Fuel Pump Electrical, Testing

Fuel Pump Electrical, Testing

Special tools, testers and auxiliary items required

• Multimeter.

• Diode test lamp

• Electrical connector test lead set.

Test conditions

• Battery voltage at least 12.5 V

• Fuel Pump Fuse S-13 is OK.

• Refer to Wiring Diagrams for circuit/component references.

• Low Fuel Pressure Sensor (G410) OK.

Test procedure

- Observe safety precautions. Refer to => [ Safety Precautions ] Safety Precautions

- Observe Clean Working Conditions. Refer to => [ Clean Working Conditions ] Clean Working Conditions

- Perform a preliminary check to verify the customers complaint. Refer to => [ Preliminary Check ] Preliminary Check.

Test sequence

- Switch ignition ON. Fuel pump should run for approx. 2 seconds.

- Switch the ignition OFF.

If Fuel Pump does not start up:

- Remove the fuel delivery unit cover located under the right rear seat. Refer to the Repair Information for seat removal.

- Disconnect the T5 connector from Fuel Delivery Unit (GX1).

- With a test lamp connected to B+, probe terminal 4 (ground) of the T5 connector. The test lamp should light. If the lamp does not light, repair the open circuit to ground. Refer to wiring diagrams.

- Switch ignition ON.

- Connect a voltmeter to ground and check terminals 1,2,3 for voltage.

Specified value: 3.6 V (+/-.4 V).

- Switch the ignition OFF.

If the specified value was obtained:

- Replace the Fuel Delivery Unit (GX1). Refer to the Repair Information.

If the specified value was Not obtained:

• The Fuel Pump Control Module J538 is located on top of the fuel tank and will require the tank assembly be removed to access the control module and harness. Refer to the Repair Information for removal procedure.

- Using a multimeter, check the Fuel Pump Control Module (J538) harness connector to the Fuel Delivery Unit (GX1) harness connector for open or high resistance. Inspect the wiring harness insulation for rub through.






Specified value: 1.5 ohms max.

If the specified value was Not obtained:

- Repair the open circuit or replace the Fuel Pump to Control Module harness.

If the specified value was obtained:

- Leave the Fuel Pump Control Module (J538) and the Fuel Delivery Unit (GX1) disconnected.

- Switch the ignition ON.

- Connect a test lamp between terminal 5 (12v supply) and terminal 6 (ground) of the Fuel Pump Control Module (J538) T6 harness connector. The test lamp should be ON.

If the lamp was Not ON:

- Check the circuit from fuse S13 to the Fuel Pump Control Module (J538) terminal 5 for an open, high resistance or short to ground. Repair the circuit as necessary.

- Check the ground circuit from the Fuel Pump Control Module (J538) terminal 6 to ground for an open or high resistance. Repair the circuit as necessary.

If the test lamp was ON:

- Replace the Fuel Pump Control Module (J538).

Final procedures

After repair work, the following work steps must be performed in the mentioned sequence:

1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Modes 01 - 09.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.