Brake Warning Light Remains ON

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: Brake Warning Light Remains ON
- Brake Warning Light Remains ON

DESCRIPTION

If any of the following conditions are detected, the BRAKE warning light remains on:

1. The ECU connector is disconnected from the skid control ECU.

2. The brake fluid level is insufficient.

3. The parking brake is applied.

4. The EBD system is malfunctioning.

5. The booster vacuum pressure is abnormal.

6. The pedal stroke sensor is malfunctioning.

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When replacing the VSC actuator assembly, perform zero point calibration Component Tests and General Diagnostics.

PROCEDURE

1. PREPARE FOR INSPECTION

(a) Check that both of the following conditions are satisfied.

* The brake fluid level in the brake master cylinder reservoir is correct.

* The parking brake is released.

HINT
* When the ABS warning light remains illuminated, repair the malfunction in the ABS system first.
* When the SLIP indicator light remains illuminated, repair the malfunction in the VSC system first.

NEXT -- Continue to next step.

2. CHECK DTC

(a) Check if any ABS DTCs are output Reading and Clearing Diagnostic Trouble Codes.

Result





B -- REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Vehicle Stability Control System
A -- Continue to next step.

3. INSPECT CAN COMMUNICATION SYSTEM

(a) Check if a CAN communication system DTC is output Initial Inspection and Diagnostic Overview.

Result





B -- GO TO CAN COMMUNICATION SYSTEM CAN Communication System
A -- Continue to next step.

4. CHECK CONNECTOR CONNECTION CONDITION

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

OK:

The connector is connected securely.

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

5. CHECK PARKING BRAKE SWITCH ASSEMBLY

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Select Data List mode and check the parking brake switch using the Techstream.

ABS/VSC/TRAC





(e) Check that ON and OFF are properly indicated on the Techstream display when the parking brake lever is operated.

OK:

Techstream display changes in accordance with the parking brake lever operation.

NG -- INSPECT PARKING BRAKE SWITCH ASSEMBLY
OK -- Continue to next step.

6. INSPECT BRAKE FLUID LEVEL WARNING SWITCH





(a) Remove the reservoir tank cap and strainer.

(b) Disconnect the A3 switch connector.

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

HINT
A float is placed inside the reservoir. Its position can be changed by increasing or decreasing the brake fluid level.

Standard Resistance:





HINT
If the result is as specified, adjust the brake fluid level to the MAX level after measuring the resistance.

NG -- REPLACE BRAKE MASTER CYLINDER RESERVOIR SUB-ASSEMBLY
OK -- Continue to next step.

7. CHECK HARNESS AND CONNECTOR (COMBINATION METER - BRAKE FLUID LEVEL WARNING SWITCH)

(a) Disconnect the J28 meter connector.





(b) Disconnect the A3 switch connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

8. INSPECT COMBINATION METER

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON and the Techstream on.

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

Combination Meter





(d) Check that the BRAKE warning light turns on and off in the combination meter using Techstream.

OK:

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

NG -- GO TO METER / GAUGE SYSTEM How To Proceed With Troubleshooting

OK -- REPLACE VSC ACTUATOR ASSEMBLY Removal

9. INSPECT PARKING BRAKE SWITCH ASSEMBLY

(a) Disconnect the A5 switch connector.





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

Standard Resistance:





NG -- REPLACE PARKING BRAKE SWITCH ASSEMBLY Disassembly
OK -- Continue to next step.

10. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - PARKING BRAKE SWITCH)

(a) Disconnect the A17 ECU connector.





(b) Disconnect the A5 switch connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE VSC ACTUATOR ASSEMBLY Removal