2003 Infiniti FX45FACTORY OEM SERVICE PROCEDURE

Fuel Injector Circuits (M45)

  1. Turn ignition switch to START position. If any cylinder ignites, go to next step. If no cylinder(s) ignites, go to step  3.
    • With CONSULT-II  - Perform POWER BALANCE in ACTIVE TEST mode with CONSULT-II. If each circuit produces a momentary engine speed drop, system is okay. If any circuit does not produce a momentary engine speed drop, go to next step.
    • Without CONSULT-II  - Start engine. Using appropriate listening device, listen to each injector. Audible clicking sound should be heard. If clicking sound is heard, system is okay. If clicking sound is not heard, go to next step.
  3. Turn ignition switch to OFF position. Disconnect injector sub-harness connector F21 and F201 (for left bank) or F41 and F221 (for right bank). Check voltage between ground and connector F21 terminal No. 5. Also check voltage between ground and connectors F41 terminal No. 5. Battery voltage should exist. If voltage is not as specified, go to next step. If voltage is as specified, go to step  5.
  4. Check the following:
    • Harness connectors E33 and F33.
    • Harness connectors F21 and F201.
    • Harness connectors F41 and F221.
    • Joint connector-19.
    • Fuse Block (J/B) No. 1 connector M1.
    • Fuse Block (J/B) No. 2 connectors M143 and E215.
    • 15-amp fuse.
    • Harness for open or short between harness connector F21 and fuse.
    • Harness for open or short between harness connector F41 and fuse.

    Repair open circuit or short to ground or short to power in harness or connectors.

  5. Turn ignition switch to OFF position. Disconnect ECM harness connector. Check continuity between specified terminals. Continuity should exist. Also check harness for open, short to ground and short to power. See TESTING INJECTOR OUTPUT SIGNAL CIRCUITS  table. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. If no problem is found, go to next step. If problem is found, repair or replace as required.
    TESTING INJECTOR OUTPUT SIGNAL CIRCUITS

    Harness Connector Terminal No. ECM Terminal No.
    F21 3 5
    - 2 7
    - 1 14
    - 6 16
    F41 3 6
    - 2 13
    - 1 15
    - 6 17
  6. Disconnect injector harness connectors. Check continuity between indicated harness connectors See TESTING INJECTOR CIRCUIT CONTINUITY  table. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Continuity should exist. If continuity exists, go to next step. If continuity does not exist, repair wiring or connectors as necessary.
    TESTING INJECTOR CIRCUIT CONTINUITY

    Harness Connector Terminal No. Terminal No.
    F21 5 1
    - 1, 2, 3 & 6 2
    F41 5 1
    - 1, 2, 3 & 6 2
  7. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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