CAN COMMUNICATION SYSTEM ABS and Traction Actuator (Skid Control ECU) Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
ABS and Traction Actuator (Skid Control ECU) Communication Stop Mode

Either condition is met:


  • "Skid Control (ABS/VSC/TRAC)" is not displayed on "Bus Check".

  • "ABS and Traction Actuator (Skid Control ECU) Communication Stop Mode" in "DTC Combination Table" applies.

  • Power source or inside brake actuator assembly (skid control ECU)

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

  • Brake actuator assembly (skid control ECU)

  • Engine stop and start ECU*

WIRING DIAGRAM

A01IQXEE01
A01INS2E01

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. 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 CAN branch wire.

      CAUTION:

      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 (SKID CONTROL ECU CAN BRANCH WIRE)


    1. A01IUCSE01
      Text in Illustration
      *A for CVT
      *B for Manual Transaxle
      *a

      Front view of wire harness connector

      (to Brake Actuator Assembly [Skid Control ECU])

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

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

      Standard Resistance
      for CVT
      Tester Connection Switch Condition Specified Condition
      A78-26 (CANH) - A78-14 (CANL) Ignition switch off 54 to 69 Ω
      for Manual Transaxle
      Tester Connection Switch Condition Specified Condition
      A79-2 (CANH) - A79-16 (CANL) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE SKID CONTROL ECU CAN BRANCH WIRE OR CONNECTOR (CANH, CANL)

    OK

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


    1. A01IUCSE02
      Text in Illustration
      *A for CVT
      *B for Manual Transaxle
      *a

      Front view of wire harness connector

      (to Brake Actuator Assembly [Skid 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
      for CVT
      Tester Connection Condition Specified Condition
      A78-13 (GND2) - Body ground Always Below 1 Ω
      A78-38 (GND1) - Body ground Always Below 1 Ω
      for Manual Transaxle
      Tester Connection Condition Specified Condition
      A79-38 (GND2) - Body ground Always Below 1 Ω
      A79-14 (GND1) - Body ground Always Below 1 Ω

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

      Standard Voltage
      for CVT
      Tester Connection Condition Specified Condition
      A78-1 (+BM) - Body ground Always 11 to 14 V
      A78-25 (+BS) - Body ground Always 11 to 14 V
      for Manual Transaxle
      Tester Connection Condition Specified Condition
      A79-15 (+BM) - Body ground Always 11 to 14 V
      A79-1 (+BS) - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BATTERY)


    1. A01IUCSE03
      Text in Illustration
      *A for CVT
      *B for Manual Transaxle
      *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
      for CVT
      Tester Connection Switch Condition Specified Condition
      A78-28 (IG1) - Body ground Ignition switch ON 11 to 14 V
      for Manual Transaxle
      Tester Connection Switch Condition Specified Condition
      A79-4 (IG1) - Body ground Ignition switch ON 11 to 14 V
      Result
      Result Proceed to
      OK A
      NG (w/o Stop and Start System) B
      NG (w/ Stop and Start System) C

    B

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    C

    CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE STOP AND START ECU) Click here

    A

    REPLACE BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) Click here

  6. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE STOP AND START ECU)


    1. Disconnect the H121 engine stop and start ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A79-4 (IG1) - H121-12 (IGO1) Always Below 1 Ω
      A79-4 (IG1) or H121-12 (IGO1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ENGINE STOP AND START ECU Click here