CAN COMMUNICATION SYSTEM (for LHD with 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 branch wire or connector

  • Driving support switch control ECU

WIRING DIAGRAM

A00KWS3E44

INSPECTION PROCEDURE

Note

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

Tech Tips

Operating the engine 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 main wire and the branch wire.

      CAUTION:

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

      Note


      • After turning the engine 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 BRANCH WIRE)


    1. A00L0Z3E01
      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) Engine switch off 54 to 69 Ω

    NG

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

    OK

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


    1. A00L0Z3E02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Driving Support Switch Control ECU)

      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. 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

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

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

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE DRIVING SUPPORT SWITCH CONTROL ECU Click here