Phone 6s touch id doesn't work when charging on a grounded outlet. Touch ID does work if charging on ungrounded outlet or unplugged. Apple store replaced the front panel. Took it home with same result. Apple sent me a new Iphone 6s. After setting up the phone said there was a system update to 9.2.1.. I did the update. So far everything was working well, including touch id. The next day I plugged the phone into a grounded connector. No touck id. Unplugged it. Have touch ID. Same exact problem I had to beging with, with a completely different Iphone 6s. Apple doesn't seem to know what to do about it. Anybody have any sane ideas?