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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 wiring 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. On Maxima, disconnect dropping resistor harness connector located in trunk. See Fig 1. On Quest, disconnect fuel pump and fuel temperature sensor harness connector located behind fuel tank. See Fig 2. On all models, 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.
    Fig 1: Locating Fuel Pump Control Module (FPCM) & Dropping Resistor (Maxima)
    G99J54824Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 2: Locating Fuel Pump & Fuel Tank Temperature Sensor (FTTS) Harness Connector (Quest)
    G00015119Courtesy of NISSAN MOTOR CO., U.S.A.
  5. On Maxima, check continuity of fuel pump power supply wires between fuel pump harness connector terminal No. 2 and body ground, and between fuel pump harness connector terminal No. 1 and fuel pump relay harness connector terminal No. 3. On all other models, 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. Check continuity of specified wire between fuel pump relay harness connector and PCM harness connector terminal No. 6 (Altima), No. 11 (Frontier, Pathfinder, Quest and Xterra), No. 28 (Maxima), No. 20 (Sentra without engine immobilizer system) or No. 21 (Sentra with engine immobilizer system). See FUEL PUMP RELAY CIRCUIT IDENTIFICATION  table. See Figure, Figure, Figure, Figure, Figure and 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  under 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 & Xterra Power Supply 2 & 5 (Black/White)
To PCM 1 (White/Red)
To Fuel Pump 3 (White/Blue)
Maxima Power Supply 1 (Black/Red) & 5 (Black/White)
To PCM 2 (Black/Pink)
To Fuel Pump Control Module & Fuel Pump 3 (Black/Yellow)
Pathfinder 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/Red) & 5 (Black/White)
To PCM 2 (Black/Pink)
To Fuel Pump 3 (Black/Yellow)
FUEL PUMP CIRCUIT IDENTIFICATION

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