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 and main body ECU (multiplex network body ECU) stops for 10 seconds or more.

DTC Code DTC Detection Condition Trouble Area
B1273 No communication between the sliding roof ECU and main body ECU (multiplex network body ECU) for 10 seconds or more.

  • Sliding roof driver gear sub-assembly (Sliding roof ECU)

  • Main body ECU (multiplex network body ECU)

  • Cowl side junction block LH

  • Harness or connector

WIRING DIAGRAM

A01X4ZME03

CAUTION / NOTICE / HINT

Note


  • When using the GTS with the ignition switch off to troubleshoot:

    Connect the GTS to the vehicle, and turn a courtesy switch on and off at 1.5 second intervals until communication between the GTS and vehicle begins.

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

Tech Tips

DTC B2325 is stored when the communication between the sliding roof ECU and main body ECU (multiplex network body ECU) stops.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTC Click here.


    NEXT

  2. CHECK FOR DTC


    1. Recheck for DTCs Click here.

      Result
      Result Proceed to
      DTC B1273 is output A
      DTC B1273 is not output B

    B

    USE SIMULATION METHOD TO CHECK Click here

    A

  3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] - SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)


    1. Disconnect the A main body ECU connector.

    2. Disconnect the R18 sliding roof ECU connector.

    3. Measure the resistance according to the value(s) in the tables below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A-16 (LIN2) - R18-11 (MPX1) Always Below 1 Ω
      A-16 (LIN2) or R18-11 (MPX1) - Body ground Always 10 kΩ or higher

    NG

    CHECK HARNESS AND CONNECTOR (COWL SIDE JUNCTION BLOCK LH - SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY) Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY BATTERY AND BODY GROUND


    1. A01XBIWE01

      Disconnect the R18 sliding roof ECU connector.

    2. Measure the resistance and voltage according to the value(s) in the tables below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      R18-12 (E) - Body ground Always Below 1 Ω
      Standard Voltage
      Tester Connection Condition Specified Condition
      R18-8 (B) - Body ground Always 11 to 14 V
      R18-1 (IG) - Body ground Ignition switch ON 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Temporarily replace the sliding roof ECU with a new or normally functioning one Click here.

    2. Clear the DTC Click here.


    NEXT

  6. CHECK FOR DTC


    1. Recheck for DTCs Click here.

      Result
      Result Proceed to
      DTC B1273 is not output A
      DTC B1273 is output (for LHD) B
      DTC B1273 is output (for RHD) C

    A

    END (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY [SLIDING ROOF ECU]) IS DEFECTIVE

    B

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

    C

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

  7. CHECK HARNESS AND CONNECTOR (COWL SIDE JUNCTION BLOCK LH - SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)


    1. Disconnect the 2J cowl side junction block LH connector.

    2. Disconnect the R18 sliding roof ECU connector.

    3. Measure the resistance according to the value(s) in the tables below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      2J-13 - R18-11 (MPX1) Always Below 1 Ω
      2J-13 or R18-11 (MPX1) - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    A

    REPLACE COWL SIDE JUNCTION BLOCK LH Click here

    B

    REPLACE COWL SIDE JUNCTION BLOCK LH Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR