ABS Warning Light Remains ON

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM (for 2AZ-FE): 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 connector is disconnected from the skid control ECU.

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

* There is an open circuit malfunctioning in the harness between the combination meter and the skid control ECU.

* The ABS control system is malfunctioning.

HINT
In some cases, the Techstream cannot be used when the skid control ECU is abnormal.

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When replacing the brake actuator assembly, perform zero point calibration Programming and Relearning.

PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM

(a) Check if a CAN communication system DTC is output Diagnosis System.

Result:





B -- INSPECT CAN COMMUNICATION SYSTEM Initial Inspection and Diagnostic Overview
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 BATTERY

(a) Check the battery voltage.

Standard Voltage:

11 to 14 V

NG -- CHECK OR REPLACE CHARGING SYSTEM OR BATTERY (for 2AZ-FE) Component Tests and General Diagnostics
OK -- Continue to next step.

4. INSPECT SKID CONTROL ECU (IG1 TERMINAL)

(a) Disconnect the 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:





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

5. INSPECT SKID CONTROL ECU (GND1 TERMINAL)

(a) Turn the ignition switch off.





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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)
OK -- Continue to next step.

6. INSPECT COMBINATION METER ASSEMBLY

(a) Reconnect the skid control ECU connector.

(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 or off in accordance with the Techstream operation.

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 Removal

OK -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal