LIN COMMUNICATION SYSTEM, Diagnostic DTC:B1206

DTC Code DTC Name
B1206 P/W Master Switch Communication Stop

DESCRIPTION

This DTC is stored when LIN communication between the multiplex network master switch assembly and main body ECU (multiplex network body ECU) stops for 10 seconds or more.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1206 P/W Master Switch Communication Stop No communication between multiplex network master switch assembly and main body ECU (multiplex network body ECU) for 10 seconds or more.

  • Main body ECU (multiplex network body ECU)

  • Instrument panel junction block assembly

  • Multiplex network master switch assembly

  • Wire harness or connector

  • ECU-B NO. 2 fuse

WIRING DIAGRAM

B0071R9E08

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses for circuits related to this system before performing the following procedure.

  • Before replacing the main body ECU (multiplex network body ECU), refer to Service Bulletin.*


    • *: w/ Smart Entry and Start System

  • The vehicle battery supplies power to the main body ECU (multiplex network body ECU) via the door control battery. Therefore, before performing this troubleshooting procedure, make sure to perform an on-vehicle inspection to confirm that the main body ECU (multiplex network body ECU) power source circuit is normal.*

    Click here


    • *: w/ Door Control Battery

PROCEDURE


  1. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.

      Click here

      B004LF9C20
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -

    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.

      Tech Tips

      This inspection is to check the LIN communication 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
      3D-25 - MB-16 (LIN2) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY)


    1. Disconnect the O2*1 or N2*2 multiplex network master switch assembly connector.


      • *1: for LHD

      • *2: for RHD

    2. Measure the resistance according to the value(s) in the table below.

      Note

      Make sure that each ECU is in sleep mode before performing the inspection. To enter sleep mode, turn the ignition switch from ON to off and wait for 180 seconds or more without operating any switches.

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      3D-25 - O2-17 (LIN1) Ignition switch off Below 1 Ω
      3D-25 or O2-17 (LIN1) - Body ground Ignition switch off 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      3D-25 - N2-17 (LIN1) Ignition switch off Below 1 Ω
      3D-25 or N2-17 (LIN1) - Body ground Ignition switch off 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY - BATTERY, BODY GROUND)


    1. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      for LHD
      Tester Connection Condition Specified Condition
      O2-11 (B) - O2-12 (GND) Always 11 to 14 V
      for RHD
      Tester Connection Condition Specified Condition
      N2-11 (B) - N2-12 (GND) Always 11 to 14 V

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      O2-12 (GND) - Body ground Always Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      N2-12 (GND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY


    1. Replace the multiplex network master switch assembly.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  5. CHECK FOR DTC


    1. Clear the DTCs.


      Body Electrical > Main Body > Clear DTCs

    2. Recheck for DTCs.


      Body Electrical > Main Body > Trouble Codes
      OK
      DTC B1206 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY WAS DEFECTIVE)

    NG

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here