CAN COMMUNICATION SYSTEM(for RHD) Skid Control ECU Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Skid Control ECU Communication Stop Mode

Either condition is met:


  • Communication stop for "Skid Control (ABS/VSC/TRC)" is indicated on the "Communication Bus Check" screen of the GTS.

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  • Communication system DTCs (DTCs that start with U) that are output correspond to "Skid Control ECU Communication Stop Mode" in "DTC Combination Table".

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  • Power source circuit of brake actuator assembly (skid control ECU)

  • Brake actuator assembly (skid control ECU) ground circuit

  • Brake actuator assembly (skid control ECU) CAN branch wire or connector

  • Brake actuator assembly (skid control ECU)

WIRING DIAGRAM

B002DQ4E11

CAUTION / NOTICE / HINT

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

Note


  • Before measuring the resistance of the CAN bus, turn the engine switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.

  • After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

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  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.

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  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

  • DTC check procedure: Turn the engine switch on (IG) and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes or more.

  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.

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

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 FOR OPEN IN CAN BUS WIRE (BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) BRANCH WIRE)


    1. Disconnect the cable from the negative (-) battery terminal.

    2. B002CYRC17
      *a

      Front view of wire harness connector

      (to Brake Actuator Assembly (Skid Control ECU))

      Disconnect the brake actuator assembly (skid control ECU) connector.

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

      Standard Resistance
      Bus 2
      Tester Connection Condition Specified Condition
      A52-22 (CANH) - A52-10 (CANL) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Bus 4
      Tester Connection Condition Specified Condition
      A52-36 (CA2H) - A52-37 (CA2L) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU))

    OK

  2. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) - BATTERY AND BODY GROUND)


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

      Note

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

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    2. B002CYRC15
      *a

      Front view of wire harness connector

      (to Brake Actuator Assembly (Skid Control ECU))

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A52-12 (IG1) - Body ground Engine switch on (IG) 11 to 14 V
      A52-13 (BM) - Body ground Always 11 to 14 V
      A52-38 (+BS) - Body ground Always 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A52-25 (GND1) - Body ground Always Below 1 Ω
      A52-1 (GND2) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR