Chosen Solution
My iphone 3gs got wet a few months back. I took it apart and dried it out and got everything working except the power button on top and the camera. So I ordered a new camera module and a volume/headphone/power button flex cable assembly and replaced the parts. Now the camera works fine, but the power button still doesn’t work. All the other parts of the flex assembly work, like the headphone jack, the mute/vibrate button, and the volume control. The power button is still non functional though. It clicks very well, but nothing happens. What could be the problem here? Just in case it helps, I’ve found that one of the little flex cables that connects the display to the logic board (I think it is labeled ‘3’) doesn’t seem to really go in the way it should and appears loose. This is probably unrelated as the teardown for the 3gs seems to indicate that the ‘3’ cable is for the ear speaker, but I thought I’d mention it..
try loosening or tightening the screws on the power button flex
I am in the same boat you are. Everything works fine on my 3GS, except the sleep/power button, and it clicks fine, just no response. I really only care about taking screen shots and without the button functioning, it cannot be done.
same boat. new bottom half, with cables and all, so it appears that the sleep/power button failure is on the mobo. I wish I had a diagram of the connection points where the flex ribbon connects, as I think this is where the problem is - on the main board. Anyone?
