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DTC B156C: Extension Module Disconnected [08/2015 - 08/2019]: Procedure

  1. CHECK FOR DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [08/2015 - 08/2017] , or refer to DTC CHECK / CLEAR [08/2017 - 08/2019]

    2. Turn the ignition switch off.
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2015 - 08/2017] , or refer to DTC CHECK / CLEAR [08/2017 - 08/2019]

      OK

      No DTCs are output.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2017]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2017 - 08/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2018 - 08/2019] 

    Result: 

    NG 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER ASSEMBLY - STEREO REPLACEMENT COMPONENT TUNER ASSEMBLY) 
    1. Disconnect the e1 navigation receiver assembly connectors.
    2. Disconnect the e3 stereo replacement component tuner assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      e1-4 (+B2) - e3-4 (+B2) Always Below 1 Ω
      e1-3 (ACC2) - e3-3 (ACC2) Always Below 1 Ω
      e1-8 (GND2) - e3-8 (GND2) Always Below 1 Ω
      e1-4 (+B2) - Body ground Always 10 kΩ or higher
      e1-3 (ACC2) - Body ground Always 10 kΩ or higher
      e1-8 (GND2) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. INSPECT NAVIGATION RECEIVER ASSEMBLY 
    1. Disconnect the stereo replacement component tuner assembly connector.
      GTY928278Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Stereo Replacement Component Tuner Assembly)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      e3-4 (+B2) - e3-8 (GND2) Always 11 to 14 V
      e3-3 (ACC2) - e3-8 (GND2) Ignition switch ACC 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE NAVIGATION RECEIVER ASSEMBLY. Refer to  REMOVAL [08/2015 - 08/2019] 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (USB COMMUNICATION LINE) 
    1. Disconnect the f1 navigation receiver assembly connectors.
      GTY931261Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Navigation Receiver Assembly)
      *a Front view of wire harness connector
      (to Stereo replacement component Tuner Assembly)
    2. Disconnect the f2 stereo replacement component tuner assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      f1-1 (USV4) - f2-1 (USV4) Always Below 1 Ω
      f1-2 (US4-) - f2-2 (US4-) Always Below 1 Ω
      f1-3 (US4+) - f2-3 (US4+) Always Below 1 Ω
      f1-4 (UGD4) - f2-4 (UGD4) Always Below 1 Ω
      f1-5 (USG4) - f2-5 (USG4) Always Below 1 Ω
      f1-1 (USV4) - Body ground Always 10 kΩ or higher
      f1-2 (US4-) - Body ground Always 10 kΩ or higher
      f1-3 (US4+) - Body ground Always 10 kΩ or higher
      f1-4 (UGD4) - Body ground Always 10 kΩ or higher
      f1-5 (USG4) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK STEREO REPLACEMENT COMPONENT AMPLIFIER ASSEMBLY 
    1. Replace the stereo component tuner assembly with a known good one.

      Refer to REMOVAL [08/2015 - 08/2019]

    2. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [08/2015 - 08/2017] , or refer to DTC CHECK / CLEAR [08/2017 - 08/2019]

    3. Turn the ignition switch off.
    4. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2015 - 08/2017] , or refer to DTC CHECK / CLEAR [08/2017 - 08/2019]

      OK

      No DTCs are output.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (STEREO REPLACEMENT COMPONENT TUNER ASSEMBLY IS DEFECTIVE) 

    Result: 

    NG 

    REPLACE NAVIGATION RECEIVER ASSEMBLY. Refer to  REMOVAL [08/2015 - 08/2019]