same problem, how I get my HTC sensation 4G broken power button to power on with out a system. step 1: remove the battery from the phone. step 2: plug the phone without battery to a socket using a good cable. step 3: put back the battery when the phone is still connected to power, press and hold the up volume key and just tap on the volume down key while pressing the volume up, when it has on immediately Download volume button as power button
APK
Version: 1.1.1 change your power button to the volume button welcome back start using your phone back