iMac G3 Graphite 700MHz not booting, possibly cooked

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phlogios

Tinkerer
Jun 30, 2022
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The battery was not the culprit. I tried with 3 new batteries and it didn’t work. Pressing on the BGA with a few kilograms of force helped, but only for a few seconds.
 

PotatoFi

Active Tinkerer
Oct 18, 2021
181
373
63
@phlogios I have an iMac DV here with the same symptoms. Connect power, there's a very small degauss sound, and then a moment later the sound of static as if the CRT has stopped receiving power.

Trickle at J9 is good, -1.2v at DCO checks out (didn't try power-on, not enough hands). New battery and PMU reset - nope. Fuse is good. No obvious bad capacitors. Not sure what else to try on this one.
 

PotatoFi

Active Tinkerer
Oct 18, 2021
181
373
63
My iMac G3 has been plugged in for a solid week now, and sadly there has been no improvement.
 

phlogios

Tinkerer
Jun 30, 2022
33
31
18
My problem was not on the CPU, I don't know the name of the component. It had a big grey aluminum heatsink, in the center of the logic board. The CPU is to the left of that component, and mounted on the bottom side.