Brake Warning Light Remains ON [08/2015 - 08/2019]: Procedure

See step  1

Result: 

B 

CHECK CAN COMMUNICATION SYSTEM 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2019] )

Result: 

A 

See step  2

See step  2

Result: 

NG 

CONNECT CONNECTOR TO BRAKE ACTUATOR ASSEMBLY CORRECTLY 

Result: 

OK 

See step  3

See step  3

Result: 

NG 

CHECK OR REPLACE CHARGING SYSTEM OR BATTERY 

Result: 

OK 

See step  4

Refer to PROCEDURE - Step 1

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT) 

Result: 

OK 

See step  5

Refer to PROCEDURE - Step 2

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT) 

Result: 

OK 

See step  6

1. Turn the ignition switch off.
2. Remove the reservoir filler cap and strainer.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

3. Disconnect the A54 brake fluid level warning switch (master cylinder reservoir assembly) 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	Switch off (Float up)	Below 1 Ω
   	Switch on (Float down)	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *a	Component without harness connected (Brake Fluid Level Warning Switch (Master Cylinder Reservoir Assembly))

   HINT: 

   If there is no problem after finishing the above check, adjust the brake fluid level to the MAX level.

Result: 

NG 

REPLACE BRAKE MASTER CYLINDER RESERVOIR ASSEMBLY 

(Refer to REMOVAL [08/2015 - ] )

Result: 

OK 

See step  7

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   F14-14 (SW) or A54-1 - Body ground	Always	10 kΩ or higher

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  8

1. Disconnect the A2 parking brake switch assembly connector.
2. Inspect the parking brake switch assembly (Refer to INSPECTION [08/2015 - ] ).

   OK

   The parking brake switch assembly is normal.

Result: 

NG 

REPLACE PARKING BRAKE SWITCH ASSEMBLY 

(Refer to REMOVAL [08/2015 - 08/2019] )

Result: 

OK 

See step  9

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   2D-17 or A2-1 - Body ground	Always	10 kΩ or higher

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  10

1. Reinstall the reservoir filler cap and strainer.
2. Reconnect the F14 combination meter assembly connector, the A54 brake fluid level warning switch (master cylinder reservoir assembly) connector, A2 parking brake switch assembly connector and A53 skid control ECU (brake actuator assembly) connector.
3. Connect the Techstream to the DLC3.
4. Turn the ignition switch to ON.
5. Turn the Techstream on.
6. Enter the following menus: Chassis / ABS/VSC/TRAC / Data List.
7. According to the display on the Techstream, read the Data List.
   ABS/VSC/TRAC
   
   

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

8. Check the Techstream display condition of the brake warning light.

   Result

   Result	Proceed to
   Display of the Data List remains OFF	A
   Display of the Data List remains ON	B

Result: 

A 

INSPECT METER / GAUGE SYSTEM 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - ] )

Result: 

B 

REPLACE BRAKE ACTUATOR ASSEMBLY 

(Refer to REMOVAL [08/2015 - 08/2019] )