A split-screened, this machine has already been used in a long time, but the Board is still relatively new. First measure the voltage are normal (2.85V), spirit of tackling easier issues first, and after the first peripheral IC circuit maintenance principles, to refresh the software on the phone, but did not repair to completely clean the boards again, trouble still; replaced the central processing unit (CPU). Due to a power management IC, CPU and FLASH too close, in order to ensure quality of maintenance, power IC, also off after reballing installed on FLASH, try fault remains. Open the drawings look, was found in a corner drawing two side buttons, and parallel with pressure-sensitive protective resistor on it, remove the protective circuit, is the protection of the resistance measured leakage current, test machine after you replace it properly.2dWservice manual download site