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 assembly and the 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 BRAKE ACTUATOR ASSEMBLY CORRECTLY

   OK

3. CHECK BATTERY

   
   

   1. Check the battery voltage.

      Standard Voltage
      Tester Connection Condition Specified Condition Positive (+) terminal - Negative (-) terminal Always 11 to 14 V

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

   
   

   B

   CHECK HARNESS AND CONNECTOR (IG1 TERMINAL) Click here

   C

   CHECK OR REPLACE CHARGING SYSTEM COMPONENT OR BATTERY for 2GR-FKS: Click here CHECK OR REPLACE CHARGING SYSTEM COMPONENT OR BATTERY for 8AR-FTS: Click here

   A

4. CHECK HARNESS AND CONNECTOR (IG1 TERMINAL)

   
   
   1. 

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

      Disconnect the A94 skid control ECU (brake actuator assembly) connector.

   2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Condition Specified Condition A94-12 (IG1) - Body ground Engine switch on (IG) 10.5 to 16 V

      Result
      Proceed to OK NG

   
   

   NG

   INSPECT STOP AND START SYSTEM (BACKUP BOOST CONVERTER CIRCUIT) Click here

   OK

5. CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)

   
   
   1. 

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

      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 A94-25 (GND1) - Body ground Always Below 1 Ω

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)

   OK

6. READ VALUE USING GTS (ABS WARNING LIGHT)

   
   

   1. Reconnect the A94 skid control ECU (brake actuator assembly) connector.

   2. Connect the GTS to the DLC3.

   3. Turn the engine switch on (IG).

   4. Select the Data List on the GTS.

      Click here

      
      Chassis > ABS/VSC/TRC > 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 > Data List

      Tester Display
      ABS Warning Light

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

      Result
      Result Proceed to ON is displayed. A OFF is displayed. B

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts.

      Click here

   
   

   A

   REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here

   B

   INSPECT METER / GAUGE SYSTEM Click here

7. CHECK HARNESS AND CONNECTOR (IG1 TERMINAL)

   
   
   1. 

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

      Disconnect the A94 skid control ECU (brake actuator assembly) connector.

   2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Condition Specified Condition A94-12 (IG1) - Body ground Engine switch on (IG) 11 to 14 V

      Result
      Proceed to OK NG

   
   

   OK

   GO TO STEP 5 Click here

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)