LIN COMMUNICATION SYSTEM, Diagnostic DTC:B1273

DTC Code DTC Name
B1273 Sliding Roof ECU Communication Stop

DESCRIPTION

This DTC is output when LIN communication between the sliding roof drive gear and main body ECU stops for 10 seconds or more.

DTC Code DTC Detection Condition Trouble Area
B1273 No communication between sliding roof drive gear and main body ECU for 10 seconds or more

  • Sliding roof drive gear sub-assembly

  • Main body ECU

  • Wire harness

WIRING DIAGRAM

A01GN78E01

INSPECTION PROCEDURE

Note


  • When using the intelligent tester with the engine switch off to troubleshoot:

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

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

Tech Tips

DTC B2325 is output when the communication between all of the following components and main body ECU (driver side junction block) stops.

PROCEDURE


  1. CLEAR DTC


    1. Delete the DTC Click here.


    NEXT

  2. CHECK FOR DTC


    1. Recheck for DTC Click here.

      Result:
      Result Proceed to
      DTC B1273 output reoccurs A
      DTC B1273 output does not reoccur B

    B

    USE SIMULATION METHOD TO CHECK Click here

    A

  3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - SLIDING ROOF DRIVE GEAR)

    A01GKU7E02

    1. Disconnect the L11 ECU connector.

    2. Disconnect the X5 gear connector.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      L11-10 (LIN2) - X5-4 (MPX1) Always Below 1 Ω
      L11-10 (LIN2) or X5-4 (MPX1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY (BATTERY VOLTAGE AND GROUND)


    1. A01GLC3E04

      Disconnect the X5 gear connector.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      X5-2 (E) - Body ground Always Below 1 Ω
      Standard voltage
      Tester Connection Condition Specified Condition
      X5-1 (B) - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. REPLACE SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY


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


    NEXT

  6. CHECK FOR DTC


    1. Delete the DTC Click here.

    2. Recheck for DTC Click here.

      Result:
      Result Proceed to
      DTC B1273 output does not reoccur A
      DTC B1273 output reoccurs B

    B

    REPLACE MAIN BODY ECU

    A

    END (SLIDING ROOF DRIVE GEAR IS DEFECTIVE)