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 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.

HINT
* The master warning light will come on and a check ABS message will be displayed on the multi-information display if ABS control cannot be performed.
* In some cases, the Techstream cannot be used when the skid control ECU is malfunctioning.

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When replacing the skid control ECU, perform initialization and calibration of the linear solenoid valve Initialization.

PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM

(a) Check if a CAN communication system DTC is output (w/ Smart Key System: Diagnosis System, w/o Smart Key System: Diagnosis System).

Result:





C -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting

B -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting
A -- Continue to next step.

2. CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED

(a) Check if the skid control ECU connector is securely connected.

OK:

The connector is securely connected.

NG -- CONNECT CONNECTOR TO ECU CORRECTLY
OK -- Continue to next step.

3. CHECK AUXILIARY BATTERY

(a) Check the auxiliary battery voltage.

Standard Voltage:

11 to 14 V

NG -- CHARGE OR REPLACE AUXILIARY BATTERY
OK -- Continue to next step.

4. INSPECT SKID CONTROL ECU (IG1 TERMINAL)

(a) Disconnect the A44 skid control ECU connector.





(b) Turn the ignition switch to ON.

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

Standard Voltage:





Text in Illustration





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

5. INSPECT SKID CONTROL ECU (GND TERMINAL)

(a) Turn the ignition switch off.





Text in Illustration





(b) Disconnect the A45, A46 and A47 skid control ECU connectors.

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

Standard Resistance:





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

6. INSPECT COMBINATION METER ASSEMBLY

(a) Reconnect the skid control ECU connectors.

(b) Perform the Active Test of the combination meter (meter CPU) using the Techstream Meter / Gauge System.

(c) Check the combination meter.

OK:

The ABS warning light turns on and off in accordance with the Techstream operation.

HINT
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next suspected area before replacing the part Problem Symptoms Table.

NG -- REPLACE COMBINATION METER ASSEMBLY Removal

OK -- REPLACE SKID CONTROL ECU Removal