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How do I change the power button of my iMac 21" My iMac has a power button problem. I have to keep pressing it until it starts. I think it is an issue with the Button from the first day. It’s a 2010-2011 model. Does Apple have an out of warranty solution for this? Personally, I think the power button should be replaced. How to do this?
You may have a logic board or power supply problem. The power switch is a soft switch design. It uses a low voltage logic to then fire off a relay on the power supply which then turns on the computer. If you are able to use a multimeter you could take a measure of the switch to see if its working and you can also check the rest of the circuit. Follow this IFIXIT guide: iMac Intel 21.5" EMC 2428 Logic Board Replacement. Jump down to Step 22 and locate the Purple marked connectors. The lower one is the power switch.
