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) connectors are 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 control system is defective.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM

   
   

   1. Check if CAN communication system DTCs are output.

      for LHD: Click here

      for RHD: Click here

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

   
   

   B

   CHECK CAN COMMUNICATION SYSTEM for LHD: Click here CHECK CAN COMMUNICATION SYSTEM for RHD: 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. INSPECT BATTERY

   
   

   1. Check the battery voltage.

      Standard voltage
      11 to 14 V

      Result
      Proceed to OK NG

   
   

   NG

   CHECK OR REPLACE CHARGING SYSTEM OR BATTERY for 2AR-FE: Click here CHECK OR REPLACE CHARGING SYSTEM OR BATTERY for 2GR-FKS: Click here

   OK

4. CHECK TERMINAL VOLTAGE (IG1 TERMINAL)

   
   
   1. 

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

      Disconnect the A50 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 A50-12 (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) for 2AR-FE: Click here INSPECT STOP AND START SYSTEM (BACKUP BOOST CONVERTER CIRCUIT) for 2GR-FKS: Click here

   OK

5. CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)

   
   

   1. Turn the engine switch off.

   2. 

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition A50-25 (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 A50 skid control ECU (brake actuator assembly) connector.

   2. Connect the GTS to the DLC3.

   3. Turn the engine switch on (IG).

   4. Turn the GTS on.

   5. Select the Data List using 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

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

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

   
   

   A

   INSPECT METER / GAUGE SYSTEM Click here

   B

   REPLACE BRAKE ACTUATOR ASSEMBLY Click here