CAN COMMUNICATION SYSTEM Skid Control ECU Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Skid Control ECU Communication Stop Mode

  • "ABS/VSC/TRC" is not displayed on "Communication Bus Check" screen of the intelligent tester.

  • Applies to Skid Control ECU Communication Stop Mode in DTC Combination Table.

  • Skid control ECU branch wire or connector

  • Power source circuit of skid control ECU

  • Brake actuator assembly (Skid control ECU)

WIRING DIAGRAM

A019OQ3E06
A019MJ4E01

INSPECTION PROCEDURE

Note


  • Turn the engine switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.

  • Turn the engine switch off before inspecting CAN bus wires for a ground short.

  • After the engine switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.

  • Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the engine switch, any other switches or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.

Tech Tips


  • Operating the engine switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.

  • Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE


  1. CHECK CAN BUS WIRE FOR DISCONNECTION (SKID CONTROL ECU BRANCH WIRE)


    1. Turn the engine switch off.

    2. A019MT5E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU)

      Disconnect the skid control ECU connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      A44-25 (CANH) - A44-14 (CANL) Engine switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (SKID CONTROL ECU BRANCH WIRE)

    OK

  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)


    1. A019MT5E02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU)

      Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A44-34 (IG1) - Body ground Engine switch on (IG) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

    OK

  3. CHECK HARNESS AND CONNECTOR (GROUND TERMINAL)


    1. A019MT5E03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU)

      Turn the engine switch off.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A44-1 (GND1) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GROUND CIRCUIT)

    OK

    REPLACE BRAKE ACTUATOR (SKID CONTROL ECU)