How to fault-find iMac A1174 20" intermittent boot issue
by DrM4TT - 3/31/12 4:52 AM
After a year of non-use, worked fine. Then after several uses, intermittent refusal to boot. Sometimes would, sometimes as stubborn as a mule. Unplug 15s, replug wait 5s. Sometimes Y, sometimes N. But then come back to it later and it would boot.
Then one occasion power went during operation. No life. Taken apart following this (1st class honours in electronics, admittedly 23 years ago) changed CR2032, looked for blown caps, checked in/out voltages and bridge rectifier on PSU all good. Reassembled, started immediately. Next day, dead as a dodo. Suspect main logic board rather than PSU, but what do I know? About this fine beast, I know that I know too little.