ELECTRONICALLY CONTROLLED BRAKE SYSTEM Excessive Brake Pedal Travel (No Fluid Leaks and No Air in System)

DESCRIPTION

Depending on the malfunction, the skid control ECU assembly prohibits operation of the electronically controlled brake system to protect components and prevent incorrect operation when DTCs are stored.

If the switching solenoid is disabled due to prohibition of the electronically controlled brake system, the response of the brake pedal changes and braking performance is reduced.

PROCEDURE

1. BRAKE PROBLEM CHECK

   
   

   1. Check the conditions at the time the problem occurred.

      
      

      1. Whether a warning light illuminated or the buzzer sounded.

      2. Road surface condition when the problem occurred and just before the problem occurred.

      3. When the problem occurred and how many times the brake pedal was depressed before the problem occurred.

      4. Frequency of the abnormal brake pedal response.

      Result
      Proceed to NEXT

   
   

   NEXT

2. CHECK DTC AND FREEZE FRAME DATA

   
   

   1. Using the GTS, check DTCs and Freeze Frame Data.

      Click here

      
      Chassis > ABS/VSC/TRC > Trouble Codes

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

      Tech Tips

      
      

      • If there are currently no warnings and the brake pedal travel is not excessive, DTCs may have been cleared after the system returned to normal.

      • If the brake pedal response returned to normal and there are currently no warnings, the system is normal.

   
   

   B

   REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

   A

3. CHECK BRAKE PEDAL

   
   

   1. While depressing the brake pedal by hand, check the installation condition of the brake pedal stroke sensor assembly and brake pedal, and check for mechanical malfunctions.

   2. Check and adjust the brake pedal height.

      for RHD: Click here

      for LHD: Click here

      Result
      Proceed to NEXT

   
   

   NEXT

4. INSPECT BRAKE MASTER CYLINDER SUB-ASSEMBLY AND BRAKE STROKE SIMULATOR CYLINDER SUB-ASSEMBLY

   
   

   1. Check the brake master cylinder sub-assembly and brake stroke simulator cylinder sub-assembly.

      Click here

      OK
      The brake master cylinder sub-assembly and brake stroke simulator cylinder sub-assembly are normal.

      Result
      Result Proceed to OK A NG (brake master cylinder sub-assembly) B NG (brake stroke simulator cylinder sub-assembly) C

   
   

   A

   USE SIMULATION METHOD TO CHECK Click here

   B

   REPLACE BRAKE MASTER CYLINDER SUB-ASSEMBLY for RHD: Click here REPLACE BRAKE MASTER CYLINDER SUB-ASSEMBLY for LHD: Click here

   C

   BRAKE STROKE SIMULATOR CYLINDER SUB-ASSEMBLY Click here