XYMer's Home away from Home

Historical note: This is old information, but I'm posting it so that anyone who might be looking for it in the future can find it. Apple has a bad habit of "disappearing" this kind of stuff.

Apple released a repair extension authorization program -- basically an extended warranty on certain components that may experience a particular type of failure -- for three years from the date of purchase for first generation iMac G5s with serial numbers with the first five digits in the following ranges:

• W8435 - W8522
• QP435 - QP522
• CK435 - CK522
• YD435 - YD522

The program covered machines, as Apple put it, "sold between approximately September 2004 and June 2005 featuring 17- and 20-inch displays with 1.6GHz and 1.8GHz G5 processors."


The problems were principally caused by faulty capacitors on the motherboards (midplanes) and inside the power supplies. I don't know for certain if any other components were causing problems on these systems.

Apple states: "as of December 15, 2008, this program is now closed."

If you're experiencing these sort of problems your first generation iMac G5, open the computer and check for bad capacitors on the motherboard and/or power supply. The capacitors are not difficult to replace if you have at least basic soldering skills and some patience. If you decide to replace the bad capacitors, remember to replace all the capacitors not just the ones that are obviously faulty. Any bulging capacitors, or any with brownish or any other color gunk leaking out of them, are definitely bad, but if you see one bad capacitor, suspect all the others. The absence of obvious signs of failure does not mean a capacitor is working correctly.

IMPORTANT: It can be a pain in the butt to open the power supply if you don't have the right Torx security screwdriver. You also must promise that you or your heirs won't sue us after you electrocute yourself.

If your computer tends to shut down unexpectedly and nothing else is obviously wrong, it's almost certainly due to the aforementioned problems and either a power supply or motherboard repair will be necessary. If after the unexpected shutdowns you see entries in your system.log (which you can browse in the console) like "AppleSMU -- shutdown cause = -110" (other numbers are possible) then you almost certainly need to repair or replace the motherboard and/or power supply.

If your computer is unexpectedly going to sleep, it's probably overheating. This could be caused by a bad thermal connection to the heatsink, faulty temperature sensors, or an airflow problem like a bad fan or clogged vents.

I'll continue to update this thread as needed.

- Anonymous

Great idea for a post non!

Orchard Supply Hardware—that’s “OSH” to you and me.

-he who stacks pork

Fortunately, it didn't come to this for me, but stumbled on this. There's a wealth of information on doing this repair, including soldering technique, and many links, including one where you may find an exact replacement set of all the caps. This set is supplied, supposedly, with the correct physical dimensions for fit. I can"t vouch for this first hand, but it would seem worth looking into.

http://jimwarholic.com/2008/07/how-to-r ... mac-g5.php

Great link/addition WZZZ, thanks!

So, a 20" iMac (G5) with a serial number QP537..., and a 2 GHz processor is probably okay? I have an opportunity to get one of these for free (part of a deceased brother's estate), but I don't want a ticking capacitor time bomb.

It's probably fine. And even if it does eventually crap out, you'll have enjoyed it quite a bit in the meantime. The 20" iMac G5s are lovely machines when their capacitors aren't leaking. The 20-inchers also don't have, in my experience, the fan noise problems that the 17" models often suffer.

Unless you don't have the space for it or you're using something better, I'd jump at that opportunity.

- Anonymous

Can you explain what causes that problem when it occurs? (As I mentioned elsewhere, I was concerned about an opposite problem, that I usually didn't hear any fan sound--checked using Hardware Monitor, and all the fans are operating properly. This 17" (first generation) is ultra quiet.)

Actually I'm using a dual 2 GHz G5 tower, but I'll find room for this (in my small place) somehow. It has finally reached the point that when another computer moves in, one moves out. I'll find someone to give the QS 933 to. This will leave me with the G5 tower, Dual boot MDD G4 1.25 GHz, a 1 GHz dual boot PowerBook G4 and a Cube along with that iMac! Wow. I remember when I had my first Classic II, then Quadra and would look a folks with multiple machines in awe, and now I are one, LOL.

Dell's bad caps leaking out now big time.
"In Faulty Computer Suit, Window to Dell’s Decline"

http://www.nytimes.com/2010/06/29/techn ... wanted=all

My experience is that appears to be Apple's approach to product flaws, although I don't know if Apple specifically did that once the capacitor problems were identified.

- Anonymous

I remember having a designer come to me with one of these leaky beasts and having to order up the new board and install it. Sort of a pain, but not too bad, ultimately, and a good experience tearing into one of those cases. Engineering to the extreme for the time.

Great post and idea, Anon.

Mine, as you may know, plowed through three boards. Every few days there's a post on the iMac G5 Apple forum from someone who had the board or the power supply replaced, either self-paid or by Apple, who's now having the same problem.

Here are some very interesting photos from a guy who said his board was replaced by Apple and which failed again within a few months. He took it out and was rather astonished. Be prepared to see some really nice work. Someone who knows how to work on these commented if it was done by Apple, it must have been by the troglodyte division.

Unless I'm mistaken (and I certainly could be), most of those photos are showing flux resin, which is included in solder and flows all over the place when you solder in new parts. It's possible that part was repaired multiple times, each time leaving behind more resin.

All the gunk is definitely leftover flux. It really probably should have been cleaned up. The solder jobs was also not very good, but I'd guess it'll hold. My suspicion is that it probably wasn't done by Apple. I'd bet Apple pulls the boards, puts in a "new" (or refurbed) one, and sends the old board to some facility for reconditioning. Anyplace repairing a lot of these will probably more-or-less know what they're doing and have a nice rework station for doing it, plus likely enough experience to know how to solder things nicely.

- Anonymous

It was probably repaired by monkeys, who don't know how to clean up the flux (I don't, but then again I don't do it for a living).

Most/All of the remanufacturing work is outsourced now, I wouldn't be surprised if those parts got shipped to Mexico. Not to say that they can't do good work down there, just that they'll just do the work for virtually nothing, which doesn't lend itself to retaining personnel who know what they're doing.