Couple days ago I was driving using phone add GPS, in middle of drive in dash mount, no one touching it, it says the Sim card has been removed. So I reboot and it workec fine for a few hours but has been weird since. I read online to try reboot with out sd card. At that point I found that it works without the back cover on. Of I put cover on, it acts like battery is 0 even when 100%.