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Home >> Infiniti >> 2012 >> M37 Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Security Control System (With Intelligent Key System) >> DTC/Circuit Diagnosis >> DTC B2603: Shift Position >> Diagnosis Procedure
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Diagnosis Procedure

  1. INSPECTION START 

    Perform inspection in accordance with the procedure that confirms DTC.

    Which procedure confirms DTC? 

    DTC confirmation procedure 1: GO TO 2.

    DTC confirmation procedure 2: GO TO  6.

  2. CHECK DTC OF TCM 

    Check DTC in "Self Diagnostic Result" mode of "TCM" using CONSULT.

    Is DTC detected? 

    YES: Perform the trouble diagnosis related to the detected DTC. Refer to "DTC INDEX ".

    NO: GO TO 3.

  3. CHECK BCM INPUT SIGNAL 
    1. Turn ignition switch ON.
    2. Check voltage between BCM harness connector and ground.
      (+) (-) Condition Voltage (V) (Approx.)
      BCM
      Connector Terminal
      M123 102 Ground Selector lever P or N position 12
      Other than above 0

      Is the inspection result normal? 

      YES: GO TO 4.

      NO: GO TO  5.

  4. REPLACE BCM 
    1. Replace BCM. Refer to "REMOVAL AND INSTALLATION ".
    2. Perform initialization of BCM and registration of all Intelligent Keys using CONSULT.

      : INSPECTION END

  5. CHECK BCM INPUT SIGNAL CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect BCM connector.
    3. Disconnect A/T assembly connector.
    4. Check continuity between A/T assembly harness connector and BCM harness connector.
      A/T assembly BCM Continuity
      Connector Terminal Connector Terminal
      F61 9 M123 102 Existed
    5. Check continuity between A/T assembly harness connector and ground.
      A/T assembly Ground Continuity
      Connector Terminal
      F61 9 Not existed

      Is the inspection result normal? 

      YES: GO TO  11.

      NO: Repair or replace harness.

  6. CHECK A/T SHIFT SELECTOR POWER SUPPLY 
    1. Turn ignition switch OFF.
    2. Disconnect A/T shift selector (detention switch) connector.
    3. Check voltage between A/T shift selector (detention switch) harness connector and ground.
      (+) (-) Voltage (V) (Approx.)
      A/T shift selector (detention switch)
      Connector Terminal
      M137 7 Ground 12

      Is the inspection result normal? 

      YES: GO TO  9.

      NO: GO TO 7.

  7. CHECK A/T SHIFT SELECTOR POWER SUPPLY CIRCUIT 
    1. Disconnect BCM connector.
    2. Check continuity between A/T shift selector (detention switch) harness connector and BCM harness connector.
      A/T shift selector (detention switch) BCM Continuity
      Connector Terminal Connector Terminal
      M137 7 M123 104 Existed
    3. Check continuity between A/T shift selector (detention switch) harness connector and ground.
      A/T shift selector (detention switch) Ground Continuity
      Connector Terminal
      M137 7 Not existed

      Is the inspection result normal? 

      YES: GO TO 8.

      NO: Repair or replace harness.

  8. REPLACE BCM 
    1. Replace BCM. Refer to "REMOVAL AND INSTALLATION ".
    2. Perform initialization of BCM and registration of all Intelligent Keys using CONSULT.

      : INSPECTION END

  9. CHECK A/T SHIFT SELECTOR CIRCUIT 
    1. Disconnect BCM connector and IPDM E/R connector.
    2. Check continuity between A/T shift selector (detention switch) harness connector and BCM harness connector.
      A/T shift selector (detention switch) BCM Continuity
      Connector Terminal Connector Terminal
      M137 8 M120 37 Existed
    3. Check continuity between A/T shift selector (detention switch) harness connector and ground.
      A/T shift selector (detention switch) Ground Continuity
      Connector Terminal
      M137 8 Not existed

      Is the inspection result normal? 

      YES: GO TO 10.

      NO: Repair or replace harness.

  10. CHECK A/T SHIFT SELECTOR (DETENTION SWITCH) 

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 11.

    NO: Replace A/T shift selector. Refer to "2WD: REMOVAL AND INSTALLATION " (2WD) or "AWD: REMOVAL AND INSTALLATION " (AWD).

  11. CHECK INTERMITTENT INCIDENT 

    Refer to "INTERMITTENT INCIDENT ".

    : INSPECTION END

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