Fuel Pump Relay: Description and Operation

Circuit Opening Relay Schematic:

PURPOSE
The circuit opening relay provides power to the fuel pump.

LOCATION
Located behind the center of the dash, mounted to the ECU.

CONSTRUCTION
The relay consists of a single set of contacts controlled by two separate coils.

OPERATION
One coil is energized when the key is turned to the start position. The relay contacts close and power is supplied to the fuel pump for starting. Once the engine starts, the air flow sensor grounds the other coil which continues to hold the contacts closed after the key is released to the run position.