Vehicle Stability Control System Brake Warning Light Remains On

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK FOR DTC

CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED

CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU IG1 TERMINAL)

CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU GND1 TERMINAL)

CHECK BRAKE BOOSTER ASSEMBLY

INSPECT BRAKE FLUID LEVEL WARNING SWITCH

CHECK VACUUM WARNING SWITCH ASSEMBLY

INSPECT PARKING BRAKE SWITCH ASSEMBLY

CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - COMBINATION METER)

CHECK HARNESS AND CONNECTOR (COMBINATION METER - BODY GROUND)

READ VALUE USING INTELLIGENT TESTER (BRAKE WARNING LIGHT)

DESCRIPTION

1. The skid control ECU connector is disconnected from the skid control ECU.
   
2. The brake fluid level is insufficient.
   
3. The parking brake is applied.
   
4. The vacuum inside the brake booster decreases.
   
5. There is an open circuit in the harness between the combination meter and the skid control ECU.
   
6. EBD operation has been disabled.
   

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

1. When replacing the brake actuator assembly, perform zero point calibration (Toyota Fortuner RM000000XHR02TX.html).
   
2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.
   

1. Check for DTCs (Toyota Fortuner RM000000XHV03YX.html).
   

   Result

   Result	Proceed to
   DTC not output	A
   DTC output	B

1. Check if the skid control ECU connector is securely connected.
   

   OK:

   The connector is securely connected.
   

1. Turn the ignition switch off.
   

2. Disconnect the skid control ECU connector.
   

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

   Standard Voltage:

   Tester Connection	Switch Condition	Specified Condition
   S25-34 (IG1) - Body ground	Ignition switch ON	11 to 14 V

1. Turn the ignition switch off.
   

2. Disconnect the skid control ECU connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   S25-1 (GND1) - Body ground	Always	Below 1 Ω

1. Check the brake booster assembly (Toyota Fortuner RM0000010KJ00BX.html).
   

1. Turn the ignition switch off.
   

2. Remove the reservoir filler cap and strainer.
   

3. Disconnect the brake fluid level warning switch connector.
   

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

   HINT:

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   1 - 2	Brake fluid level warning switch OFF (Float up)	1.9 to 2.1 kΩ
   1 - 2	Brake fluid level warning switch ON (Float down)	Below 1 Ω

1. Turn the ignition switch off.
   

2. Disconnect the vacuum warning switch connector.
   

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   1 - 2	Engine idling	10 kΩ or higher
   1 - 2	Ignition switch off and brake pedal depressed a number of times to release vacuum	Below 1 Ω

1. Turn the ignition switch off.
   

2. Disconnect the parking brake switch connector.
   

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

   Standard Resistance:

   Tester Connection	Switch Condition	Specified Condition
   1 - Body ground	Parking brake switch ON (Switch pin free)	Below 1 Ω
   1 - Body ground	Parking brake switch OFF (Switch pin pushed in)	10 kΩ or higher

1. Turn the ignition switch off.
   

2. Disconnect the skid control ECU connector.
   

3. Disconnect the combination meter connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   S25-8 (BRL) - C10-26	Always	Below 1 Ω
   S25-8 (BRL) - Body ground	Always	10 kΩ or higher

1. Turn the ignition switch off.
   

2. Disconnect the combination meter connector.
   

3. Disconnect the skid control ECU connector.
   

4. Disconnect the brake fluid level warning switch connector.
   

5. Disconnect the vacuum warning switch connector.
   

6. Disconnect the parking brake switch connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   C10-36 - Body ground	Always	10 kΩ or higher

1. Turn the ignition switch off.
   

2. Connect the intelligent tester to the DLC3.
   

3. Turn the ignition switch to ON and the tester on.
   

4. Select the Data List mode on the intelligent tester (Toyota Fortuner RM000000XHW03RX.html).
   
   

   ABS/VSC/TRC

   Tester Display	Measurement Item / Range	Normal Condition	Diagnostic Note
   Brake Warning Light	Brake warning light / ON or OFF	ON: Brake warning light ON OFF: Brake warning light OFF	-

5. Perform the Active Test of the skid control ECU using the intelligent tester (Toyota Fortuner RM000000XHW03RX.html).