This fault code is related to the electrical system of the fuel volume regulator. These systems consist of the fuel tank, fuel pump, lines, filter, and injectors.
The high-pressure fuel pump aims to increase the fuel pressure required for the fuel rail and injectors. Besides, these particular pumps have both, a low-pressure side and a high-pressure side, and of course, these pumps have a fuel volume regulator to control the pressure. The DTC code P0002 OBDII means that an electrical reading has been detected which is out of range.