Anyone else with iMac G5 sudden shutdowns?

Discussion in 'PowerPC Macs' started by eji, Feb 8, 2007.

  1. eji macrumors 6502


    Jun 8, 2004
    Inland Empire
    I've just made arrangements for my iMac G5 to be taken in for repair (probably power supply replacement) on account of sudden shutdowns.

    I had found these two threads (first, second) when the problem first started appearing, and I'd like to know how many others have been affected by the problem. This faulty power supply is part of a worldwide repair extension program, so I thought the numbers of affected users might be a bit higher than three.

    The symptoms, at least as I experienced them, were as follows:

    - 20" iMac G5 ran fine for a more than a year and a half. No problems at all.

    - One day this past November, it simply shut down -- *blink* -- a few minutes after reboot. I had just installed some media software that affected screensaver and sleep settings, so I thought that was the cause. It shut down two more times after reboots. On the third try, I reset the SMU and deleted energy saver .plist settings.

    - Ran fine for a few days, then shut down again suddenly.

    - Ran fine all through December and January.

    - Last week (early Feb), it shut down as I was watching a video and running a bunch of other apps. I thought it might have something to do with the fact that I hadn't really run it hard for the past two months. (But still, I'd expect a kernel panic rather than a sudden shutdown if that were the case.)

    - This past Tuesday, shut down right after it booted. Ran fine for the rest of the evening.

    - Yesterday evening, it shut down after being on a few minutes. Then it shut down at the login screen after a reboot. Then it shut down again within mere seconds of being turned on.

    - I left it off and didn't touch it again. Called AppleCare.

    So, has anyone else been confronted with this and sent their iMac in for repair? (Misery loves company.) Or are you experiencing any of these symptoms and wondering what the hell's going on? (Hope this thread might be of help.) Or has it been smooth sailing all the way? (You lucky dog, you.)
  2. moritz macrumors newbie

    Dec 22, 2006
    I own a 9 months old 17" intel imac. Same problem. Sent for repair 3 times. Firts time they told me they cannot find any fault with the hardware. Second time they changed the logic board. Third time they changed the power supply. So far no more problem.
  3. CptnJustc macrumors 6502

    Jan 19, 2007
    Is this a total shutdown, or does it go into sleep mode?
  4. amiga macrumors 6502


    Jul 12, 2006
    Had my locic board replaced too... Well my iMac. It's fine now. It was under a year old at the time but it took them about 2 months to fix it! Boycot Computre warehouse (London) Boo, I've had a few bad experiances with them!
  5. eji thread starter macrumors 6502


    Jun 8, 2004
    Inland Empire
    Total shutdown. As in, complete power off. No pulsing sleep light, nothing.
  6. macrumors newbie

    Apr 10, 2004
    iMac G5 sudden shutdowns

    Similar experience:
    18 mo old iMac G5

    First: Would'nt boot, until left unplugged few hrs, then plugged & restarted
    Next: Random shutdowns, with increased frequency

    I figure Apple won't be able to diagnosis until completely dead so I am continuing to run it until so...

    [Crazy thing is I am now having Random Shutdowns with my 6 week old Macbook. Add to that, a seemingly unrelated problem with one of four La Cie Drives I'm using (a 250 Gig); the drive (as soon as connected to the MacBook)causes it to do the dreaded "Must restart your computer" thing. I thought I had lost all the EyeTV programs I'd recorded. I tried all kinds of stuff until I connected the drive to my old G3-466 iBook (w/ an older version of OSX) and lo and behold the drive works, and I'm busy backing up my fav TV files. BTW what drive should I replace the LA Cie with?? (250 Gig and up) ]

    So what gives?? Is this an OS X Problem?? Seems strange that I am having Random Shutdown problems on two different Macs. I was really leaning toward a power supply explanation for the G5, that is, til the MacBook .........

    Thanks, in advance, for any advice.
  7. eji thread starter macrumors 6502


    Jun 8, 2004
    Inland Empire
    Well, if you're asking for advice...

    I think you should do something with the iMac ASAP. Apple has acknowledged that there's a problem and will foot the bill for repairing affected units, so why put up with something that clearly shouldn't be happening? I mean, this kind of garbage is why I ditched PCs six years ago -- I put up with sub-par or even poor performance and made all kinds of excuses for the manufacturer. Besides, sudden shutdowns are not at all good for the machine, hardware- or software-wise.

    And if it persists with the MacBook, send that in as well.

    As far as I know, this isn't an OS X issue. It's a hardware issue in all chronic cases.
  8. zap2 macrumors 604


    Mar 8, 2005
    Washington D.C
    I'm on my 3rd time its happened, each time Apple fixes, and the same problem of these day hopefully Apple will say "Here is your new Intel iMac!"
  9. eji thread starter macrumors 6502


    Jun 8, 2004
    Inland Empire
    That, my friend, is crap. I'm really hoping I don't have one of the repeat offenders. New power supply, maybe new logic board, and then a few more years of trouble-free use.

    I really wish that the rest of the US would enact similar laws to California's "3 Strikes" for defective merchandise. That is, if it ain't fixed by the third try, you get a brand new device. I have no idea if that works in practice, however, or if it's just a law that exists on paper or in legislative mythology.

    Do you have AppleCare, by the way? In my own limited experience, I find that AppleCare can sometimes get you VIP treatment.
  10. zea mays macrumors 6502

    zea mays

    Feb 10, 2007
    I just had my 20 inch Rev A iMac G5 at the Genius Bar tonight. I had been having the power supply problems and today my computer would not boot (seriously bad....blinking folder and question mark bad). They replaced my power supply unit which had a couple blown capacitors (same issue caused my logic board to be replaced around a year to year and a half ago) and my hard drive was fried. All covered under my AppleCare and the powre supply extended warranty. Super easy and I was in and out in less than two hours.
  11. nose macrumors newbie


    Jan 12, 2007
    Asheville, NC
    my Rev A 17" iMac G5 1.6 Ghz does something like this. I do not think I have ever noticed it do it while I was on the computer but when I have left it on for awhile(mostly while I'm asleep) it will shut down. It was doing it frequently for awhile and I'm not sure if it's doing it at all right now. I have it set to reboot back up if a power failure has occured. home power failure is not the problem cause I have seen it do it a few times. usually I notice that it has done it because all me apps will be closed out. I'm not sure what is going on here. could I be having the same problem?
  12. decksnap macrumors 68040


    Apr 11, 2003
  13. eyedoc_00 macrumors regular

    Jun 25, 2005
    My iMac G5 rev b had this problem. I took it into an apple store and they repalced my logic board and power supply. All is good.
  14. NewtypeCJ macrumors 6502


    Feb 27, 2005
    Decatur, GA
    I started getting this problem about a week and a half ago. My 20" iMac G5 (bought in May '05) just *blink* shut down right before my eyes. Ever since if I left it on too long it would just shut off again. Very annoying.

    I checked the Apple Support site and saw that there was a repair extension. So I checked my EMC # and it matched that of the effected units. I figured I was in the clear and a repair would be fast and free, so I made an appointment at the local Apple Store and took it in. They opened it up and saw I had third-party (Crucial) RAM installed and began blaming that. But I'd installed that right when I got the computer -- it was never booted with the original Apple RAM -- and it'd run fine for the last two years. They didn't see any problem with the power supply from just eyeing it, and told me that the defect units had some other mark on them (mine has "K," I guess the bad units have something else?).

    Anyway, they're looking into it now. I don't have AppleCare, which is my mistake for not buying it in time.

    Anyone think it could be my RAM? Really? Never heard of that before.
  15. eji thread starter macrumors 6502


    Jun 8, 2004
    Inland Empire
    Mine has the newer "K" capacitors too. But it was the power supply in the end. It's been running beautifully since.

    Whoever the goons are at the Apple Store, tell them it's the power supply. Because that's clearly what it is. It's not RAM. And you don't need AppleCare if it's a general recall or repair extension, so don't kick yourself for not buying it.
  16. nsbio macrumors 6502a


    Aug 8, 2006
    Blaming third party memory is one of those sly stratagems to avoid fixing the hardware even if it is malfunctioning not due to bad RAM. I wonder if it is even legal to harass customers like that. In effect this is a very nasty sales pitch to buy the overpriced Apple memory. Are other computer manufacturers doing the same thing (I honestly do not know)?

    For future, you should always remove 3-rd party memory before bringing a Mac in, regardless of the exact nature of the problem, to avoid hassles with Applecare.
  17. kyuzo macrumors newbie


    Nov 15, 2007
    iMac sudden shutdown

    My iMac 20" have a random sudden shut down too, i had it by a month and i cant use it because she shutdown after one hour or three

    someone can help me please, because i take the iMac to the Apple store and they didt find anything...
  18. eji thread starter macrumors 6502


    Jun 8, 2004
    Inland Empire
    Is it an iMac G5 or a white Intel/aluminum iMac?
  19. Roger in NYC macrumors newbie

    Nov 26, 2007
    Thanks, I have the same problem (and was going nuts)

    Thanks for the complete explanation and the link to the power supply replacement page at Apple!

    I was going nuts, my PPC 20" G5 iMac started shutting down randomly a couple months ago. An Applecare merely suggested zapping the PRAM, which fixed it for a little mention that the power supply was a lemon.

    THEN, after updating to OS 10.5, the problem occurred again. At first once a week or so, and lately several times a day. Exasperating!!

    I don't know why I couldn't find the page you've linked to on the Apple site, but I'm sure glad you linked it. After over an hour on the phone with Applecare, I mentioned that other threads on the Forum, which suggest a power supply or logic board problem. After a long time on hold while they looked into it, they asked me to look at the number on the base (pretty much exactly what the linked page suggests). Yep, it's a match! My power supply blows! Yippee, at least now there's a likely solution.

    Remarkably, I don't think the phone helper would have EVER got to this without my prompting. I only found your thread because of the long, long wait for and during the call, and had actually determined that I have a lemon power supply before the Applecare rep had got back on the phone.

    That I could beat the Applecare rep to the solution (with your help) is made even more ridiculous by the chance shut down once DURING the call...even with my Mac shutting itself off, I found out what the problem was in less time than the phone "experts."

    So, thanks again!

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