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Home >> Infiniti >> 2008 >> M45 Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (VK45DE) - DTCS P0460 Through P1421 >> DTC P0850 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 A/T assembly harness connector.
    3. Disconnect "unified meter and A/C amp." harness connector.
    4. Check harness continuity between A/T assembly terminal 9 and "unified meter and A/C amp." terminal 2. 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 M72, F102
    • Harness for open or short between A/T assembly and "unified meter and A/C amp."

      >> 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 "unified meter and A/C amp." terminal 21.

      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  6.

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

  6. CHECK PNP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-III 
    1. Check harness continuity between A/T assembly terminal 9 and TCM terminal 8.

      Refer to "DTC P0615 START SIGNAL CIRCUIT ".

      Continuity should exist. 

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

    OK or NG 

    OK: GO TO  7.

    NG: 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 "UNIFIED METER AND A/C AMP." 

    Refer to "UNIFIED METER AND A/C AMP ".

    >> INSPECTION END 

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