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DTC B1206: P/W Master Switch Communication Stop [09/2014 - ]: Procedure

  1. CLEAR DTC 
    1. Clear the DTCs (Refer to DTC CHECK / CLEAR [09/2014 - ] ).

    Result: 

    NEXT 

    See step  2

  2. CHECK FOR DTC 
    1. Check for DTCs (Refer to DTC CHECK / CLEAR [09/2014 - ] ).
      RESULT

      Result Proceed to
      DTC B1206 is output A
      DTC B1206 is not output B

    Result: 

    B 

    USE SIMULATION METHOD TO CHECK 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [09/2014 - 10/2015] or refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - ] )

    Result: 

    A 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] - MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY) 
    1. Remove the main body ECU (multiplex network body ECU) from the cowl side junction block LH (Refer to REMOVAL [09/2014 - ] ).
    2. Disconnect the Q25 multiplex network master switch assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A-16 (LIN2) - Q25-17 (LIN1) Always Below 1 Ω
      A-16 (LIN2) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (FRONT MULTIPLEX NETWORK DOOR ECU LH - BATTERY AND BODY GROUND) 
    GTY530603Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the front multiplex network door ECU LH connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      Q19-1 (GND) - 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
      Q19-6 (BDR) - Q19-1 (GND) Always 11 to 14 V
      Q19-16 (BCUT) - Q19-1 (GND) Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Front Multiplex Network Door ECU LH)

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (FRONT MULTIPLEX NETWORK DOOR ECU LH - MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY) 
    1. Disconnect the Q19 front multiplex network door ECU LH connector.
    2. Disconnect the Q25 multiplex network master switch assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      Q19-15 (CPBJ) - Q25-11 (B) Always Below 1 Ω
      Q19-9 (SGND) - Q25-12 (GND) Always Below 1 Ω
      Q19-15 (CPBJ) - Body ground Always 10 kΩ or higher
      Q19-9 (SGND) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK FRONT MULTIPLEX NETWORK DOOR ECU LH 
    GTY537804Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the multiplex network master switch assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      Q25-12 (GND) - 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
      Q25-11 (B) - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Multiplex Network Master Switch Assembly)

    Result: 

    NG 

    REPLACE FRONT MULTIPLEX NETWORK DOOR ECU LH 

    (Refer to DISASSEMBLY [09/2014 - ] )

    Result: 

    OK 

    See step  7

  7. REPLACE MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY 
    1. Temporarily replace the multiplex network master switch assembly with a new or normally functioning one (Refer to REMOVAL [09/2014 - ] ).
    2. Clear the DTC (Refer to DTC CHECK / CLEAR [09/2014 - ] ).

    Result: 

    NEXT 

    See step  8

  8. CHECK FOR DTC 
    1. Check for DTCs (Refer to DTC CHECK / CLEAR [09/2014 - ] ).

      OK

      DTC B1206 is not output.

    Result: 

    OK 

    END (MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY IS DEFECTIVE) 

    Result: 

    NG 

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) 

    (Refer to REMOVAL [09/2014 - ] )

  9. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] - FRONT MULTIPLEX NETWORK DOOR ECU LH) 
    1. Remove the main body ECU (multiplex network body ECU) from the cowl side junction block LH (Refer to REMOVAL [09/2014 - ] ).
    2. Disconnect the Q18 front multiplex network door ECU LH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A-16 (LIN2) - Q18-18 (LIN1) Always Below 1 Ω
      A-16 (LIN2) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (FRONT MULTIPLEX NETWORK DOOR ECU LH - MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY) 
    1. Disconnect the Q18 front multiplex network door ECU LH connector.
    2. Disconnect the Q25 multiplex network master switch assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      Q18-8 (LIN2) - Q25-17 (LIN1) Always Below 1 Ω
      Q18-8 (LIN2) - Body ground Always 10 kΩ or higher

    Result: 

    OK 

    REPLACE FRONT MULTIPLEX NETWORK DOOR ECU LH 

    (Refer to DISASSEMBLY [09/2014 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  11. CHECK HARNESS AND CONNECTOR (COWL SIDE JUNCTION BLOCK LH - FRONT MULTIPLEX NETWORK DOOR ECU LH) 
    1. Disconnect the 5C cowl side junction block LH connector.
    2. Disconnect the Q18 front multiplex network door ECU LH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      5C-28 - Q18-18 (LIN1) Always Below 1 Ω
      5C-28 - Body ground Always 10 kΩ or higher

    Result: 

    OK 

    REPLACE COWL SIDE JUNCTION BLOCK LH 

    (Refer to REMOVAL [09/2014 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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