LIN COMMUNICATION SYSTEM, Diagnostic DTC:B1273

DTC Code DTC Name
B1273 Sliding Roof ECU Communication Stop

DESCRIPTION

This DTC is stored when LIN communication between the sliding roof ECU (sliding roof drive gear assembly)*1 or sliding roof ECU (sliding roof drive gear sub-assembly)*2 and main body ECU (multiplex network body ECU) stops for 10 seconds or more.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1273 Sliding Roof ECU Communication Stop No communication between sliding roof ECU (sliding roof drive gear assembly)*1 or sliding roof ECU (sliding roof drive gear sub-assembly)*2 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

  • Sliding roof ECU (sliding roof drive gear assembly)*1

  • Sliding roof ECU (sliding roof drive gear sub-assembly)*2

  • Wire harness or connector

  • S/ROOF fuse

WIRING DIAGRAM

B00866YE47
B00866YE48

CAUTION / NOTICE / HINT

Note


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

  • When the sliding roof ECU (sliding roof drive gear assembly) is replaced or removed and reinstalled, it is necessary to perform initialization.*1

    Click here

  • When the sliding roof ECU (sliding roof drive gear sub-assembly) is replaced or removed and reinstalled, it is necessary to perform initialization.*2

    See pageXXX

  • Before replacing the main body ECU (multiplex network body ECU), refer to Service Bulletin.*3

  • 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.*4

    Click here


    • *1: w/ Panoramic Moon Roof System

    • *2: w/ Sliding Roof System

    • *3: w/ Smart Entry and Start System

    • *4: w/ Door Control Battery

PROCEDURE


  1. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.

      Click here

      B008711C09
      *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
      3B-17 - MB-16 (LIN2) Always Below 1 Ω
      Result
      Result Proceed to
      OK (w/ Panoramic Moon Roof System) A
      OK (w/ Sliding Roof System) B
      NG C

    B

    CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)) Click here

    C

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    A

  2. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY))


    1. Disconnect the q1 sliding roof ECU (sliding roof drive gear assembly) connector.

    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
      Tester Connection Condition Specified Condition
      3B-17 - q1-7 (LIN) Ignition switch off Below 1 Ω
      3B-17 or q1-7 (LIN) - 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 (SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY) - BATTERY, BODY GROUND)


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

      Standard Voltage
      Tester Connection Condition Specified Condition
      q1-1 (+B) - q1-2 (E) Always 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      q1-2 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)


    1. Replace the sliding roof ECU (sliding roof drive gear 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 B1273 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY) WAS DEFECTIVE)

    NG

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

  6. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY))


    1. Disconnect the V19 sliding roof ECU (sliding roof drive gear sub-assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3B-17 - V19-7 (MPX1) Ignition switch off Below 1 Ω
      V19-7 (MPX1) or 3B-17 - Body ground Ignition switch off 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK HARNESS AND CONNECTOR (SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY) - BATTERY, BODY GROUND)


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

      Standard Voltage
      Tester Connection Condition Specified Condition
      V19-1 (B) - V19-2 (E) Always 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      V19-2 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)


    1. Replace the sliding roof ECU (sliding roof drive gear sub-assembly).

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  9. 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 B1273 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY) WAS DEFECTIVE)

    NG

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