are first starting to have problems, make sure all your vents are clear, and inspect your motherboard and power supply capacitors for any signs of bulging. If you see bulging on the capacitors, replace them ASAP.

 

 Anonymous said... At Friday, June 12, 2009 3:06:00 AM PDT

Hi Jim,
echoing comments above very useful, recently bought an g5 isight imac 2.1ghz gen 3 from ebay for a play. Thought you might be interested in what I've found.
The imac has had several owners 3 at least that I know of.
Initial state computer bongs and then goes to sleep classic cpu overheating. Screen not working at all so I used the mini to vga adaptor I have.

I first tried target firewire mode with DVD drive disconnected, managed to access harddrive but copying files caused overheat.

Measured the voltages at the power supply connector and the atx style connector seemed ok.

First attemp change the capacitors in the power supply which were
3 x 2200uf 16v
1 x 1000uf 16v

There is one on the primary side but haven't changed that
160 uf 400v

Managed boot operating system turned out to be leopard (advertised as tiger when bought) overheating still occurring with a slow rise over 10 - 15 mins managed to reconnect dvd and still get to desktop.

Dismantled imac reapplied thermal paste to cpu and gpu tried again.

caps on mobo

120uf 16v 2
680uf 16v 3
1000uf 16v 1
1500uf 6.3v 5
1800uf 6.3v 4

Not changed thinking about it.

Imac cpu temperature reduced but still overheating with anything with 100% cpu. Using geekbench as a test sleeps twice.

Whilst running geekbench I started to monitor the 3.3v and 12v at the atx connector thinking the power supply might still be a problem. At extreme temps the 3.3v start to jump around. I got to figuring maybe the power supply was a problem under high load. The power supply had 3 pins out to 5 connectors to the dc - dc board voltage 3.3v 12v and gnd (pwer supply rated at 12.1 x amps no mention of 3.3. Anyway decided to hook up some 12v halogen spotlights I never got round to fitting under a load of 5 x 20w lamps 8 amp the power supply voltage was 11.86 within range as far as I can tell and better than an atx supply I tried with the same load. Think maybe the 3.3v side was a problem I hooked up an atx ps to the dc-dc board connector Heart in mouth and calculating I could sell on the working bits turned it on.
Bong (thankfully).

Using geekbench as a load monitored the 3.3v this time steady even at high load but same result sleeps twice. Concluded original power supply probably now or was ok.

Latest attempt took out mobo again check thermal paste reaplied and looks to have been ok. Removed cpu fan placed 120cm over the hole after blocking the inlet vent and it will actually run geekbench without sleeping still gets to mid 80's deg c.
Do you think it could be caps on board? I did try a mates digital voltage meter on hz setting could detect no frequency indicating ripple but unfamilar with this proceedure.

Curiously the cpu idle temp seems ok high 40's but 100% cpu hits the low - mid 80's.
Anyhow still playing hopefully helpfull to others
Regards
Graham

 

 Ant Harvey (UK) said... At Friday, June 12, 2009 2:48:00 PM PDT

Jim - I think I have the all too common capacitor issue (imac G5 1.8) lines on screen, locks up etc. I have inspected the capacitors with the back off and there is no obvious leakage or bulging. Do duff capacitors always have visible damage? Many thanks, soldering iron at the ready.

 

 Jim Warholic said... At Friday, June 12, 2009 6:24:00 PM PDT

A couple of points here.

Make sure you inspect the PSU caps too.

See the article I wrote about the iMac power supply for more information on that.

If the capacitors on the MOB do not appear bulging, and the PSU caps look OK, and the computer powers up except for display problems like you are talking about, then it is likely that the problem is on the MOB. Capacitors can go bad, and not show signs of bulging. What happens many times, is the electrolyte dries out, and they simply do not filter the ripple current properly.

Some folks have replaced these caps when all else fails, and have been able to bring their iMac back to life. Other times, the problem with the MOB or the PSU is much deeper than the capacitors themselves. But, if it comes to trashing an iMac or spending four or five hundred dollars or more on the MOB and PSU replacement; I would say that you do not have much to lose with trying a capacitor kit.

Jim

 

 Scott said... At Saturday, June 13, 2009 10:28:00 AM PDT

SUCCESS! Just replaced all 29 capacitors, and my iMac G5 is working happily again.

Jim - thanks so much for publishing this information, and for making the right components easy to purchase at a fair price! My compliments, too, for sending the order so promptly - I ordered last Saturday, you shipped them the next Monday, and I received them on Wednesday.

Perhaps this trouble history will help someone else:

I have an iMac G5 ALS model (2nd gen, 2005). After four years of flawless service, it failed to start up earlier this year after a brief power outage. I was able to get it to start after a PRAM reset and a few reboots, and ignored the problem for months. After another power outage, I couldn't get it to come up without booting from a CD-ROM and restarting again several times.

Eventually, it failed again during a restart and displayed the disk-question mark icon, so I figured the hard drive was bad. However, I was able to mount the drive on another Mac using an external enclosure.

After once again multiple rebooting from the CD-ROM, I bought a UPS just to avoid restarting, and the iMac spun happily for another several weeks. Finally, I got the SPOD while browsing, and the system locked up. Recycling the power only brought the gray-screen and 747 fan noise.

After researching iMac problems and discovering your website, I inspected my capacitors, and noted that several were bulging slightly (although none had burst). These were some so-called "good" caps (Chemicon KZJ with a "Y"-vent). I replaced all 29 capacitors, put everything back together and the system booted immediately! Everything is now running normal.

I also have a recommendation for soldering: Since the parts were only about $40 and I was planning to spend at least $600 for a new midplane, I decided to spring for a $160 Hakko 808 desoldering tool from Fry's.
[ http://www.hakkousa.com/AHPDirect/images/808.jpg ]
It surprised me that this tool works beautifully for both desoldering AND re-soldering the capacitors. It's designed for lead-free, and gets plenty hot for the multi-layer board.

I tried a regular pencil-style iron for soldering a couple of new caps, and while I got them in, it was a hassle to get the iron in just the right position to melt well enough to fill the hole, avoiding either a cold joint or lifting a trace.

I decided to try the desoldering tool for the new caps. I had become familiar with how it worked while removing the old ones, and since there is a hole in the tip, re-soldering was a snap using it without the suction. I'll post a detailed follow-up with tips on how to use it.

--ST

 

 Anonymous said... At Thursday, June 18, 2009 10:38:00 AM PDT

I soldered in the new capacitors with a 130 watt trigger iron and they work flawlessly! Thank you for offering these capacitors to resurrect my imac G5 and thanks for the fast shipping! I really appreciate it. These imac G5's "Xbench" test faster than most of the New Intel based Macs including the dual quad core Powermacs So it is so nice to be able to have my imac G5 running great again. Thanks again.
~Johnathan

 

 Andreas Carlsson, Sweden said... At Friday, June 19, 2009 2:20:00 PM PDT

Hi everybody!

I have an iMac G5 20" iSight.

I have the exact same problem as Graham. Ie, CPU temperature rising, fan going mad (3600rpm), and then the iMac turn itself off.

I have replaced the thermal paste, still no go.

I don't understand though, if this is the same problem as what Jim descibes in this article?

Any ideas of what to do would be highly appreciated!

 

 Anonymous said... At Monday, June 22, 2009 9:46:00 AM PDT

I have one of the first Gen 20" iMac G5s. Shortly after I bought it it was overheating and then died. I did some research and found that many had this problem. When I called Apple they said this was not a widespread problem. I sent it back and had it repaired. Now (4 years later) it's messing up again and I opened up and found bulging K caps on the board. I'm not sure what to do. I may see if someone will replace the caps. I have experience with these things but I know how fragile circuit boards are. I will talk to Apple but I am outside of that repair extension timeline.

 

 Marwin Kemp said... At Tuesday, June 23, 2009 8:42:00 AM PDT

I have an original imac G5 (20 inch) with speedy fans. I need to reset the PMU. The back is off but I am not sure where the PMU reset button is. Can you help?

 

 Jim Warholic said... At Wednesday, June 24, 2009 7:37:00 AM PDT

Here are a couple of ways of resetting the SMU. You can reset the System Management Unit (SMU) by pressing the small SMU button on the MOB next to the small internal power on button. See the Apple document for pictures http://support.apple.com/kb/HT2173.

The other way to reset the SMU is to do a special power up sequence by first shutting down the iMac, then unplug the power cord, wait 10 seconds, press and hold the power on button while plugging in the power cord, let go of the power button, then press the power on button again. See the Apple document for more details http://support.apple.com/kb/HT1767.

Jim