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Home >> Infiniti >> 2004 >> QX56 AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System >> DTC P1706: PNP Switch >> Diagnostic Procedure
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Diagnostic Procedure

  1. CHECK DTC WITH TCM 

    Refer to OBD-II DIAGNOSTIC TROUBLE CODE (DTC) .

    OK or NG

    OK: GO TO 2.

    NG: Repair or replace.

  2. CHECK STARTING SYSTEM 

    Turn ignition switch OFF, then turn it to START.

    Does starter motor operate? 

    Yes or No

    Yes: GO TO 3.

    No: Refer to STARTING SYSTEM .

  3. CHECK PNP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-I 
    1. Turn ignition switch OFF.
    2. Disconnect TCM harness connector.
    3. Disconnect combination meter harness connector.
    4. Check harness continuity between TCM terminal 9 and combination meter terminal 39. Refer to Wiring Diagram.

      Continuity should exist. 

    5. Also check harness for short to ground and short to power.

    OK or NG

    OK: GO TO  5.

    NG: GO TO 4.

  4. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors F14, E5
    • Harness connectors E152, M31
    • Harness for open or short between TCM and combination meter

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

  5. CHECK PNP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminal 102 and combination meter terminal 40. Refer to Wiring Diagram.

      Continuity should exist. 

    3. Also check harness for short to ground and short to power.

    OK or NG

    OK: GO TO  7.

    NG: GO TO 6.

  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M31, E152
    • Harness for open or short between ECM and combination meter

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

  7. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

    OK or NG

    OK: GO TO 8.

    NG: Repair or replace.

  8. REPLACE COMBINATION METER 

    Refer to COMBINATION METERS .

    : INSPECTION END