Fuel Pump Relay: Description and Operation

Schematic View Of Circuit Opening Relay Circuit:

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

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

OPERATION
One coil is energized when the ignition switch is turned to the START position. The relay contacts close and power is supplied to the fuel pump for starting. Once the engine control module (ECM) begins to receive pulses from the crankshaft position sensor (NE signal) it grounds the other coil which continues to hold the contacts closed after the key is released to the RUN position.