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Fuel Pump Electrical Circuit

When the ignition switch is turned to the ON position (before engaging the starter), the VCM energizes the fuel pump relay for 2 seconds causing the fuel pump to pressurize the fuel system. If the VCM does not receive the ignition reference pulses (engine cranking or running) within 2 seconds, the control module shuts off the fuel pump relay, causing the fuel pump to stop. The VCM will also turn ON the fuel pump for 2 seconds when the ignition switch is turned to the OFF position.