Anti-Lock Brake System Brake Warning Light Remains On

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT BRAKE FLUID LEVEL WARNING SWITCH

INSPECT PARKING BRAKE SWITCH ASSEMBLY

INSPECT VACUUM WARNING SWITCH ASSEMBLY

CHECK HARNESS AND CONNECTOR (BRAKE WARNING LIGHT CIRCUIT)

INSPECT SKID CONTROL ECU (PKB INTERNAL CIRCUIT)

DESCRIPTION

1. The brake fluid level is insufficient.
   
2. The parking brake is applied.
   
3. The vacuum inside the brake booster decreases (for 1KD-FTV and 2KD-FTV).
   
4. The PKB terminal circuit is shorted.
   

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

1. for 1KD-FTV and 2KD-FTV:
   If there is a brake booster system malfunction, such as a problem with the response of the brake pedal when it is depressed, inspect the brake booster system first.
   
1. For brake booster inspection:
   
1. On-vehicle inspection:
   
2. for TMT Made: HILUX_TGN26 RM0000010KJ00YX.html
   
3. for TASA Made: HILUX_TGN26 RM0000010KJ013X.html
   
4. Inspection:
   
5. for TMT Made: HILUX_TGN26 RM000004QMH002X.html
   
6. for TASA Made: HILUX_TGN26 RM000004Z5O000X.html
   
1. For vacuum pump inspection:
   
1. On-vehicle inspection: HILUX_TGN26 RM0000010KP014X.html
   
2. Inspection: HILUX_TGN26 RM0000010LK00ZX.html
   
2. Before disconnecting the connector, make sure that there are no problems with the connection.
   
3. After disconnecting the connector, make sure that the connector case and terminals are not deformed or corroded.
   

1. Turn the ignition switch to ON.
   

2. With the brake fluid at the specified level, disconnect the brake fluid level warning switch (brake master cylinder reservoir sub-assembly) connector and check the brake warning light.
   

   Result

   Result	Proceed to
   Brake warning light does not turn off	A
   Brake warning light turns off (for TMT Made)	B
   Brake warning light turns off (for TASA Made)	C

   HINT:

   If the brake warning light turns off, the brake fluid level warning switch (brake master cylinder reservoir sub-assembly) has an internal short circuit.

1. Turn the ignition switch off.
   

2. Remove the parking brake switch (HILUX_TGN26 RM000001C4X01LX.html).
   

3. Inspect the parking brake switch (HILUX_TGN26 RM000001C4V01MX.html).
   

   Result

   Result	Proceed to
   OK (for 1KD-FTV and 2KD-FTV)	A
   OK (except 1KD-FTV and 2KD-FTV)	B
   NG	C

1. Start the engine.
   

2. Idle the engine.
   

3. Disconnect the vacuum warning switch connector and check the brake warning light.
   

   Result

   Result	Proceed to
   Brake warning light does not turn off	A
   Brake warning light turns off (for TMT Made)	B
   Brake warning light turns off (for TASA Made)	C

   HINT:

   If the brake warning light turns off, the vacuum warning switch has an internal short circuit.

1. Turn the ignition switch off.
   

2. Disconnect the skid control ECU (brake actuator assembly) connector.
   

3. Disconnect the G19 combination meter connector.
   

4. Disconnect the parking brake switch connector.
   

5. Disconnect the brake fluid level warning switch (brake master cylinder reservoir sub-assembly) connector.
   

6. for 1KD-FTV and 2KD-FTV:
   Disconnect the vacuum warning switch connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   A13-18 (PKB) - G19-36 (SW)	Always	Below 1 Ω
   A13-18 (PKB) - Body ground	Always	10 kΩ or higher

1. Turn the ignition switch off.
   

2. Release the parking brake.
   

3. Start the engine.
   

4. Disconnect the skid control ECU (brake actuator assembly) connector and check the brake warning light.
   

   Result

   Result	Proceed to
   Brake warning light does not turn off	A
   Brake warning light turns off	B

   HINT:

   If the brake warning light turns off, the skid control ECU (brake actuator assembly) has an internal short circuit.