DTC C0040-9E: Brake Pedal Switch "A" Stuck On; DTC C0040-9F: Brake Pedal Switch "A" Stuck Off [10/2018 - 07/2022]: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the engine switch on (IG).
3. Select the Data List using the Techstream.

   Refer to DATA LIST / ACTIVE TEST [10/2018 - 07/2022]

   Chassis > Brake/EPB > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Stop Light SW	Stop light switch	ON or OFF	ON: Brake pedal depressed OFF: Brake pedal released	-
   Brake Pedal Load Sensing SW	Brake pedal load sensing switch	ON or OFF	ON: Brake pedal depressed beyond a specified point OFF: Brake pedal not depressed beyond a specified point	-

4. Check that the stop light switch display and brake pedal load sensing switch display observed on the Techstream change according to brake pedal operation.

   OK

   The Techstream displays ON or OFF according to brake pedal operation.

5. Slowly depress the brake pedal, and check when the stop light switch and brake pedal load sensing switch turn on.

   OK

   First the stop light switch turns on, and then the brake pedal load sensing switch turns on.

   Result

   Result	Proceed to
   OK	A
   NG (Turning on of the brake pedal load sensing switch is not confirmed.)	B
   NG (The brake pedal load sensing switch turns on first.)	C

Result: 

B 

See step  3

Result: 

C 

See step  5

Result: 

A 

See step  2

1. Turn the engine switch off.
2. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [10/2018 - 07/2022]

3. Turn the engine switch off.
4. Start the engine.
5. Perform a road test.
6. Check if the same DTC is output.

   Refer to DTC CHECK / CLEAR [10/2018 - 07/2022]

   Result

   Result	Proceed to
   DTCs C0040-9E and C0040-9F are not output.	A
   DTCs C0040-9E and C0040-9F are output.	B

Result: 

A 

END 

Result: 

B 

REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [10/2018 - 07/2022] 

1. Turn the engine switch off.
2. Make sure that there is no looseness at the locking part and the connecting part of the connector.
3. Disconnect the A51 brake pedal load sensing switch (brake pedal support assembly) connector.
   NOTE:

   • Do not remove the brake pedal load sensing switch from the brake pedal support assembly.
   • When there is a malfunction in the brake pedal load sensing switch, replace the brake pedal support assembly.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component without harness connected (Brake Pedal Load Sensing Switch (Brake Pedal Support Assembly))

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   2 (FSW+) - 1 (FSW-)	Switch OFF (Brake pedal depressed)	950 to 1050 Ω
   2 (FSW+) - 1 (FSW-)	Switch ON (Brake pedal released)	203 to 223 Ω

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE BRAKE PEDAL SUPPORT ASSEMBLY. Refer to  REMOVAL [10/2018 - 07/2022] 

Result: 

OK 

See step  4

1. Make sure that there is no looseness at the locking part and the connecting part of the connector.
2. Disconnect the A38 skid control ECU (brake actuator assembly) connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A38-10 (HZRI) -A51-2 (FSW+)	Always	Below 1 Ω
   A38-10 (HZRI) - Body ground	Always	10 kΩ or higher
   A51-2 (FSW+) -Body ground	Always	10 kΩ or higher
   A51-1 (FSW-) -Body ground	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [10/2018 - 07/2022] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Turn the engine switch off.
2. Check the brake pedal height.

   Refer to ADJUSTMENT [10/2018 - 07/2022]

3. Check the stop light switch assembly installation.

   Refer to INSTALLATION [10/2018 - 07/2022]

   OK

   The brake pedal height and stop light switch assembly installation are normal.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE BRAKE PEDAL SUPPORT ASSEMBLY. Refer to  REMOVAL [10/2018 - 07/2022] 

Result: 

NG 

ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH ASSEMBLY. Refer to  ADJUSTMENT [10/2018 - 07/2022]