Brake Booster Operating Test
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For simple checking of
the brake booster operation, carry out the following tests.
1. |
Run the engine for one or two minutes, and
then stop it. If the pedal depresses fully the first time but
gradually becomes higher when depressed succeeding times, the
booster is operating properly, if the pedal height remains
unchanged, the booster is inoperative.

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2. |
With the engine stopped, step on the brake
pedal several times.
Then step on the brake pedal and start the
engine. If the pedal moves downward slightly, the booster is in good
condition. If there is no change, the booster is
inoperative.

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3. |
With the engine running, step on the brake
pedal and then 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 inoperative.
If the above three tests are okay, the booster
performance can be determined as good.
Even if one of the above three tests is not
okay, check the check valve, vacuum hose and booster for
malfunction.

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1. |
Turn ignition switch OFF and disconnect the
negative (-) battery cable. |
2. |
Remove the battery (A) and ECM
(B).
(Refer to the Engine Electrical group -
"Battery")

|
3. |
Remove the master cylinder.
(Refer to Master
cylinder.) |
4. |
Disconnect the vacuum hose (A) from the brake
booster.

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5. |
Loosen the flare nuts (A) and then remove the
brake tube.
Tightening
torque:
18.6 ~ 22.6 N.m (1.9 ~ 2.3 kgf.m, 13.7 ~
16.6 lb-ft)
|

|
6. |
Loosen the brake tube bracket mounting nuts
(B).

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

|
8. |
Remove the brake booster mounting nuts
(A).
Tightening
torque:
18.6 ~ 23.5 N.m (1.9 ~ 2.4 kgf.m, 13.7 ~
17.4 lb-ft)
|

|
9. |
Pivot the brake tubes (A) down out of the
way.

|
10. |
Remove the gear actuator motor.
(Refer to the DCT system group - "DCT Control
System")
[DCT system
only] |
11. |
Remove the brake booster.
|
1. |
Inspect the check valve in the vacuum
hose.
Do not remove the check valve from the
vacuum
hose. | |
2. |
Check the boot for damage.
|
1. |
Installation is the reverse of
removal.
A. |
Before
installing the pin, apply the grease to the joint
pin. |
B. |
Use a new snap
pin whenever
installing. | |
2. |
After installing, bleed the brake system.
(Refer to Brake system
bleeding) |
3. |
Adjust the brake pedal height and free play.
(Refer to Brake pedal height and free play
adjustment) |