DTC C13B4: EPB Switch Malfunction [04/2018 - 08/2021]: Procedure

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

   Refer to INSPECTION [04/2018 -]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE ELECTRIC PARKING BRAKE SWITCH (ELECTRIC PARKING BRAKE SWITCH ASSEMBLY). Refer to  REMOVAL [04/2018 -] 

Result: 

OK 

See step  2

1. Disconnect the G24 electric parking brake switch (electric parking brake switch assembly) connector.
2. Disconnect the A39 parking brake 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
   A39-14 (SWI1) - G24-9 (SWI1)	Always	Below 1 Ω
   A39-20 (SWO1) - G24-10 (SWO1)	Always	Below 1 Ω
   A39-24 (SWI2) - G24-1 (SWI2)	Always	Below 1 Ω
   A39-22 (SWO2) - G24-2 (SWO2)	Always	Below 1 Ω
   A39-14 (SWI1) or G24-9 (SWI1) - Body ground	Always	10 kΩ or higher
   A39-20 (SWO1) or G24-10 (SWO1) - Body ground	Always	10 kΩ or higher
   A39-24 (SWI2) or G24-1 (SWI2) - Body ground	Always	10 kΩ or higher
   A39-22 (SWO2) or G24-2 (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 > Electric Parking Brake > Clear DTCs 

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

   Chassis > Electric Parking Brake > Trouble Codes 

   Result

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

Result: 

A 

REPLACE PARKING BRAKE ECU (BRAKE ACTUATOR ASSEMBLY). Refer to  REMOVAL [04/2018 - 08/2021] 

Result: 

B 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [04/2018 -]