CAN COMMUNICATION SYSTEM(for LHD) 4WD Control ECU Communication Stop Mode

DESCRIPTION

Detection Item DTC Detection Condition Trouble Area
4WD Control ECU Communication Stop Mode

Either Condition is met:


  • ""Four Wheel Drive Control" is not displayed on the "Bus Check" screen.

  • "4WD Control ECU Communication Stop Mode" in "DTC Combination Table" applies.

  • Power source or inside of 4WD control ECU

  • 4WD control ECU CAN branch wire or connector

  • 4WD control ECU

WIRING DIAGRAM

A01X0YME03
*a No. 1 Junction Connector
*b from IG1 NO. 1 Relay
*c 4WD Control ECU

CAUTION / NOTICE / HINT

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. PRECAUTION

    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.


    NEXT

  2. 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:

      For vehicles with an SRS system:

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

      Note

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


    NEXT

  3. CHECK FOR OPEN IN CAN BUS WIRE (4WD CONTROL ECU CAN BRANCH WIRE)


    1. A01XBQDE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to 4WD Control ECU)

      Disconnect the A27 4WD control ECU connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      A27-19 (CAN+) - A27-20 (CAN-) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE 4WD CONTROL ECU BRANCH WIRE OR CONNECTOR (CANH, CANL)

    OK

  4. CHECK HARNESS AND CONNECTOR (4WD CONTROL ECU - BATTERY AND BODY GROUND)


    1. A01X7IDE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to 4WD 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. Disconnect the A28 4WD control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A28-4 (GND) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A28-3 (IG) - Body ground Ignition switch ON 11 to 14 V

    OK

    REPLACE 4WD CONTROL ECU Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR