Tool Required

J 28662 Brake Pedal Effort Gauge

1. Release the brake pedal.
2. Turn the ignition switch to the ON position.
3. Fully depress the brake pedal.
4. With the brake pedal depressed, turn the ignition switch to the LOCK position.
5. Inspect for a change in the brake pedal travel. If there is no change in the brake pedal travel, the vacuum booster is airtight.
6. If brake pedal travel exists after the engine is turned OFF, perform the following procedure:

6.1.	Install an operable check valve and hose.

6.2.	Release the brake pedal.

6.3.	Turn the ignition switch to the ON position.

6.4.	Fully depress the brake pedal.

6.5.	With the brake pedal depressed, turn the ignition switch to the LOCK position.

6.6.	If there is no change in the pedal travel, replace the check valve and hose.

6.7.	If brake pedal travel exists, replace the booster assembly. Refer to Power Vacuum Brake Booster Replacement .

7. Start the engine. Run the engine for 15 seconds.
8. Turn the ignition switch to the LOCK position.
9. Pump the brake pedal until all of the reserve is exhausted from the booster.
10. Using the J 28662 depress the brake pedal using a force of 294 N (66 lbs).
11. With the brake pedal depressed, turn the ignition switch to the ON position.
12. Inspect the brake pedal travel for the following conditions:

•	If the brake pedal moves slightly to the floor, a reserve brake pedal distance is present. The booster is functioning normally.

•	If the brake pedal does not move slightly to the floor, perform the following steps:

1.	Install an operable check valve and hose.

2.	Turn the ignition switch to the ON position.

3.	Run the engine for 15 seconds.

4.	Turn the ignition switch to the LOCK position.

5.	Pump the brake pedal until all of the reserve is exhausted from the booster.

6.	Using the J 28662 depress the brake pedal using a force of 294 N (66 lbs).

7.	With the brake pedal depressed, turn the ignition switch to the ON position.

8.	If the brake pedal moves slightly to the floor, replace the check valve and hose.

9.	If the brake pedal does not move slightly, replace the booster assembly.

13. Release the brake pedal.
14. Start the engine. Run the engine for 15 seconds.
15. Without depressing the brake pedal, turn the ignition switch to the LOCK position.
16. Depress the brake pedal several times slowly. Inspect the brake pedal travel for the following conditions:

•	If the brake pedal travel decreases with each brake pedal press, the booster is airtight and functioning normally.

•	If the brake pedal does not decrease in travel with each press, perform the following procedure:

1.	Install an operable check valve and hose.

2.	Start the engine. Run the engine for 15 seconds.

3.	Without depressing the brake pedal, turn the ignition switch to the LOCK position.

4.	Depress the brake pedal several times slowly.

5.	If the brake pedal travel decreases with each brake pedal press, replace the check valve and hose.

6.	If the brake pedal travel does not decrease, replace the booster assembly.