MULTIPLEX COMMUNICATION SYSTEM, Diagnostic DTC:B1296

DTC Code DTC Name
B1296 Front Light ECU Communication Stop

DESCRIPTION

This DTC is detected if communication between the front controller and gateway ECU stops for more than 10 seconds.

DTC No. DTC Detection Condition Trouble Area
B1296 Front controller communication stops

  • Front controller

  • Wire harness or connector

WIRING DIAGRAM

A01621JE04

INSPECTION PROCEDURE

Tech Tips

If "+B of GND short malfunction of communication bus" DTCs (B1214 and B1215) are detected at the same time as "communication stop" DTC B1296, repair the "+B or GND short malfunction of communication bus" DTCs first Click here.

PROCEDURE


  1. INSPECT FUSE (MPX-B)


    1. Remove the MPX-B fuse from the engine room relay block No. 1.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      MPX-B fuse Always Below 1 Ω

    NG

    REPLACE FUSE

    OK

  2. CHECK HARNESS AND CONNECTOR (FRONT CONTROLLER - BATTERY AND BODY GROUND)


    1. A015YY3E06

      Disconnect the 2E and 2F ECU connectors.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      2E-4 (FMB3) - Body ground Always 11 to 14 V
      Standard Resistance
      Tester Connection Condition Specified Condition
      2F-1 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (FRONT CONTROLLER - BATTERY AND BODY GROUND)

    OK

  3. CHECK HARNESS AND CONNECTOR (COMMUNICATION LINE)


    1. A0162E3E07

      Disconnect the 2F, A30 and J55 ECU connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2F-6 (MPX2) - A30-17 (MPX2) Always Below 1 Ω
      2F-5 (MPX1) - J55-24 (MPX2) Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (COMMUNICATION LINE)

    OK

    REPLACE FRONT CONTROLLER