Modern vehicles use the Coil-In-Plug (COP) system. This system is based on a coil in each cylinder which is controlled by the Powertrain Control Module (PCM).
The coils have 2 wires: one is for battery power, and it is controlled by the power distribution center, while the other wire is from the coil activation circuit that comes from the PCM (Powertrain Control Module).
The Powertrain Control Module turns this circuit on or off to activate and deactivate the fuel pump.
The PCM constantly monitors the circuit of the coil controller, if you find faults in the circuit of coil number 1, for example, a short circuit, the DTC code P0351 OBDII is set. It should be mentioned that depending on the vehicle model, this code may be set by the fuel injector.