Fuel Pump Control - Single Speed MRFS
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The output signal from the PCM controls the electric fuel pump. With the PCM power relay contacts closed, VPWR is sent to the coil of the fuel pump relay. For electric fuel pump operation, the PCM grounds the FP circuit, which is connected to the coil of the fuel pump relay. This energizes the coil and closes the contacts of the relay, sending B+ through the FPPWR circuit to the electric fuel pump. When the ignition is turned ON, the electric fuel pump runs for about 1 second and is turned OFF by the PCM if engine rotation is not detected.