Won't Boot: How to diagnose if Logic board or PSU at fault?

Won't Boot: How to diagnose if Logic board or PSU at fault? Model = A1311
Asked by: Guest \| Views: 265

Total answers/comments: 4

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bert [Entry]

"Dan

@danj

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bert [Entry]

"i Found this one. hope you can get an idea as mayer gave wide range answer.

How to determine what is defect if the system doesn't post?"

bert [Entry]

So I have the exact same model of iMac with the exact same symptoms. No chime, no fans, only HDD and DVD are "working". LED #1 is lit. Looking at a reasonably priced logic board. I was thinking of upgrading it to the 2.7GH one. What would you suggest?

bert [Entry]

Only the right-most LED (LED501) lights, and it remains lit as long as the power cord is plugged in. Hitting the power button makes no difference to these lights, but the Fan seems to be running.