You must have encountered this situation : Sometimes your home button just fails to respond when you press it, no matter how hard you had try ,it remain unresponsive. And then you will see your phone jump up with a screen notification saying your “home button may need service” and provide an onscreen home button to use. Regrettably but it can be sure that your home button might get into some trouble. If this is the case, this guide might provide you with a quick way to get rid of the trouble caused by a broken home button or namely home/Touch ID sensor assembly.
1. Power off your iPhone before disassembly.
2. Dismantle the display assembly. Opening the iPhone's display will compromise its waterproof seals. Take extra care not to expose your iPhone to liquid damage after completing your repair. As for the way of dismantling the display assembly，you can search through the internet or visit here for help.
3. Remove the four Y000 screws securing the bracket over the home/Touch ID sensor: One 1.1 mm screw; three 1.3 mm screws.
4. Remove the bracket that secures the home/Touch ID sensor.
5. Lift the home button connector to the right to disconnect it from its socket on the interconnect cable.
6. Gently move the home button interconnect cable out of the way of the home button cable. Don't try to detach the press connector completely—simply lift it up so that it is out of the way when removing the home/Touch ID sensor cable.
7. Flip the display assembly over, and apply a warm iOpener to the home/Touch ID sensor area for about 90 seconds. This will also help soften the adhesive holding the delicate sensor cable in place. A hot Air gun or hair dryer proved to be much more convenient and is a time savior. You can heat more and the glue becomes more fluid make the next steps with the opening picks much easier.
8. Use an opening tool pick to gently separate the adhesive holding the home/Touch ID sensor cable to the back side of the display panel.
9. Remove the old home/Touch ID sensor assembly.
10. Reinstall the new one in reverse order.
Replacing home button is a relatively complex operation requiring your patience and carefulness, and what is worth noting is that in most cases replacing the sensor with a new one will cause the loss of fingerprint sensor functions, but if properly handled, it can be good as new, Touch ID and all.