Why does the diagnostic LED1 turn on after hours?
I've been troubleshooting an old iMac 2011 27". After removing the screen I could use the diagnostic LEDS to gain some info.
When LED1 is on, the machine can be booted without problems. After disconnecting/reconnecting power this LED stays off. It can take hours till LED1 turns back on. After that it boots without a problem.
Am i correct to suspect a bad PSU for this behaviour? I just want to make sure before ordering a piece worth more than the Mac :)
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