15 - 30 minutes
My mother has had a "stuck" power button for as long as anybody in my family can remember. No amount of Herculean smashing of the power button would make it work reliably. The Apple Store enabled the AssistiveTouch feature, which seemed to me like they covered up the actual problem by slapping on some duct tape. The power button looked fine to my inexperienced eyes, and from reading comments and stories online, it became apparent that the switch on the power and sensor cable was what needed replacing. Tired of hearing complaints about "the poor design of the iPhone", I took matters into my own hands...
One hour and 52 minutes from start (power down) to finish (power on) - faster than expected! This was my first small electronics repair I had ever attempted, so I attribute my success to two things: (1) preparation prior to the repair, and (2) organization during the repair. And some good background music.
PREPARATION: I read iFixit's guide and all related comments thoroughly, making note of all the potential trouble spots in the repair process. I also watched a couple of YouTube videos so I could see how each component came apart, as well as the techniques and forces required to perform the disassembly (the most important part).
FAT (BUTTER)FINGERS: I have sausages for fingers and the dexterity of a newly born giraffe. Magnetized tools, tweezers, and a mouse pad (or any non-slippery working surface) helped enormously.
ORGANIZATION: There were so many little screws and parts that needed to come out that I decided to follow someone's advice and use a large egg crate to keep track of all those pesky pieces (see attached photo). iFixit's guides have great photos and color coded instructions, which I used to label each piece that came out. Not every microscopic screw was the same size or length, so keeping them all in order as they came out made my life so much easier. Especially when I needed to put everything back in....in reverse!
TROUBLESHOOTING: If a step is not going how you had expected, STOP. Take a breath. Read the guide and look at the photos. Pull up that YouTube video again and watch that specific step. Examine your work. Does your technique need to change? Need a different tool? Did you miss or skip anything? No need to rush the repair. You cleared out your schedule, right?
iPhone 4S Power and Sensor Cable
Phillips #000 Screwdriver
iFixit Opening Tool
iPhone 4 and 4S Power and Lock Button
iPhone 4/4S Liberation Kit