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 sub-assembly) 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 sub-assembly) and main body ECU (multiplex network body ECU) for 10 seconds or more.
  • Sliding roof ECU (sliding roof drive gear sub-assembly)

  • Main body ECU (multiplex network body ECU)

  • Instrument panel junction block assembly

  • Wire harness or connector

  • S/ROOF fuse

WIRING DIAGRAM

A01VW70E73

CAUTION / NOTICE / HINT

Note


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

  • If the main body ECU (multiplex network body ECU) is replaced, refer to Service Bulletin.

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

    Click here

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

    Click here


    • *: w/o Canister Pump Module with Door Ajar Warning Function

PROCEDURE


  1. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.

      Click here

      A01VXVVC03
      *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
      2B-17 - MB-16 (LIN2) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

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


    1. Disconnect the U2 sliding roof ECU (sliding roof drive gear sub-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 engine switch from on (IG) to off and wait for 180 seconds or more without operating any switches.

      Standard Resistance
      Tester Connection Condition Specified Condition
      2B-17 -U2-7 (MPX1) Engine switch off Below 1 Ω
      U2-7 (MPX1) or 2B-17 - Body ground Engine switch off 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG
    OK
  3. 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
      U2-1 (B) - U2-2 (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
      U2-2 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG
    OK
  4. 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
  5. CHECK FOR DTC


    1. Clear the DTCs.

      Click here


      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
    NG