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Fuel Pump Relay: Description and Operation



PURPOSE
The Circuit Opening Relay provides power to the fuel pump.

OPERATION
The Circuit Opening Relay consists of a single set of contacts controlled by two separate coils. 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 Control Module (ECM) begins to receive a signal from volume airflow sensor it grounds the other coil which continues to hold the contacts closed after the key is released to the run position.