DTC C13B4: EPB Switch Malfunction [06/2017 - 10/2020]: Procedure

1. Inspect the electric parking brake switch (electric parking brake switch assembly).

   Refer to INSPECTION [06/2017 - ]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE ELECTRIC PARKING BRAKE SWITCH (ELECTRIC PARKING BRAKE SWITCH ASSEMBLY). Refer to  REMOVAL [06/2017 - ] 

Result: 

OK 

See step  2

1. Disconnect the K37 electric parking brake switch (electric parking brake switch assembly) connector.
2. Disconnect the A34 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
   A34-31 (SWI1) - K37-9 (SWI1)	Always	Below 1 Ω
   A34-32 (SWO1) - K37-10 (SWO1)	Always	Below 1 Ω
   A34-15 (SWI2) - K37-1 (SWI2)	Always	Below 1 Ω
   A34-16 (SWO2) - K37-2 (SWO2)	Always	Below 1 Ω
   A34-31 (SWI1) or K37-9 (SWI1) - Body ground	Always	10 kΩ or higher
   A34-32 (SWO1) or K37-10 (SWO1) - Body ground	Always	10 kΩ or higher
   A34-15 (SWI2) or K37-1 (SWI2) - Body ground	Always	10 kΩ or higher
   A34-16 (SWO2) or K37-2 (SWO2) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  3

1. Clear the DTCs.

   Chassis > ABS/VSC/TRAC/EPB > Clear DTCs 

2. Turn the engine switch off.
3. Turn the engine switch on (IG).
4. Check for DTCs.

   Chassis > ABS/VSC/TRAC/EPB > Trouble Codes 

   Result

   Result	Proceed to
   DTCs are output	A
   DTCs are not output	B

Result: 

A 

REPLACE SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY). Refer to  REMOVAL [06/2017 - 10/2020] 

Result: 

B 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [06/2017 - 08/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2018 - 09/2019]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2019 - 03/2020]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [03/2020 - 10/2020]