Excessive Brake Pedal Travel (No Fluid Leaks and No Air in System) [02/2024 - ]: Procedure

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

Result: 

NEXT 

See step  2

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

   Chassis > Brake Booster > Trouble Codes 

   Chassis > Brake/EPB > Trouble Codes 

   Result

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

   HINT: 

   • 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.

Result: 

B 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

Result: 

A 

See step  3

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.

   Refer to ADJUSTMENT [02/2024 - ]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  4

1. Check the brake booster with master cylinder assembly.

   Refer to PROCEDURE - Step 2

   OK

   The brake booster with master cylinder assembly is normal.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [02/2024 - ] 

Result: 

NG 

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to  REMOVAL [02/2024 - ]