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Altima (3.5L)

  1. If CONSULT-II is available, go to next step. If CONSULT-II is not available, go to step  3.
  2. Using CONSULT-II in DATA MONITOR mode, observe START SIGNAL under following conditions. See CHECKING START SIGNAL (ALTIMA 3.5L)  table. If start signal displays as specified, go to step  8. If start signal does not display as specified, go to step  4.
    CHECKING START SIGNAL (ALTIMA 3.5L)

    Condition Start Signal
    Ignition Switch ON OFF
    Ignition Switch START ON
  3. Backprobing at ECM, measure voltage between ground and ECM terminal No. 42 (Brown/White wire) while cranking engine. See Figure. Battery voltage should exist when ignition switch is in START position. Voltage should be zero volts when ignition switch is in any other position except START. If voltage is as specified, go to step  8. If voltage is not as specified, go to next step.
  4. Turn ignition switch to OFF position, then to START position. If starter motor operates, go to next step. If starter motor does not operate, repair starting system. See appropriate STARTERS article in ELECTRICAL.
  5. Turn ignition switch off. Disconnect fuse block fuse No. 9 (10-amp). If fuse is okay, go to next step. If fuse is blown, replace and retest system.
  6. Turn ignition off. Disconnect ECM 116-pin harness connector. For ECM location, see Figure or Figure . Disconnect ignition switch harness connector. Check continuity in Brown/White wire between ECM harness connector terminal No. 42 and ignition switch harness connector terminal "R". See Figure. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Also, check circuit for short to ground or short to voltage. If problem is found, go to next step. If no problem is found, go to step  8.
  7. Check the following:
    • Check for poor, loose, corroded or damaged terminal connections at in-line harness connectors M71 and F59. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
    • Check for poor, loose, corroded or damaged terminal connections in fuse block harness connectors E30 and M3.
    • Check for open or short in Black/Yellow wire between ignition switch and fuse block.
    • Check for open or short in Brown/White wire between ECM and fuse block.
    If problem is found, repair as necessary. After repair, retest system.
  8. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.