Hyundai Elantra Owners and Service Manuals

Hyundai Elantra: Brake System / Brake Booster

Hyundai Elantra (CN7) 2021-2025 Service Manual / Brake System / Brake System / Brake Booster

Components and components location
Components

1. Reservoir cap
2. Reservoir
3. Brake fluid lever sensor
4. Master cylinder
5. Brake booster
6. Push road

Repair procedures
Brake Booster Operating Test
1.
Start the engine for 1 - 2 minutes and stop. If the brake stroke gradually reduces when the brake is pressed for several times, it means it works properly. But if the brake stroke doesn't change, inspect the check valve, vacuum hose and booster.

2.
Turn the engine off. And press the pedal for several times until the brake stroke reduces. And then, start the engine and press the pedal. When there is no change in brake stroke, it means the brake works properly. If it is not, inspect the check valve, vacuum hose and booster.
3.
Press the pedal and stop the engine when the engine is running. Press the pedal for 30 seconds. When the position is fixed, It means that there is nothing wrong in the check valve, vacuum hose and booster. But if the pedal tries to return to its original position, the one before pressing, inspect the check valve, vacuum hose and booster for proper operation.

The booster can be seen that it works properly if it passes all three tests stated above. But if it fails to one of the tests, check the check valve, vacuum hose and booster.
Removal
[LHD]
1.
Turn ignition switch OFF and disconnect the negative (-) battery cable.
2.
Remove the battery and battery tray.
(Refer to Engine Electrical System - "Battery")
3.
Remove the master cylinder.
(Refer to Brake System - "Brake Master Cylinder")
4.
Remove the fixing clip and the vacuum hose (A) from the brake booster.

5.
Remove the snap pin (A) and the clevis pin (B).

6.
Loosen the fixed nut (A) and then removing the brake booster (B).
Tightening torque :
16.7 - 25.5 N.m (1.7 - 2.6 kgf.m, 12.3 - 18.8 lb-ft)

[RHD]
1.
Turn ignition switch OFF and disconnect the negative (-) battery cable.
2.
Remove the master cylinder.
(Refer to Brake System - "Brake Master Cylinder")
3.
Remove the roll rod bracket.
(Refer to Engine Mechanical System - "Engine Mounting")
4.
Remove the engine mounting bracket.
(Refer to Engine Mechanical System - "Engine Mounting")
5.
Remove the fixing clip and the vacuum hose (A) from the brake booster.

6.
Remove the snap pin (A) and the clevis pin (B).

7.
Loosen the fixed nut (A) and then removing the brake booster (B).
Tightening torque :
16.7 - 25.5 N.m (1.7 - 2.6 kgf.m, 12.3 - 18.8 lb-ft)

[G 1.6 T-GDI]
1.
Turn ignition switch OFF and disconnect the negative (-) battery cable.
2.
Drain the coolant.
(Refer to Engine Mechanical System - "Coolant")
3.
Remove the battery and battery tray.
(Refer to Engine Electrical System - "Battery")
4.
Remove the master cylinder.
(Refer to Brake System - "Brake Master Cylinder")
5.
Disconnect the heater hose quick connector (A) from the heater pipe.

6.
Remove the fixing clip and the vacuum hose (A) from the brake booster.

7.
Remove the snap pin (A) and the clevis pin (B).

8.
Loosen the fixed nut (A) and then removing the brake booster (B).
Tightening torque :
16.7 - 25.5 N.m (1.7 - 2.6 kgf.m, 12.3 - 18.8 lb-ft)

Inspection
1.
Inspect the vacuum hose.
2.
Check the boot for damage.
Installation
1.
To install, reverse the removal procedure.
   
•
Before installing the pin, apply the grease to the joint pin.
•
Use a new snap pin whenever installing.
2.
Refill the coolant. [G 1.6 T-GDI]
(Refer to Engine Mechanical System - "Coolant")
3.
After installation, bleed the brake system.
(Refer to Brake System - "Brake Bleeding Prcoedures")
4.
Check the brake oil leakage and pedal operating condition.

    Repair procedures

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    Master Cylinder

    Components and components location Components1. Reservoir cap2. Reservoir3. Brake fluid lever sensor4. Master cylinder5. Brake booster6. Push road Repair procedures Removal[LHD]1...

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