Power button loose/no response
The power button on my 27" 2011 iMac is loose/non-responsive. Since I do not feel any pressure from it (it can actually slide behind the casing a bit and get stuck there), it seems to be broken. I am looking in how to replace it. A lot of info on replacing the power supply, but nothing on the button itself.
Thanks Dan, this helped a lot. I followed all steps to 32. After that I had to disconnect the drive and was able to remove the logic board (carefully). Then I removed the fan and the left speaker. Behind that the actual power button is hidden. I used a hairdryer to soften the glue and was able to loosen the button from the casing (see picture)
The cause of my problem was that the metal ring that is situated between the button and the switch, was shifted (see picture).
This hindered the button from actual reaching the switch. I centered the metal ring, out the button and switch back on the casing and reheated the glue. Firmly pushing it to make sure it stays in plays. Then I reassembled the Mac, and was able to turn it on. All in all a job of 2,5 hours.