Excessive Brake Pedal Travel (No Fluid Leaks and No Air in System) [12/2019 - ]: Procedure
- PRE-INSPECTION
- Brake pedal inspection
- Perform a visual inspection and operate the brake pedal to check for any malfunctions.
- Check the brake pedal height, brake pedal free play and brake pedal reserve distance.
Refer to ADJUSTMENT [12/2019 - 10/2022] , or refer to ADJUSTMENT [10/2022 - ]
HINT:
If the brake pedal height is not within specification, confirm that there are no other malfunctions before adjusting the brake pedal height.
- Brake inspection
- Check that the disc brake pads of each wheel are installed correctly.
- Check that the bleeder plug and union bolt is not loose, and that there are no damaged gaskets or brake fluid leaks, for each wheel cylinder.
- Brake fluid leaks and air in brake line inspection
- Check and take a note of the fluid level in the brake master cylinder reservoir assembly.
- Repeatedly depress the brake pedal and confirm that the brake pedal feels normal (no air in the system, etc.).
- Check if the brake fluid level in the brake master cylinder reservoir assembly has changed.
- If the brake fluid level has decreased, check for leaks due to damaged brake lines or hoses, loose union nuts, damaged brake master cylinder sub-assembly seals, etc.
- Bleeding air from brake system
- Bleed air from the brake lines and brake actuator assembly.
Refer to BLEEDING [12/2019 - 10/2022] , or refer to BLEEDING [10/2022 - ]
Result
Proceed to NEXT - Bleed air from the brake lines and brake actuator assembly.
Result:
NEXT
See step 2
- Brake pedal inspection
- PERFORM ACTIVE TEST USING GTS (MOTOR RELAY)
- Fully depress and hold the brake pedal.
HINT:
Make sure that the brake pedal has travelled excessively before holding it depressed.
- Operate the motor relay using the Active Test and check if the brake pedal height changes when the pump motor is operating.
Chassis > Brake/EPB > Active Test
Tester Display Measurement Item Control Range Restrict Condition Diagnostic Note Motor Relay ABS motor relay OFF / ON Vehicle condition: Vehicle stopped
HINT:
To protect this Actuator and Solenoid, this test will only last 5 seconds.Refer to on-vehicle inspection for the brake actuator* - *: Refer to ON-VEHICLE INSPECTION [12/2019 - ]
Chassis > Brake/EPB > Active Test
Tester Display Motor Relay OK
The brake pedal height does not change (the brake pedal travel remains excessive).
Result
Proceed to OK NG
Result:
NG
REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to REMOVAL [12/2019 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023] , or refer to REMOVAL [11/2023 - ]
Result:
OK
See step 3
- Fully depress and hold the brake pedal.
- CHECK BRAKE MASTER CYLINDER SUB-ASSEMBLY
- Check that there are no brake fluid leaks and no indications of a malfunction in the brake master cylinder sub-assembly.
OK
There are no brake fluid leaks and no indications of a malfunction in the brake master cylinder sub-assembly.
Result
Proceed to OK NG
Result:
NG
REPLACE BRAKE MASTER CYLINDER SUB-ASSEMBLY. Refer to REMOVAL [12/2019 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023] , or refer to REMOVAL [11/2023 - ]
Result:
OK
See step 4
- Check that there are no brake fluid leaks and no indications of a malfunction in the brake master cylinder sub-assembly.
- INSPECT BRAKE BOOSTER ASSEMBLY
- Inspect operation of the brake booster assembly.
Refer to ON-VEHICLE INSPECTION [12/2019 - ]
OK
The brake booster assembly is normal.
Result
Proceed to OK NG
Result:
OK
USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - ]
Result:
NG
REPLACE BRAKE BOOSTER ASSEMBLY. Refer to REMOVAL [12/2019 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023] , or refer to REMOVAL [11/2023 - ]
- Inspect operation of the brake booster assembly.