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DTC B156C: Extension Module Disconnected: Procedure

  1. CHECK OPTIONAL COMPONENTS (INCLUDING ASSOCIATED WIRING) 
    1. Check for optional components.
      1. Check that optional components (including associated wiring) which generate radio waves are not installed.

        Result

        Result Proceed to
        Optional components (including associated wiring) are installed. A
        Optional components (including associated wiring) are not installed. B

        HINT: 

        • Electrical noise from radio waves generated by optional components or the wiring for those components may affect AVC-LAN communication.
        • This DTC may be stored when an AVC-LAN communication error occurs due to electrical noise.

    B → See step   3 

    A: Go to next step 

  2. REMOVE OPTIONAL COMPONENTS (INCLUDING ASSOCIATED WIRING) 
    1. Remove optional components (including associated wiring).
      NOTE:

      Do not remove optional components or associated wiring without the permission of the customer.

    NEXT: Go to next step 

  3. CHECK DTC 
    1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    2. Recheck for DTCs and check if the same DTC is output again.

      OK

      No DTCs are output.

    NG → See step   4 

    OK → END 

  4. CHECK HARNESS AND CONNECTOR (EXTENSION MODULE POWER SOURCE) 
    1. Disconnect the extension module connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      f1-32 (E) - Body ground Always Below 1 Ω
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      f1-16 (B+) - f1-32 (E) Always 11 to 14 V
      f1-11 (ACC) - f1-32 (E) Ignition switch ACC 11 to 14 V

    NG → See step   7 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - EXTENSION MODULE) 
    1. Disconnect the radio and display receiver assembly connector.
    2. Disconnect the extension module connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      f1-2 (AVC+) - f3-9 (AVC+) Always Below 1 Ω
      f1-3 (AVC-) - f3-10 (AVC-) Always Below 1 Ω
      f1-2 (AVC+) - Body ground Always 10 kΩ or higher
      f1-3 (AVC-) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. REPLACE EXTENSION MODULE 
    1. Replace the extension module. Refer to REMOVAL .
    2. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    3. Recheck for DTCs and check if the same DTC is output again.

      OK

      No DTCs are output.

    NG → See step   8 

    OK → END 

  7. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - EXTENSION MODULE) 
    1. Disconnect the radio and display receiver assembly connector.
    2. Disconnect the extension module connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      f1-11 (ACC) - f2-13 (ACC) Always Below 1 Ω
      f1-16 (B+) - f2-1 (B+) Always Below 1 Ω
      f1-32 (E) - f2-14 (E) Always Below 1 Ω
      f1-11 (ACC) - Body ground Always 10 kΩ or higher
      f1-16 (B+) - Body ground Always 10 kΩ or higher
      f1-32 (E) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   8 

  8. REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY. Refer to  REMOVAL