The first step is to start debugging the issue. How did it "crash"? What state is the device in at that point? What happened just before the crash (logging, error codes, stack trace etc. might give tell you something about what happened.
how can i read the error codes, what i have try ,1,the voltage is 3.3V , 2,the usb-insert int, the gsensor -int ,all fail, 3, the lcd nothing update when keypress, 4,reset can work,
