Fuel Pump Control System (Q45)
- Turn ignition on. Pinch fuel hose 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.
- Turn ignition off. Disconnect fuel pump relay. See Figure. Turn ignition on. Measure voltage between ground and fuel pump relay harness connector terminals No. 1 (White wire) and No. 3 (Black/White wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit. See appropriate diagram in WIRING DIAGRAMS article.
- Turn ignition off. Disconnect fuel pump, Fuel Pump Control Module (FPCM) and dropping resistor harness connectors. See Fig 1 and Fig 2. Fuel pump harness connector is located in bottom of trunk. Check continuity of Black/Yellow wire between fuel pump relay harness connector terminal No. 5, FPCM harness connector terminal No. 3 and fuel pump harness connector terminal No. 1. If continuity exists, go to next step. If continuity does not exist, repair open in Black/Yellow wire.
- Check continuity between ground and dropping resistor harness connector Black wire. If continuity exists, go to next step. If continuity does not exist, repair open in Black wire.
- Disconnect PCM harness connector. See Figure. Check continuity of Black/Pink wire between fuel pump relay harness connector terminal No. 2 and PCM harness connector terminal No. 42. See Figure. If continuity exists, go to next step. If continuity does not exist, repair open in Black/Pink wire.
- Check fuel pump relay. See RELAYS & SOLENOIDS . Replace if necessary. If fuel pump relay is okay, check fuel pump. See FUEL PUMP . Replace if necessary. If fuel pump is okay, go to next step.
- No problem is indicated at this time. Problem may be intermittent. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
Courtesy of NISSAN MOTOR CO., U.S.A.
Courtesy of NISSAN MOTOR CO., U.S.A.