LIN COMMUNICATION SYSTEM, Diagnostic DTC:B1249

DTC Code DTC Name
B1249 Double Locking ECU Communication Stop

DESCRIPTION

The main body ECU (multiplex network body ECU) stores this DTC when communication with the double lock door control relay assembly is interrupted for 10 seconds or more.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1249 Double Locking ECU Communication Stop No communication between double lock door control relay assembly and main body ECU (multiplex network body ECU) for 10 seconds or more
  • Double lock door control relay assembly

  • Main body ECU (multiplex network body ECU)

  • Instrument panel junction block assembly

  • Wire harness or connector

  • ECU-B NO. 1 fuse

  • D/L NO. 2 fuse

WIRING DIAGRAM

A012G1OE15

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.

      Click here

      A012H9XC03
      *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
      3C-22 - MB-16 (LIN2) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG
    OK
  2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) - DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY)


    1. Disconnect the E107 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
      3C-22 - E107-9 (MPX1) Always Below 1 Ω
      E107-9 (MPX1) - Body ground Always 10 kΩ or higher
      3C-22 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY - BATTERY, BODY GROUND)


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

      Standard Voltage
      Tester Connection Condition Specified Condition
      E107-1 (+B) - E107-14 (GND) Always 11 to 14 V
      E107-7 (CPUB) - E107-14 (GND) 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
      E107-14 (GND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG
    OK
  4. REPLACE DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY


    1. Replace the double lock door control relay assembly .

      Click here

      Result
      Proceed to
      NEXT

    NEXT
  5. CHECK DTC OUTPUT


    1. Clear the DTCs.

      Click here


      Body Electrical > Main Body > Clear DTCs
    2. Recheck for DTCs.


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

    OK
    NG