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Pinpoint Test J: Excessive/Erratic Brake Pedal Travel


J: EXCESSIVE/ERRATIC BRAKE PEDAL TRAVEL
J1: TEST ON ROUGH ROAD
1. Road test the vehicle on rough road conditions.
2. Apply the brakes slowly.
- Is the brake pedal effort and brake pedal travel normal?
> Yes
Vehicle is OK.
> No
Go to J2

J2: CHECK BRAKE FLUID LEVEL
1. Check the brake master cylinder reservoir fluid level.
- Is the fluid level OK?
> Yes
Go to J3
> No
CHECK brake master cylinder reservoir sealing points. For additional information, refer to Hydraulic System. ADD brake fluid and BLEED the brake system. For additional information, refer to Brake Bleeding. TEST the system for normal operation. REPEAT road test if necessary.

J3: CHECK BRAKE PEDAL RESERVE
1. Engine is idle.
2. Apply the brake pedal lightly three or four times.
3. Wait 15 seconds for the vacuum to replenish.
4. Push down on the brake pedal until it stops moving downward or an increased resistance to the brake pedal travel occurs.
5. Hold the brake pedal in the applied position while increasing the engine speed to 2000 revs/min.
6. Release the accelerator pedal.
- Does the brake pedal move downward as the engine speed returns to idle?
> Yes
Go to J4
> No
CHECK the vacuum to the brake booster. For additional information, refer to Power Brake Booster.

J4: CHECK THE FRONT HUB AND BEARING ASSEMBLY
1. Check the front hub and bearing assembly. For additional information, refer to Transmission and Drivetrain.
- Are the front wheel bearings loose?
> Yes
INSTALL a new front wheel bearing if damaged. For additional information, refer to Transmission and Drivetrain.
TEST the system for normal operation.
> No
CHECK the front brake discs for thickness variances. For additional information, refer to Brake Bleeding.