Chart A-5 Fuel System Electrical Test

Chart A-5:

Fuel System Circuit:

Fuel Pump Relay Connector:

CIRCUIT DESCRIPTION
When the ignition switch is turned "ON," the Powertrain Control Module (PCM) energizes the fuel pump relay which completes the circuit to the in-tank pump. It will remain "ON" as long as the engine is cranking or running and the PCM is receiving fuel control pulses. If there are no fuel control pulses, the PCM de-energizes the fuel pump relay within approximately 2 seconds after key "ON" or the engine is stopped.
The fuel pump delivers fuel to the fuel rail and injectors, then to the pressure regulator, where system pressure is controlled. Excess fuel is bypassed back to the fuel tank.

CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks the fuel pump relay ignition feed CKT 1042 and ground CKT 251.
2. This step determines if the fuel pump circuit is being controlled by the PCM.
3. This test checks for an open CKT 465.