Fuel Pump Relay: Description and Operation

The PCM controls the fuel pump relay by supplying switched ignition voltage to the fuel pump relay coil. When the ignition switch is first turned On, the PCM energizes the fuel pump relay. The relay contacts close applying power to the fuel pump. The fuel pump relay will remain On as long as the engine is running or cranking and the PCM is receiving reference pulses. If no reference pulses are present, the PCM de-energizes the fuel pump relay within 2 seconds. With the engine stopped, the fuel pump can be turned On with a scan tool.

If the PCM detects a problem on the relay control circuit, DTC P0230 will set. Use this table if DTC P0230 is not set and a problem exists with the fuel pump.