Fuel Pump Relay

PCM energizes fuel pump using fuel pump relay. Fuel pump relay is located in PDC, near radiator coolant recovery bottle. For fuel pump relay location within PDC, refer to PDC cover label. Fuel pump relay coil is powered when ignition switch is in RUN or START position. Fuel pump relay is controlled by PCM switching fuel pump relay and common ASD relay coil ground on and off.

Fuel pump circuit is completed during cranking and whenever engine is running. If ignition switch is turned to RUN position, fuel pump will operate for one second and then shut off. If PCM does not receive a crank or run signal, it deactivates fuel pump by opening relay coil ground circuit. One second time limit is used to prevent unnecessary operation of fuel pump once system is pressurized. If engine is running, PCM maintains fuel pump relay coil ground allowing continuous operation of fuel pump.