VEHICLE STABILITY CONTROL SYSTEM ABS Warning Light Remains ON

DESCRIPTION

The skid control ECU (brake actuator assembly) is connected to the combination meter assembly via CAN communication. If any of the following is detected, the ABS warning light remains on:

• The skid control ECU (brake actuator assembly) connector is disconnected from the skid control ECU (brake actuator assembly).

• There is a malfunction in the skid control ECU (brake actuator assembly) internal circuit.

• There is an open in the harness between the combination meter and skid control ECU (brake actuator assembly).

• The ABS is defective.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM

   
   

   1. Check if CAN communication system DTCs are output.

      Click here

      Result
      Result Proceed to DTCs are not output. A DTCs are output. B

   
   

   B

   INSPECT CAN COMMUNICATION SYSTEM Click here

   A

2. CHECK IF BRAKE ACTUATOR ASSEMBLY CONNECTOR IS SECURELY CONNECTED

   
   

   1. Check if the skid control ECU (brake actuator assembly) connector is securely connected.

      OK
      The connector is securely connected.

      Result
      Proceed to OK NG

   
   

   NG

   CONNECT CONNECTOR TO ECU CORRECTLY

   OK

3. CHECK BATTERY

   
   

   1. Check the battery voltage.

      Standard Voltage
      11 to 14 V

      Result
      Result Proceed to OK A NG (for 8NR-FTS) B NG (for 3ZR-FAE) C

   
   

   B

   CHECK OR REPLACE CHARGING SYSTEM COMPONENT OR BATTERY Click here

   C

   CHECK OR REPLACE CHARGING SYSTEM COMPONENT OR BATTERY Click here

   A

4. CHECK HARNESS AND CONNECTOR (POWER SOURCE (IG1) TERMINAL)

   
   
   1. 

      *a	Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly))

      Disconnect the A42 skid control ECU (brake actuator assembly) connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition A42-30 (+BS) - Body ground Always 11 to 14 V

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

   OK

5. CHECK HARNESS AND CONNECTOR (POWER SOURCE (IG1) TERMINAL)

   
   
   1. 

      *a	Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly))

      Disconnect the A42 skid control ECU (brake actuator assembly) connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition A42-36 (IG1) - Body ground Ignition switch ON 11 to 14 V

      Result
      Result Proceed to OK A NG (w/ Stop and Start System) B NG (w/o Stop and Start System) C

   
   

   B

   GO TO STOP AND START SYSTEM Click here

   C

   REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

   A

6. CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)

   
   
   1. 

      *a	Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly))

      Turn the ignition switch off.

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

      Standard Resistance
      Tester Connection Condition Specified Condition A42-46 (GND1) - Body ground Always Below 1 Ω

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)

   OK

7. READ VALUE USING GTS (ABS WARNING LIGHT)

   
   

   1. Reconnect the A42 skid control ECU (brake actuator assembly) connector.

   2. Select the Data List on the GTS.

      Click here

      
      Chassis > ABS/VSC/TRC/EPB > Data List

      Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
      ABS Warning Light	ABS warning light	ON or OFF	ON: Warning light on OFF: Warning light off	-

      
      Chassis > ABS/VSC/TRC/EPB > Data List

      Tester Display
      ABS Warning Light

   3. Check the GTS display condition of the ABS warning light.

      Result
      Result Proceed to ON is displayed. (for LHD) A ON is displayed. (for RHD) B OFF is displayed. C

   
   

   A

   REPLACE BRAKE ACTUATOR ASSEMBLY Click here

   B

   REPLACE BRAKE ACTUATOR ASSEMBLY Click here

   C

   INSPECT METER / GAUGE SYSTEM Click here