Chosen Solution
I replaced the back housing on my 3GS, but I can seem to keep the power button from going flush with the housing. It seems to work okay, but doesn’t “click” like it used to. Any suggestions?
I know this an old thread, but I thought I’d put my solution up for anyone reading this in the future: I ordered a new button, and when I looked compared it with the old button, it was missing a little plastic rectangle on the back. I took it off the old button (it just peeled off), and I put it on the back of the new button. When I screwed it all back together, it clicked, when without this plastic rectangle, it didn’t. Hope it helps.
I think taking it apart again and attempting to reseat the button would be your best bet. I can’t think of any other safe/easy way to do it.
Check the Copper Connectors under the Top Half of the Screen