ELECTRONICALLY CONTROLLED BRAKE SYSTEM ABS Warning Light Remains ON

DESCRIPTION

The skid control ECU is connected to the combination meter via CAN communication.

If any of the following is detected, the ABS warning light remains on:

• The skid control ECU connectors are disconnected from the skid control ECU.

• There is a malfunction in the skid control ECU internal circuit.

• There is an open in the harness between the combination meter and the skid control ECU.

• The ABS control system is defective.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM

   
   

   1. Check if a CAN communication system DTC is output Click here.

      Result
      Result Proceed to DTC is not output A DTC is output B

   
   

   B

   INSPECT CAN COMMUNICATION SYSTEM 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 AUXILIARY BATTERY

   
   

   1. Check the auxiliary battery voltage.

      Standard Voltage
      11 to 14 V

   
   

   NG

   CHARGE OR REPLACE AUXILIARY BATTERY

   OK

4. INSPECT SKID CONTROL ECU (IG1 TERMINAL)

   
   
   1. 

      Text in Illustration

      *1	Front view of wire harness connector (to Skid Control ECU)

      Disconnect the skid control ECU connector.

   2. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition A90-2 (IG1) - Body ground Power switch on (IG) 11 to 14 V

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)

   OK

5. INSPECT SKID CONTROL ECU (GND TERMINAL)

   
   

   1. Turn the power switch off.

      

      Text in Illustration

      *1

      Front view of wire harness connector (to Skid Control ECU)

      -

      -

   2. Disconnect the skid control ECU connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition A89-1 (GND) - Body ground Always Below 1 Ω A90-3 (GND2) - Body ground Always Below 1 Ω A90-1 (GND3) - Body ground Always Below 1 Ω A91-3 (GND4) - Body ground Always Below 1 Ω A91-1 (GND5) - Body ground Always Below 1 Ω A92-3 (GND6) - Body ground Always Below 1 Ω

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)

   OK

6. INSPECT COMBINATION METER ASSEMBLY

   
   

   1. Reconnect the skid control ECU connectors.

   2. Perform the Active Test of the combination meter (meter CPU) using the intelligent tester Click here.

   3. Check the combination meter.

      OK
      The ABS warning light turns on or off in accordance with the intelligent tester operation.

      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 the part Click here.

   
   

   NG

   REPLACE COMBINATION METER ASSEMBLY Click here

   OK

   REPLACE SKID CONTROL ECU Click here