Chosen Solution
My display wasn’t working. Nor was an external display. The iMac would power up with Led 1 and 2 lit up. Replaced logic board with known working. Now only LED 1 is lit up and machine will not power on. HELP PLEASE. This thing is driving me nuts.
You’ll need to replace the power supply iMac Intel 27" EMC 2546 Power Supply Replacement Its gone
