Car mode in android
I recently started having issues with 'car mode'. The phone will seemingly randomly switch to this mode, which shows a big clock floating on a black screen, and a little steering wheel in the notification bar. It makes all calls go to speaker phone, and activates 'talk back' services.
After reading a number of forums I concluded that this error is caused by a faulty mini USB port in the phone. There is apparently some sort of short circuit that makes the phone think it is in a car dock.
The solution which seems to have worked fairly well was to clean the USB port with a toothbrush, and compressed air. I also disassembled the phone to tighten the two screws holding the USB board in place.
Thanks to this video, my backup plan is to order a replacement USB board for a few bucks, making sure to carefully match revision and batch numbers with my original.