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My iMac won’t boot. Tried resetting SMU. When I plugged power cord in and held power button, there was a loud “pop”. I have taken the bezel off to check diagnostic lights. No lights come on when power cord plugged in. I would be grateful for any ideas.
The diagnostic LEDs to the right of the RAM slots (this may be covered by a piece of black electrical tape). LED Startup Sequence LED #1 = Power available. If no LED is visible: • Verify AC source • Verify known-good AC cable is connected • Verify cable connection between AC inlet and power supply • Verify cable connection between power supply and logic board • Verify power supply LED #1 + LED #2 = Power available, and system is powered on. If second LED is not visible when power button is pressed: • Verify power button connection to logic board • Verify power button functionality • Verify cable connection between power supply and logic board • Verify power supply • Verify logic board LED #1 + LED #2 + LED #3 = Power available, system is powered on, and video card found. If third LED is not visible after power on: • Verify that MXM video card is seated properly • Verify logic board If no lights are coming on you need to replace your power supply. A trickle charge is sent from the power supply to the first LED. If the first LED is not lit the power supply is not working.
I have a question. Currently I’m having the same issue I ordered a power supply, installed it but that did not work. I even ordered a different power supply that still did not work. I’m not getting any LED’s lighting up. Any other suggestions?
