Question about Apple iMac G5 Desktop

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HD Temp.Sensor problem

Received an error message in Apple Service Diagnostic - Ambient Temperature error -25128
so I replaced the HD temperature sensor and cable but still get the same error when I run Apple Service Diagnostic again. The Hard Disk Temp.Sensor does not show up in Temperature Monitor or iStat. Computer behaving well mostly but sometimes will not startup, stays on black screen with front light on.
iMac G5 20" PPC 1.8 ghz V.1 2005

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  • marieyates Apr 05, 2009

    Yes, I know there is more than one sensor in the unit - the others are all showing fine in Temp Monitor

  • marieyates Apr 05, 2009

    I replaced the HD Temp monitor and cable but it still does not initialize at Startup and fan is running slowly all the time - I can feel it - any suggestions? CPU and SMART sensors showing up nicely and working fine.


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There is more than one sensor in the unit, the other two are part of the logic board and can't be changed unless the logic board is changed.

Posted on Feb 22, 2009

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