Mac Troubleshooting: Resetting Macintosh PMU

The PMU is in different locations on different models of G3, G4, G5. If you need to reset Mac PMU, these are some simple instructions to follow if resetting the PRAM ( Parameter RAM ) and the NVRAM (non-volatile RAM) doesn’t work. How to Reset Mac PMU I have collected images to help you locate the PMU.

iMac G3 500 Mhz (Indigo)

Power Macintosh G4 1.0Ghz Dual Processor (Mirrored Drive Doors)

Power Macintosh G4 667 Mhz (Graphite)

Power Macintosh G3 350 Mhz (Yosemite)

Power Macintosh G4 450 Mhz (Graphite)