Lombard man
Level 1 (145 points)

Q: Imac G5 cpu sensor temperature problem

Hello all. My daughter has a 2005 Imac G5 2.0 GHZ (ambient light sensor) with 1.5 GB  of ram running 10.5.8. Recently it has been shutting down, well going to sleep on her as well as shutting down quite frequently. A problem my old power book had when it kept "overheating" due to a faulty track pad sensor that i had to remove. Well the powerbook thought it was overheating. I restarted it at first, ran disk utility to repair permissions, no good. Then did the pram reset/ No go. Took it apart and blew any dust out of it i could which was very much. Then i tried the smu which controls fans and such. Still have the problem.

 

So i decided to add temp monitor to see whats going on. Thats where i noticed the cpu saying its -37 F degrees!! Which is impossible. When u run something like the browser and a game that requires cpu usage, it will spike all over the place. -37, 40, 110..190.160 back to negatives then to..200. etc. Obviously i think the cpu sensor is malfunctioning. Is there any way to replace this or possibly remove? With my powerbook i opened it up and removed the track pad sensor and never had the problem again. Not sure how the cpu is set inside this. On older g4 towers they were socketed and could easily be change/replaced. Thanks in advance!

iMac, Mac OS X (10.5.8), 17in 2.0 GHZ Imac g5, 1.5 GB RAM

Posted on Mar 11, 2012 1:11 PM

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Lombard man

Q: Imac G5 cpu sensor temperature problem

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  • by a brody,Helpful

    a brody a brody Mar 14, 2012 7:02 AM in response to Lombard man
    Level 9 (66,776 points)
    Classic Mac OS
    Mar 14, 2012 7:02 AM in response to Lombard man

    Temperature sensor software is often unreliable.  The G5s though had another unfortunate problem.  Leaking capacitors.  For that Apple had a power supply replacement program that often included the motherboard.  But that program is long since discontinued.  If you are in the U.S. I know http://www.dttservice.com/ will service those machines that have that problem.

  • by Lombard man,

    Lombard man Lombard man Mar 15, 2012 3:21 AM in response to a brody
    Level 1 (145 points)
    Mar 15, 2012 3:21 AM in response to a brody

    hmm. Yeah im aware of the leaking capacitors. I checked all of them and they all look solid, none busted or cracked or leaking. From what i read you can usually visibly tell if they went bad. I am not sure, oh well cant play it if it keeps doing that. As far as the temp sensor software, it did help me find the problem in my old powerbook and right before it shuts off the fans go super high speed, so it has to do something with the temp sensor or something. Oh well maybe time for upgrade.

  • by a brody,

    a brody a brody Mar 15, 2012 4:37 AM in response to Lombard man
    Level 9 (66,776 points)
    Classic Mac OS
    Mar 15, 2012 4:37 AM in response to Lombard man

    If you do choose to upgrade, note the migration to Intel is not as easy as it might at first appear, but if you take these steps it will be a smooth one:

    https://discussions.apple.com/docs/DOC-2295

  • by sheffi,

    sheffi sheffi Jul 31, 2016 4:33 AM in response to Lombard man
    Level 1 (13 points)
    Classic Mac OS
    Jul 31, 2016 4:33 AM in response to Lombard man

    I had and now have again with iMac 2012 fixed it with SSD Fancontrol ,but also I have experience with many Macs G4 and 5 with Fans temp sensors and dust and keeping them on for long periods, Bad Caps and intensive use.