Brake booster

Components and Component Location

Components

Repair Procedures

Brake Booster Operation Test

To perform a simple check of brake booster operation, carry out the following inspections.

1. 1

   Start the engine, let it run for one to two minutes, then stop it. If the pedal initially falls fully but gradually rises higher in subsequent attempts, the booster is operating normally. If the pedal height remains unchanged, the booster is not operating.

   

2. 2

   With the engine stopped, depress the brake pedal several times.

   Then depress the brake pedal and start the engine. If the pedal moves slightly downward, the booster is in good condition. If there is no change, the booster is not operating.

   

3. 3

   With the engine running, depress the brake pedal and stop the engine. Hold the pedal depressed for 30 seconds. If the pedal height does not change, the booster is in good condition. If the pedal rises, the booster is not operating.

   If all three of the above tests are passed, booster performance may be reduced, but it is considered to be in good condition.

   If any one of the three tests above is unsatisfactory, inspect the check valve, vacuum hose, and booster for malfunction.

   

Removal

[Left-hand drive]

1. 1

   Turn the ignition switch OFF and disconnect the negative (-) battery cable.

2. 2

   Remove the brake fluid from the master cylinder reservoir using a syringe.

3. 3

   Remove the airbag lower panel.

   (Refer to Body - "Under Cover Panel")

4. 4

   Remove the knee airbag.

   (Refer to Passive Safety System - "Knee Airbag (KAB) Module").

5. 5

   Remove the lock pin (A) and the flat head pin (B).

   

6. 6

   Remove the brake booster mounting nuts (A).

   Tightening torque: 16.7–22 N·m

   

7. 7

   Remove the hood seal cover.

   

8. 8

   Remove the engine control module (ECM).

   D 2.2 R VGT (Refer to Engine Control/Fuel System - "Engine Control Module (ECM)").

   D 2.2 R VGT (Enhanced Euro 6) (Refer to Engine Control/Fuel System - "Engine Control Module (ECM)")

   G 2.0 T-GDI (Refer to Engine Control/Fuel System - "Engine Control Module (ECM)").

   G 3.3 T-GDI (Refer to Engine Control/Fuel System - "Engine Control Module (ECM)").

9. 9

   Disconnect the ISG connector.

   

10. 10

    Disconnect the brake vacuum hose (A) and the brake fluid level sensor connector (B).

    

11. 11

    Remove the master cylinder.

    (Refer to Brake System - "Master Cylinder")

12. 12

    Remove the brake booster.

[Right-hand drive]

1. 1

   Turn the ignition switch OFF and disconnect the negative (-) battery cable.

2. 2

   Remove the brake fluid from the master cylinder reservoir using a syringe.

3. 3

   Remove the airbag lower panel.

   (Refer to Body - "Under Cover Panel")

4. 4

   Remove the knee airbag.

   (Refer to Passive Safety System - "Knee Airbag (KAB) Module").

5. 5

   Remove the lock pin (A) and the flat head pin (B).

   

6. 6

   Remove the brake booster mounting nuts (A).

   Tightening torque: 16.7–22 N·m

   

7. 7

   Disconnect the wires (A) from the junction block.

8. 8

   Disconnect the junction block (B).

   Tightening torque: 10.8 - 13.7 N·m

   

9. 9

   Disconnect the vacuum sensor connector (A).

   

10. 10

    Disconnect the vacuum brake hose (A).

    

11. 11

    Remove the master cylinder.

    (Refer to Brake System - "Master Cylinder")

12. 12

    Remove the brake booster (A).

    

Inspection

1. 1

   Inspect the vacuum hose.

2. 2

   Check the boot for damage.

Installation

1. 1

   Install in the reverse order of removal.

2. 2

   After installation, bleed the brake system.

   (Refer to Brake System - "Brake Bleeding Procedures")