LIN COMMUNICATION SYSTEM, Diagnostic DTC:B1249

DTC Code DTC Name
B1249 Double Locking ECU Communication Stop

DESCRIPTION

DTC B1249 is stored when communication between the double lock door control relay assembly and main body ECU (multiplex network body ECU) stops for more than 10 seconds.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1249 Double Locking ECU Communication Stop No communication from the double lock door control relay assembly for more than 10 seconds.

  • Double lock door control relay assembly

  • Main body ECU (multiplex network body ECU)

  • Instrument panel junction block assembly

  • Harness or connector

WIRING DIAGRAM

B0058MXE04

CAUTION / NOTICE / HINT

Note


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

    Connect the GTS to the vehicle, and turn a courtesy light 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.

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

  • As the door control battery is installed between the vehicle battery and main body ECU (multiplex network body ECU), first perform the inspections in On-Vehicle Inspection to confirm that there are no malfunctions in the power source circuit for the main body ECU (multiplex network body ECU) before performing this troubleshooting procedure.*

    *: w/ Door Control Battery

Tech Tips

DTC B2325 is output when the communication between all of the following components and main body ECU (multiplex network body ECU) stops.

Click here

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > Main Body > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs.

      Click here


      Body Electrical > Main Body > Trouble Codes
      Result
      Proceed to
      DTC B1249 is output
      DTC B1249 is not output

    DTC B1249 is not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC B1249 is output

  3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] - DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY)


    1. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

      for LHD:

      Click here

      for RHD:

      Click here

      Connect the instrument panel junction block assembly connectors.

    2. Disconnect the I129 double lock door control relay assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A-16 (LIN2) - I129-9 (MPX1) Always Below 1 Ω
      A-16 (LIN2) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY) Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY - BATTERY AND BODY GROUND)


    1. B005A1OC03
      *a

      Front view of wire harness connector

      (to Double Lock Door Control Relay Assembly)

      Disconnect the double lock door control relay assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I129-14 (GND) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      I129-1 (+B) - Body ground Always 11 to 14 V
      I129-7 (CPUB) - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. REPLACE DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY


    1. Temporarily replace the double lock door control relay assembly with a new or normally functioning one.

      Click here

    2. Clear the DTCs.

      Click here


      Body Electrical > Main Body > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK FOR DTC


    1. Check for DTCs.

      Click here


      Body Electrical > Main Body > Trouble Codes
      Result
      Proceed to
      DTC B1249 is not output
      DTC B1249 is output (for LHD)
      DTC B1249 is output (for RHD)

    DTC B1249 is not output

    END (DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY IS DEFECTIVE)

    DTC B1249 is output (for LHD)

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

    DTC B1249 is output (for RHD)

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

  7. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY)


    1. Disconnect the instrument panel junction block assembly.

    2. Disconnect the I129 double lock door control relay assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      4D-41 - I129-9 (MPX1) Always Below 1 Ω
      4D-41 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK (for LHD)
      OK (for RHD)
      NG

    OK (for LHD)

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    OK (for RHD)

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR