Brake Booster Test - Honda Accord 2008 Manual

07/11/02 09:32:42 61TA0000_190_0027

Brake Booster Test

Functional Test
1. With the ignition switch in LOCK (0), press the
brake pedal several times to deplete the vacuum
reservoir, then press the brake pedal hard, and hold
it for 15 seconds. If the brake pedal sinks, either the
master cylinder is bypassing internally, or the
brake system is leaking. Inspect the brake hoses
and lines (see page 19-38).
2. Start the engine with the brake pedal pressed. If the
brake pedal sinks slightly, the vacuum booster is
operating normally. If the brake pedal height does
not vary, do the brake system test (see page 19-4).
Leak Test
1. Press the brake pedal with the engine running, then
stop the engine. The brake pedal height should not
vary while pressed for 30 seconds. If the pedal
height rises, go to step 6. If it does not rise, go to
step 2.
2. Start the engine and let it idle for 30 seconds. Turn
the ignition switch to LOCK (0), and wait
30 seconds. Press the brake pedal several times
using normal pressure. When the pedal is first
pressed, it should be low. On consecutive
applications, the pedal height should gradually rise.
Does the pedal rise on each consecutive
application? If it rises, the booster is OK. If it does
not, go to step 3.
3. Disconnect the brake booster vacuum hose (A) at
the booster. The check valve (B) is built into the
hose.
NOTE: If the check valve is faulty, replace the brake
booster vacuum hose/check valve as an assembly.
B
4. Start the engine, and let it idle. There should be
vacuum available. If no vacuum is available, the
check valve is not working properly. Replace the
brake booster vacuum hose and the check valve,
and retest. If vacuum is found, go to step 5.
5. With the ignition switch at LOCK (0), reconnect the
vacuum hose to the brake booster.
6. Start the engine, and then pinch the brake booster
vacuum hose between the check valve and the
booster.
7. Turn the ignition switch to LOCK (0), and wait
30 seconds. Press the brake pedal several times
using normal pressure. When the pedal is first
pressed, it should be low. On consecutive
applications, the pedal height should gradually rise.
• If the pedal position does not vary, inspect the
seal between the master cylinder and the booster.
If the seal is OK, replace the brake booster.
• If the pedal position varies, replace the brake
booster vacuum hose/check valve as an
assembly.
ＴＡ０８Ａ００Ｄ１４３０００１４７０１ＦＥＡＴ００
＊０１
A
19-27