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Home >> Infiniti >> 2012 >> G25 Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 17 (Security Control System) >> DTC/Circuit Diagnosis >> DTC B2603: Shift Position >> Diagnosis Procedure
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Diagnosis Procedure

WARNING: This page is about a different car, the 2011 Nissan Leaf. However, it is still accessible from the selected car via links, so may be relevant.
  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  5.

  2. CHECK DTC OF ELECTRIC SHIFT CONTOROL MODULE

    Check DTC in "Self Diagnostic Result" mode of "SHIFT" 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 P/N POSITION SIGNAL CIRCUIT
    1. Turn power switch OFF.
    2. Disconnect BCM connector.
    3. Disconnect electric shift control module connector.
    4. Check continuity between BCM harness connector and electric shift control module harness connector.
      CONTINUITY REFERENCE CHART

      BCM Electric shift control module Continuity
      Connector Terminal Connector Terminal
      M70 102 M58 13 Existed
    5. Check continuity between BCM harness connector and ground.
      CONTINUITY REFERENCE CHART

      BCM Ground Continuity
      Connector Terminal
      M70 102 Not existed

      Is the inspection result normal? 

      YES: Go to 4.

      NO: Repair or replace harness.

  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 DTC OF ELECTRIC SHIFT CONTOROL MODULE

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

    Is DTC detected? 

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

    NO: Go to 6.

  6. CHECK P POSITION SIGNAL CIRCUIT
    1. Turn power switch OFF.
    2. Disconnect BCM connector.
    3. Disconnect electric shift control module connector.
    4. Check continuity between BCM harness connector and electric shift control module harness connector.
      CONTINUITY REFERENCE CHART

      BCM Electric shift control module Continuity
      Connector Terminal Connector Terminal
      M68 37 M58 12 Existed
    5. Check continuity between BCM harness connector and ground.
      CONTINUITY REFERENCE CHART

      BCM Ground Continuity
      Connector Terminal
      M68 37 Not existed

      Is the inspection result normal? 

      YES: Go to 7.

      NO: Repair or replace harness.

  7. 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

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