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Home >> Nissan-Datsun >> 1993 >> Sentra SE-R, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Fuel System >> Fuel Delivery >> Fuel Pump System Test (Quest)
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Fuel Pump System Test (Quest)

  1. If engine cranks but does not start, check inertia switch. Inertia switch is located behind driver's kick panel and is accessible through hole in kick panel. If gasoline smell is present, locate and repair cause of smell before resetting inertia switch.
  2. Turn ignition on. With fingers, pinch fuel feed hose at fuel filter. Fuel pressure pulsation should be felt for 5 seconds after ignition is turned on. If pulsation is not felt, go to next step. If pulsation is felt, system is functioning properly.
  3. Turn ignition off. Disconnect fuel pump relay. Fuel pump relay is located in relay box in front of battery. Turn ignition on. Measure voltage between ground and fuel pump relay harness connector terminals No. 1 (Black/Red wire) and No. 3 (Black/Red wire). For connector identification, See Figure . Battery voltage should be present. If battery voltage is present, go to next step. If battery voltage is not present, check 15-amp fuse in main fuse box. Check harness continuity between fuse and fuel pump relay. Repair or replace as necessary.
  4. Turn ignition off. Disconnect fuel pump harness connector, located next to spare tire. Check continuity between ground and fuel pump harness connector Black/White wire. Check continuity between fuel pump relay harness connector terminal No. 5 (Light Green/Red wire) and fuel pump harness connector Light Green/Red wire. Continuity should exist in both checks. If continuity exists in both checks, go to next step. If continuity does not exist in either check, repair appropriate harness or connectors.
  5. Ensure ignition is off. Disconnect ECM harness connector. ECM is located behind glove box. Check continuity between ECM harness connector terminal No. 104 (Blue/Red wire) and fuel pump relay harness connector terminal No. 2 (Blue/Red wire). For terminal identification, see Figure , Figure and Figure . Continuity should exist. If continuity exists, check fuel pump relay. See RELAYS  under RELAYS & SOLENOIDS. If relay is okay, check fuel pump. See FUEL PUMP TEST. If continuity does not exist, check harness between ECM and relay. Repair harness and connectors as necessary.
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