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Fuel Pump Control System (G20)

  1. Turn ignition on. Pinch fuel hose (at filter outlet) with fingers. For 5 seconds after ignition is turned on, pulsation should be felt on fuel hose. If pulsation is felt, system is okay. If pulsation is not felt, go to next step.
  2. Turn ignition off. Disconnect fuel pump relay No. 1 harness connector. See Figure. Turn ignition on. Measure voltage between ground and fuel pump relay No. 1 harness connector terminal No. 1 (Black/White wire). If battery voltage exists, go to step  4. If battery voltage does not exist, go to next step.
  3. Check the following:
    • Check fuse No. 17 (15-amp) located in fuse block under left side of instrument panel.
    • Check for open or short in Black/White wire between fuel pump relay No. 1 and fuse.

    Repair as necessary.

  4. Measure voltage between ground and fuel pump relay No. 1 harness connector terminal No. 3 (Black/Red wire). If battery voltage exists, go to step  10. If battery voltage does not exist, go to next step.
  5. Turn ignition off. Disconnect fuel pump relay No. 2 harness connector. See Figure. Turn ignition on. Measure voltage between ground and fuel pump relay No. 2 harness connector terminals No. 1 (Black/White wire) and No. 3 (Black/Orange wire). If battery voltage exists, go to step  7. If battery voltage does not exist, go to next step.
  6. Check the following:
    • Check fuse No. 42 (15-amp) located in fuse and fusible link box on left side of engine compartment.
    • Check for poor connection at Super Multiple Junction (SMJ) connector terminal 45K (Black/Orange wire). See Figure. SMJ connector is located under left side of instrument panel, behind fuse block.
    • Check for open or short in Black/Orange wire between fuel pump relay No. 2 and fuse.

    Repair as necessary.

  7. Turn ignition off. Check continuity of Black/Red wire between fuel pump relay No. 2 harness connector terminal No. 5 and fuel pump relay No. 1 harness connector terminal No. 3. Also, check circuit for short to ground and short to voltage. If problem is found, repair as necessary. If circuit is okay, go to next step.
  8. Check continuity between body ground and fuel pump relay No. 2 harness connector terminal No. 2 (Black wire). Continuity should exist. Also, check circuit for short to voltage. If problem is found, repair as necessary. If circuit is okay, go to next step.
  9. Check fuel pump relay No. 2. See RELAYS & SOLENOIDS . If relay is okay, go to next step. If relay is not okay, replace fuel pump relay No. 2.
  10. Turn ignition off. Disconnect fuel pump harness connector located behind access cover, under rear seat. Check continuity of Black/Yellow wire between fuel pump harness connector terminal No. 1 and fuel pump relay No. 1 harness connector terminal No. 5. Also, check circuit for short to ground and short to voltage. If problem is found, go to next step. If circuit is okay, go to step  12.
  11. Check the following:
    • Check for poor connection at Green, 10-pin in-line harness connector B102 terminal No. 3 (Black/Yellow wire). See Fig 1. Connector B102 is located behind right kick panel.
    • Check for open or short between fuel pump and fuel pump relay No. 1.

    Repair as necessary.

  12. Check continuity between body ground and fuel pump harness connector terminal No. 2 (Black wire). Continuity should exist. Also, check circuit for short to voltage. If problem is found, repair as necessary. If circuit is okay, go to next step.
  13. Disconnect ECM harness connector. See Figure. Check continuity of Black/Pink wire between ECM harness connector terminal No. 21 and fuel pump relay No. 1 harness connector terminal No. 2. See Figure. Also, check circuit for short to ground and short to voltage. If problem is found, go to next step. If circuit is okay, go to step  15.
  14. Check the following:
    • Check for poor connection at White, 18-pin in-line harness connector F23 terminal No. 2 (Black/Pink wire). See Figure and Fig 2 .
    • Check for open or short between fuel pump relay No. 1 and ECM.

    Repair as necessary.

  15. Check fuel pump relay No. 1. See RELAYS  under RELAYS & SOLENOIDS. If relay is okay, go to next step. If relay is not okay, replace fuel pump relay No. 1.
  16. Measure resistance between fuel pump terminals. Resistance should be 0.2-5.0 ohms at 77°F (25°C). If resistance is as specified, go to next step. If resistance is not as specified, replace fuel pump.
  17. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
Fig 1: Identifying Connector B102 Terminals (G20)
G00103717Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 2: Identifying Connector F23 Terminals (G20)
G00064002Courtesy of NISSAN MOTOR CO., U.S.A.
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