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Checking indicator lights I Plug the iMac in, LED 1 would light up; press power button then LED 2, 3 and 4 would turn on then all LEDs turn off Would appreciate help
This sounds like you have a bad capacitor on the logic board. This will take a bit of effort to nail down. You’ll need to find the schematics and board view drawings to trace out the voltages. Your other option is getting a replacement logic board.
