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Home >> Nissan-Datsun >> 2003 >> Sentra SE-R, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System & Component Testing >> Fuel System >> Fuel Control >> Fuel Injector Circuits (Altima 2.5L & Sentra 2.5L)
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Fuel Injector Circuits (Altima 2.5L & Sentra 2.5L)

  1. Start engine. If engine starts and CONSULT-II is available, go to next step. If engine starts and CONSULT-II is not available, go to step  3. If engine does not start, go to step  4.
  2. Start engine. Using CONSULT-II in ACTIVE TEST mode, perform POWER BALANCE test. Each cylinder should drop off when tested. If engine performs as specified, go to step  8. If engined does not perform as specified, go to step  4.
  3. Start engine and listen to each fuel injector. If every injector clicks, system is okay. If any injector does not click, go to next step
  4. Turn ignition off. Disconnect suspect fuel injector 2-pin harness connector. Turn ignition on. Measure voltage between ground and injector harness connector terminal No. 1 (Pink wire). See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. If battery voltage does not exist, go to next step. If battery voltage exists, go to step  6.
  5. For Sentra, check the following:
    • Check for poor, loose, corroded or damaged terminal connections at in-line harness connectors E108 and M19. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
    • Check for poor, loose, corroded or damaged terminal connections at in-line harness connectors E10 and F48.
    • Check for poor, loose, corroded or damaged terminal connections at in-line harness connectors F12 and F101.
    • Check for poor, loose, corroded or damaged terminal connections in fuse block harness connector M1.
    • Check fuse block fuse No. 17 (10-amp).
    • Check for open or short between suspect fuel injector and fuse.

    For Altima, check the following:

    • Check for poor, loose, corroded or damaged terminal connections at in-line harness connectors F59 and M71. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
    • Check for poor, loose, corroded or damaged terminal connections at in-line harness connectors F12 and F101.
    • Check for poor, loose, corroded or damaged terminal connections in fuse block harness connector M4.
    • Check fuse block fuse No. 1 (10-amp).
    • Check for open or short between suspect fuel injector and fuse.
    If problem is found, repair as necessary. After repair, retest system.

  6. Turn ignition off. Disconnect ECM 116-pin harness connector. See Figure or Figure . Check continuity of specified wire between fuel injector harness connector terminal No. 2 and ECM. See FUEL INJECTOR CIRCUIT IDENTIFICATION (ALTIMA 2.5L & SENTRA 2.5L)  table. See Figure. Also, check circuit for short to ground and short to voltage. If problem is found, go to next step. If no problem is found, go to step  8.
    FUEL INJECTOR CIRCUIT IDENTIFICATION (ALTIMA 2.5L & SENTRA 2.5L)

    Injector No. Wire Color At Injector Terminal No. 2 ECM Terminal No. Wire Color At ECM
    1 White 101 Red/Black
    2 Red/White 102 Red/White
    3 Green/Black 103 Red/Yellow
    4 Blue 104 Red/Blue
  7. Check the following:
    • Check for poor, loose, corroded or damaged terminal connections at in-line harness connectors F12 and F101. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
    • Check for open or short between suspect fuel injector and ECM.
  8. Check fuel injector. See FUEL INJECTOR . If problem is found, replace as necessary. If no problem is indicated at this time, go to next step.
  9. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
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