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DTC B1206: P/W Master Switch Communication Stop: Procedure

  1. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Remove the instrument panel junction block assembly. Refer to REMOVAL [03/2012 - ] - Step 2 .
      GTY266017Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
    3. Measure the resistance according to the value(s) in the table below.

      HINT: 

      This inspection is to check the LIN line in the instrument panel junction block assembly that connects the wire harness to the built-in main body ECU (multiplex network body ECU).

      Standard Resistance

      Tester Connection Condition Specified Condition
      2D-27 (LIN2) - MB-16 (LIN2) Always Below 1 Ω
      2D-27 (LIN2) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Component without harness connected
      (Instrument Panel Junction Block Assembly)
      *2 Component without harness connected
      (Instrument Panel Junction Block Assembly)

    NG → See step   6 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the J7 connector.
      GTY357448Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2D-27 (LIN2) - J7-17 (LIN1) Always Below 1 Ω
      2D-27 (LIN2) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Instrument Panel Junction Block Assembly)
      *2 Front view of wire harness connector
      (to Multiplex Network Master Switch Assembly)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR 
    1. Measure the voltage according to the value(s) in the table below.
      GTY350872Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      2D-27 (LIN2) - J7-17 (LIN1) Always 11 to 14 V
      TEXT IN ILLUSTRATION

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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. REPLACE MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY 
    1. Replace the multiplex network master switch assembly. Refer to REMOVAL [03/2012 - ] .

    NEXT: Go to next step 

  5. CHECK DTC OUTPUT 
    1. Clear the DTC. Refer to DTC CHECK / CLEAR [03/2012 - ] .
    2. Recheck for DTCs.

      OK

      DTC B1206 is not output.

    NG → See step   7 

    OK → END (MULTIPLEX NETWORK MASTER SWITCH WAS DEFECTIVE) 

  6. REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [03/2012 - ] - Step 2 
  7. REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [03/2012 - ]