ANTI-LOCK BRAKE 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 anti-lock brake system is defective.

• The voltage at terminal IG1 is high.

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
      DTC not output	A
      DTC output	B

   
   

   B

   GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here

   A

2. CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED

   
   

   1. Check if the skid control ECU connector is securely connected.

      OK
      The connector is securely connected.

   
   

   NG

   CONNECT CONNECTOR TO ECU CORRECTLY

   OK

3. CHECK TERMINAL VOLTAGE (IG1)

   
   

   1. Disconnect the A6 skid control ECU (brake actuator assembly) connector.

   2. 

      Text in Illustration

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

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition A6-34 (IG1) - Body ground Ignition switch ON 11 to 14 V

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)

   OK

4. CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)

   
   

   1. Disconnect the A6 skid control ECU (brake actuator assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition A6-1 (GND1) - Body ground Always Below 1 Ω

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)

   OK

5. READ VALUE USING GTS (ABS WARNING LIGHT)

   
   

   1. Turn the ignition switch off.

   2. Connect the GTS to the DLC3.

   3. Turn the ignition switch to ON.

   4. Turn the GTS on.

   5. Enter the following menus: Chassis / ABS/VSC/TRC / Data List.

      ABS/VSC/TRC

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

   6. When performing the ABS Warning Light Active Test, check ABS Warning Light in the Data List (See Page ).

      ABS/VSC/TRC

      Tester Display	Test Part	Control Range	Diagnostic Note
      ABS Warning Light	ABS warning light	Warning light ON/OFF	Observe the combination meter.

      Result

      Result		Proceed to
      Data List Display	Data List Display when Performing Active Test ON/OFF Operation
      ON	Does not change between ON and OFF	A
      	Changes between ON and OFF	B
      OFF	Does not change between ON and OFF	A
      	Changes between ON and OFF	B

      Click here

   
   

   A

   REPLACE BRAKE ACTUATOR ASSEMBLY Click here

   B

   GO TO METER / GAUGE SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Click here