DTC C0040-9E: Brake Pedal Switch "A" Stuck On; DTC C0040-9F: Brake Pedal Switch "A" Stuck Off [11/2021 - ]: Procedure

1. Check if the same DTC is output.

   Chassis > Brake/EPB > Trouble Codes 

   HINT: 

   When P0571-11, P0571-12, and/or P0571-13 is output together with C0040-9E and/or C0040-9F, inspect and repair the trouble areas indicated by P0571-11, P0571-12, and/or P0571-13 first.

   Result

   Result	Proceed to
   C0040-9E and P0571-11 are output	A
   C0040-9E and P0571-12 are output	B
   C0040-9E and P0571-13 are output	C
   C0040-9F and P0571-11 are output	D
   C0040-9F and P0571-12 are output	E
   C0040-9F and P0571-13 are output	F
   Only C0040-9E or C0040-9F is output	G

Result: 

A 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

Result: 

B 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

Result: 

C 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

Result: 

D 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

Result: 

E 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

Result: 

F 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

Result: 

G 

See step  2

1. Check that the stop light switch display and brake pedal load sensing switch (brake pedal support assembly) display observed on the GTS change according to brake pedal operation.

   Chassis > Brake/EPB > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Stop Light SW	Stop light switch assembly (STP terminal input)	OFF / ON	OFF: Brake pedal released ON: Brake pedal depressed	HINT:  The brake pedal state is determined using the voltage at terminal STP
   Brake Pedal Load Sensing SW	Brake pedal load sensing switch (brake pedal support assembly) (FSW+ terminal input)	OFF / ON	OFF: Brake pedal load sensing switch (brake pedal support assembly) OFF ON: Brake pedal load sensing switch (brake pedal support assembly) ON	HINT:  The brake pedal state is determined using the voltage at terminal FSW+

   Chassis > Brake/EPB > Data List 

   Tester Display
   Stop Light SW
   Brake Pedal Load Sensing SW

   OK

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

2. Slowly depress the brake pedal, and check when the stop light switch and brake pedal load sensing switch (brake pedal support assembly) turn on.

   OK

   First the stop light switch turns on, and then the brake pedal load sensing switch (brake pedal support assembly) turns on.

   Result

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

Result: 

B 

See step  5

Result: 

C 

See step  7

Result: 

A 

See step  3

Pre-procedure1

1. None

   Procedure1

2. Clear the DTCs.

   Chassis > Brake/EPB > Clear DTCs 

   Result

   Proceed to
   NEXT

   Post-procedure1

3. Turn the ignition switch to off.

Result: 

NEXT 

See step  4

Pre-procedure1

1. Based on the Freeze Frame Data and interview with the customer, attempt to reproduce the conditions when the malfunction occurred.

   Procedure1

2. Check if the same DTC is output.

   Chassis > Brake/EPB > Trouble Codes 

   Result

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

   Post-procedure1

3. None

Result: 

A 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ] 

Result: 

B 

REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Refer to ON-VEHICLE INSPECTION [11/2021 - ] 

OK

The brake pedal load sensing switch (brake pedal support assembly) is normal.

Result

Result: 

NG 

REPLACE BRAKE PEDAL SUPPORT ASSEMBLY. Refer to  REMOVAL [11/2021 - 03/2022]  , or refer to  REMOVAL [03/2022 - ] 

Result: 

OK 

See step  6

Procedure1

1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

   OK

   The connector is securely connected.

   Pre-procedure1

2. Disconnect the A40 brake pedal load sensing switch (brake pedal support assembly) connector.
3. Disconnect the A36 skid control ECU (brake actuator assembly) connector.

   Procedure2

4. Check both the connector case and the terminals for deformation and corrosion.

   OK

   No deformation or corrosion.

   Procedure3

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A36-10 (FSW+) - A40-2 (FSW+)	Always	Below 1 Ω
   A36-10 (FSW+) or A40-2 (FSW+) - Body ground	Always	10 kΩ or higher
   A40-1 (FSW-) - Body ground	1 minute or more after disconnecting the cable from the negative (-) battery terminal	Below 1 Ω

   Result

   Proceed to
   OK
   NG

   Post-procedure1

6. None

Result: 

OK 

REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Pre-procedure1

1. Turn the ignition switch off.

   Procedure1

2. Check the brake pedal height and stop light switch assembly installation are normal.

   HINT: 

   Refer to ADJUSTMENT [11/2021 - ]

   OK

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

   Result

   Proceed to
   OK
   NG

   Post-procedure1

3. None

Result: 

OK 

REPLACE BRAKE PEDAL SUPPORT ASSEMBLY. Refer to  REMOVAL [11/2021 - 03/2022]  , or refer to  REMOVAL [03/2022 - ] 

Result: 

NG 

ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH ASSEMBLY. Refer to  ADJUSTMENT [11/2021 - ]