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Home >> Infiniti >> 2009 >> G37 Base, 4D Sedan >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 32 (Security Control System -- Convertible) >> DTC/Circuit Diagnosis >> DTC B2603: Shift Position Status >> Diagnosis Procedure
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Diagnosis Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK DTC WITH TCM

    Check "Self diagnosis result" with CONSULT-III.

    Are any DTC detected? 

    YES: Refer to "DTC INDEX ".

    NO: GO TO 2.

  2. CHECK TRANSMISSION RANGE SWITCH CIRCUIT 1
    1. Turn ignition switch OFF.
    2. Disconnect A/T assembly connector and BCM connector.
    3. Check continuity between A/T assembly harness connector and BCM harness connector.
      CONTINUITY CHART

      A/T assembly BCM Continuity
      Connector Terminal Connector Terminal
      F51 9 M123 140 Existed
    4. Check continuity between A/T assembly harness connector and ground.
      CONTINUITY CHART

      A/T assembly Ground Continuity
      Connector Terminal
      F51 9 Not existed

      Is the inspection result normal? 

      YES: GO TO 3.

      NO: Repair or replace harness.

  3. CHECK TRANSMISSION RANGE SWITCH CIRCUIT 2
    1. Disconnect TCM connector.
    2. Check continuity between TCM harness connector and A/T assembly harness connector.
      CONTINUITY CHART

      TCM A/T assembly Continuity
      Connector Terminal Connector Terminal
      F157 9 F51 9 Existed
    3. Check continuity between TCM harness connector and ground.
      CONTINUITY CHART

      TCM Ground Continuity
      Connector Terminal
      F157 9 Not existed

      Is the inspection result normal? 

      YES: GO TO 4.

      NO: Repair or replace harness.

  4. CHECK A/T SHIFT SELECTOR POWER SUPPLY
    1. Disconnect A/T shift selector (detention switch) connector.
    2. Check voltage between A/T shift selector (detention switch) harness connector and ground.
      VOLTAGE SPECIFICATION

      (+) (-) Voltage (V) (Approx.)
      A/T shift selector (detention switch)
      Connector Terminal
      M137 10 Ground Battery voltage

      Is the inspection result normal? 

      YES: GO TO  6.

      NO: GO TO 5.

  5. 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.
      CONTINUITY CHART

      A/T shift selector (detention switch) BCM Continuity
      Connector Terminal Connector Terminal
      M137 10 M122 96 Existed
    3. Check continuity between A/T shift selector (detention switch) harness connector and ground.
      CONTINUITY CHART

      A/T shift selector (detention switch) Ground Continuity
      Connector Terminal
      M137 10 Not existed

      Is the inspection result normal? 

      YES: Replace BCM. Refer to "REMOVAL AND INSTALLATION ".

      NO: Repair or replace harness.

  6. 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.
      CONTINUITY CHART

      A/T shift selector (detention switch) BCM Continuity
      Connector Terminal Connector Terminal
      M137 11 M122 99 Existed
    3. Check continuity between A/T shift selector (detention switch) harness connector and ground.
      CONTINUITY CHART

      A/T shift selector (detention switch) Ground Continuity
      Connector Terminal
      M137 11 Not existed

      Is the inspection result normal? 

      YES: GO TO 7.

      NO: Repair or replace harness.

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

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 8.

    NO: Replace A/T shift selector. Refer to "REMOVAL AND INSTALLATION ".

  8. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    INSPECTION END

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