Note:
- The following testing methods allow you to easily determine the functionality of the brake booster.
- If any faults are detected in the vacuum booster, replace the booster with a new one.
Checks without using special equipment
1. With the engine stopped, press the brake pedal several times.
2. With the pedal pressed, start the engine.
3. If the brake pedal moves down slightly immediately after starting the engine, the brake booster is working properly.
4. Start the engine.
5. Stop the engine after 1-2 minutes of operation.
6. Press the brake pedal with normal force.
7. If the first stroke of the brake pedal is long enough and becomes shorter with each subsequent press, the brake booster is in good working order. If faults are detected, check the correct installation and the presence of damage to the check valve and vacuum hose. After repair, check the booster again.
8. Start the engine.
9. Press the brake pedal with normal force.
10. With the brake pedal depressed, stop the engine.
11. Keep the brake pedal depressed for approximately 30 seconds.
12. If the pedal height does not change over time, the vacuum booster is normal.
Checks using special equipment
Note:
- When performing a check using special equipment, check the brake lines of the left and right front wheels.
- The following figures show the inspection procedures for the left front wheel brake line.
1. Remove the fasteners.
2. Move the mudguard aside.
3. Disconnect the brake line from the brake hose.
4. Remove the clamp.
5. Remove the brake hose from the bracket.
6. Disconnect the brake line from the line holder.
7. Install the special equipment on the brake pipe as shown in the figure.
8. Remove air from the brake line and special equipment.
Note: Remove air from the special equipment through connection A.
9. Install a device for measuring the force on the brake pedal.
10. Connect the vacuum gauge to the vacuum line.
11. Start the engine.
12. Press the brake pedal with a force of 200 N (20.4 kgf).
13. Stop the engine when the vacuum gauge reading reaches 68 kPa (510 mmHg.) with the pedal pressed.
14. With the engine off, monitor the vacuum gauge for 15 seconds.
15. If the vacuum drops by 3.3 kPa (25 mmHg.) or less, the amplifier is working properly.
16. If the ratio of the force on the brake pedal and the brake fluid pressure corresponds to the values given in the table with the engine stopped and the vacuum value of 0 kPa (About mmHg.), the system is working properly.
17. Start the engine. When the vacuum value reaches 66.7 kPa (500 mmHg.), press the brake pedal with a force of 200 N and check the brake fluid pressure value. If the results obtained are normal, the system is in good working order.
18. After completing the check, remove the special equipment, install the brake hoses and pipes in their places and remove air from the brake system.