ABS Warning Light Remains On

BRAKE CONTROL: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: ABS Warning Light Remains ON

ABS Warning Light Remains ON

DESCRIPTION

The skid control ECU is connected to the combination meter via CAN and multiplex communications.
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.
HINT: In some cases, the Techstream cannot be used when the skid control ECU is abnormal.

WIRING DIAGRAM





INSPECTION PROCEDURE
NOTE:
When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration Programming and Relearning.

PROCEDURE

1. INSPECT CAN COMMUNICATION SYSTEM
(a) Check if the CAN communication system DTC is output Diagnosis System.
Result:






B -- REPAIR CAN COMMUNICATION SYSTEM
A -- Continue to next step.

2. INSPECT MULTIPLEX COMMUNICATION SYSTEM
(a) Check if the multiplex communication system DTC is output Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- REPAIR MULTIPLEX COMMUNICATION SYSTEM
A -- Continue to next step.

3. INSPECT IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED
(a) Check the skid control ECU connector's connecting condition.
OK:
The connector is securely connected.
NG -- CONNECT CONNECTOR TO ECU CORRECTLY
OK -- Continue to next step.

4. INSPECT BATTERY
(a) Check the battery voltage.
Voltage:
11 to 14 V
NG -- INSPECT CHARGING SYSTEM
OK -- Continue to next step.

5. INSPECT SKID CONTROL ECU (IG1 TERMINAL)




(a) Disconnect the skid control ECU connector.
(b) Turn the engine switch on (IG).
(c) Measure the voltage according to the value(s) in the table below.
Voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)
OK -- Continue to next step.

6. INSPECT SKID CONTROL ECU (GND TERMINAL)




(a) Disconnect the skid control ECU (A13, A15) connectors.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)
OK -- Continue to next step.

7. INSPECT COMBINATION METER ASSEMBLY
(a) Check the combination meter assembly Problem Symptoms Table.
HINT: If troubleshooting has been carried out according to the PROBLEM SYMPTOMS TABLE, refer back to the table and proceed to the next step before replacing the part Problem Symptoms Table.

NG -- REPLACE COMBINATION METER ASSEMBLY
OK -- REPLACE SKID CONTROL ECU