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Fuel Pump Control System

  1. On Quest, check inertia fuel shutoff switch located behind left kick panel. If switch has been triggered, push reset button. If switch has not been triggered, go to next step.
  2. On all models, turn ignition on. Pinch fuel hose with fingers. Pulsation should be felt on fuel hose for 5 seconds after ignition is turned on (one second on Maxima). If pulsation is felt, system is okay. If pulsation is not felt, go to next step.
  3. Turn ignition off. Disconnect fuel pump relay harness connector. For location, see ECCS, PCM & FUEL PUMP RELAY LOCATIONS  table under RELAYS & SOLENOIDS. Turn ignition on. Measure voltage between ground and fuel pump relay harness connector power supply terminals. See FUEL PUMP RELAY CIRCUIT IDENTIFICATION  table. 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.
  4. Turn ignition off. Disconnect fuel pump harness connector. For location, see FUEL PUMP HARNESS CONNECTOR LOCATIONS  table under FUEL PUMP. Check continuity of fuel pump ground circuit. See FUEL PUMP CIRCUIT IDENTIFICATION  table. If continuity exists, go to next step. If continuity does not exist, repair open ground circuit.
  5. Check continuity of fuel pump power supply wires between fuel pump harness connector and fuel pump relay harness connector. See FUEL PUMP RELAY CIRCUIT IDENTIFICATION  and FUEL PUMP CIRCUIT IDENTIFICATION  tables. If continuity exists, go to next step. If continuity does not exist, repair open in appropriate wire.
  6. Disconnect PCM harness connector. See Figure, Figure, Figure, Figure or Figure . Check continuity of specified wire between fuel pump relay harness connector and PCM harness connector terminal No. 8 (on Altima and Sentra), No. 11 (on Frontier, Pathfinder, Quest and QX4) or No. 117 (on Maxima). See FUEL PUMP RELAY CIRCUIT IDENTIFICATION  table. See Figure or Figure . If continuity exists, go to next step. If continuity does not exist, repair open in appropriate wire.
  7. 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.
  8. No problem is indicated at this time. Problem may be intermittent. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
FUEL PUMP RELAY CIRCUIT IDENTIFICATION

Application Circuit Terminal No. (Wire Color)
Altima Power Supply 1 (Black/Blue) & 3 (Black/White)
To PCM 2 (Black/Pink)
To Fuel Pump 5 (Black/Yellow)
Frontier Power Supply 2 & 5 (Black/White)
To PCM 1 (White/Red)
To Fuel Pump 3 (White/Blue)
Maxima Power Supply 1 (Brown) & 3 (Black/White)
To PCM 2 (Black/Pink)
To Fuel Pump 5 (Black/Yellow)
Pathfinder & QX4 Power Supply 2 & 3 (Black/Yellow)
To PCM 1 (Red/Blue)
To Fuel Pump 5 (White/Blue)
Quest Power Supply 1 & 3 (Black/Red)
To PCM 2 (Blue/Red)
To Fuel Pump 5 (Light Green/Red)
Sentra Power Supply 1 (Black/Blue) & 3 (Black/White)
To PCM 2 (Black/Pink)
To Fuel Pump 5 (Black/Yellow)
FUEL PUMP CIRCUIT IDENTIFICATION

Application Circuit Terminal No. (Wire Color)
Altima Power Supply + (Black/Yellow)
Ground - (Black)
Frontier (4-Cylinder) Power Supply P1 (White/Yellow)
Ground P2 (Black)
Frontier (V6), Pathfinder & QX4 Power Supply 1 (White/Blue)
Ground 2 (Black)
Maxima & Sentra (1.6L) Power Supply 1 (Black/Yellow)
Ground 2 (Black)
Quest Power Supply 2 (Light Green/Red)
Ground (1) 3 (Black/White)
Sentra (2.0L) Power Supply 1 (Light Blue)
Ground 2 (Black)
(1) Through inertia fuel shutoff switch.