CAN COMMUNICATION SYSTEM (for LHD without Entry and Start System), Diagnostic DTC:U1114

DTC Code DTC Name
U1114 Lost Communication with Main Switch Module

DESCRIPTION

DTC Code DTC Detection Condition Trouble Area
U1114 There is no communication from the driving support switch control ECU.

  • Power source circuit of driving support switch control ECU

  • Driving support switch control ECU CAN branch wire or connector

  • Driving support switch control ECU

WIRING DIAGRAM

A01DQUJE03

INSPECTION PROCEDURE

Note

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

Tech Tips

Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

PROCEDURE


  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the CAN main wire and the CAN branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the airbag system.

      Note


      • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Click here.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.


    NEXT

  2. CHECK FOR OPEN IN CAN BUS WIRE (DRIVING SUPPORT SWITCH CONTROL ECU CAN BRANCH WIRE)


    1. for Automatic Transmission:


      1. A01DM6UE01
        Text in Illustration
        *a

        Front view of wire harness connector

        (to Driving Support Switch Control ECU)

        Disconnect the G163 driving support switch control ECU connector.

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

        Standard Resistance
        Tester Connection Switch Condition Specified Condition
        G163-2 (CANP) - G163-3 (CANN) Ignition switch off 54 to 69 Ω

    2. for Manual Transmission:


      1. A01DM3DE01
        Text in Illustration
        *a

        Rear view of wire harness connector

        (to Driving Support Switch Control ECU)

        Disconnect the G76 driving support switch control ECU connector.

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

        Standard Resistance
        Tester Connection Switch Condition Specified Condition
        G76-9 (CANP) - G76-10 (CANN) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE DRIVING SUPPORT SWITCH CONTROL ECU CAN BRANCH WIRE OR CONNECTOR (CANP, CANN)

    OK

  3. CHECK HARNESS AND CONNECTOR (DRIVING SUPPORT SWITCH CONTROL ECU - BATTERY AND BODY GROUND)


    1. Connect the cable to the negative (-) battery terminal.

      Note

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. for Automatic Transmission:


      1. A01DM6UE02
        Text in Illustration
        *a

        Front view of wire harness connector

        (to Driving Support Switch Control ECU)

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        G163-7 (GND) - Body ground Always Below 1 Ω

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

        Standard Voltage
        Tester Connection Condition Specified Condition
        G163-8 (+B) - Body ground Always 11 to 14 V
        G163-10 (IG) - Body ground Ignition switch ON 11 to 14 V

    3. for Manual Transmission:


      1. A01DM3DE02
        Text in Illustration
        *a

        Rear view of wire harness connector

        (to Driving Support Switch Control ECU)

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        G76-16 (GND) - Body ground Always Below 1 Ω

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

        Standard Voltage
        Tester Connection Condition Specified Condition
        G76-6 (+B) - Body ground Always 11 to 14 V
        G76-7 (IG) - Body ground Ignition switch ON 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE DRIVING SUPPORT SWITCH CONTROL ECU Click here