Fuel Pump Relay: Description and Operation

Fuel Pump Relay Location:

The Fuel Pump Relay is located in relay position #10 of the main fuse/relay panel (see diagram) that is beneath the instrument panel on the drivers side of the car. To reach the fuse/relay panel, pull the upper edge of the recessed storage bin forward and lift out the bin.

NOTE: Some vehicles are equipped with a knee bolster to prevent knee injury in the event of an accident. The knee bolster runs along the entire length of the lower dash. To properly access the fuse/relay panel for servicing, the knee bolster must be removed from in front of the fuse/relay panel.

When the ignition switch is turned ON, battery power flows through the ignition switch to the fuel pump relay. This energizes the fuel pump relay which then closes to supply battery power to the main and transfer fuel pumps, it also provides battery power to the auxiliary air regulator. The fuel pump relay supplies battery power to the pumps for 1 or 2 seconds ONLY then the relay will stop power to the pumps. When the ignition switch is turned to the START position it energizes the relay which then supplies battery power to the main and transfer fuel pumps during cranking. The pumps will stop in 1 or 2 seconds as before unless the relay receives an rpm signal from the ignition system. This rpm signal confirms that the engine is running and keeps the fuel pump relay energized as long as the ignition is ON. The fuel pump relay shuts down the fuel pumps if the engine is not turning faster than 225 rpm to prevent flooding when cranking, and to stop the fuel flow in the event of an accident and fire.