Brake Warning Light Circuit

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: Brake Warning Light Circuit

Brake Warning Light Circuit

DESCRIPTION

The BRAKE warning light comes on when the brake fluid is insufficient, the parking brake is applied or the EBD is defective.

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTE: When replacing the ABS and TRACTION actuator assembly, perform zero point calibration (Programming and Relearning).

HINT: When releasing the parking brake, set the chocks to hold the vehicle for safety.

PROCEDURE

1. CHECK BRAKE FLUID
(a) Check that the brake fluid level is proper.
NG -- ADD BRAKE FLUID
OK -- Continue to next step.
2. INSPECT SKID CONTROL ECU CONNECTOR SECURELY CONNECTED
(a) Check the ECU connector's connecting condition.
OK:
The connector should be securely connected.
NG -- CONNECT CONNECTOR TO ECU CORRECTLY
OK -- Continue to next step.
3. CHECK DTC FOR ABS
(a) Are the DTCs recorded? (Vehicle Stability Control System)

NO -- INSPECT BRAKE WARNING LIGHT
YES -- REPAIR CIRCUIT INDICATED BY OUTPUT DTC
4. INSPECT BRAKE WARNING LIGHT
(a) WHEN USING TECHSTREAM:
(1) Connect Techstream to the DLC3.
(2) Start the engine.
(3) Select the "Brake Warning Light" in the Active Test and operate the BRAKE warning light by Techstream.

ABS / VSC / TRAC:

(4) Check that "ON" and "OFF" of the BRAKE warning light are indicated on the combination meter when using Techstream.
OK:
The BRAKE warning light turns on or off in accordance with Techstream.
(b) WHEN NOT USING TECHSTREAM:
(1) Turn the ignition switch off.
(2) Disconnect the skid control ECU connector.
(3) Turn the ignition switch to the ON position.
(4) Check that the BRAKE warning light.
OK:
The brake warning light comes on.
NG -- INSPECT PARKING BRAKE SWITCH
OK -- REPLACE ABS AND TRACTION ACTUATOR ASSEMBLY
5. INSPECT PARKING BRAKE SWITCH

(a) Remove the parking brake switch connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:

NG -- REPLACE PARKING BRAKE SWITCH
OK -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (PARKING BRAKE SWITCH - DAYTIME RUNNING LIGHT RELAY)

(a) Disconnect the daytime running light relay connector and parking brake switch connector.
(b) 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.
7. INSPECT DAYTIME RUNNING LIGHT RELAY
(a) Check the daytime running light relay.
NG -- REPLACE DAYTIME RUNNING LIGHT RELAY
OK -- Continue to next step.
8. CHECK HARNESS AND CONNECTOR (DAYTIME RUNNING LIGHT RELAY - SKID CONTROL ECU)

(a) Disconnect the skid control ECU connector and daytime running light relay connector.
(b) 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.
9. INSPECT BRAKE FLUID LEVEL WARNING SWITCH

(a) Remove the reservoir tank cap and strainer.
(b) Disconnect the brake fluid level warning switch connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:

NG -- REPLACE BRAKE MASTER CYLINDER RESERVOIR SUB-ASSEMBLY (BRAKE FLUID LEVEL WARNING SWITCH)
OK -- Continue to next step.
10. CHECK HARNESS AND CONNECTOR (BRAKE FLUID LEVEL WARNING SWITCH - COMBINATION METER)

(a) Disconnect the combination meter connector and the brake fluid level warning switch connector.
(b) 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.
11. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - COMBINATION METER)

(a) Disconnect the skid control ECU connector and combination meter connector.
(b) 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.
12. INSPECT COMBINATION METER ASSEMBLY
(a) Check combination meter assembly (Initial Inspection and Diagnostic Overview).
NG -- REPLACE COMBINATION METER ASSEMBLY
OK -- REPLACE ABS AND TRACTION ACTUATOR ASSEMBLY