air bleeding AUDI A4 1998 B5 / 1.G Hydraulic Changing And Bleeding Fluid Workshop Manual

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Brake hydraulic system,
bleeding and changing brake
fluid

WARNING!

Brake fluid is poisonous.

It must NEVER be removed by siphoning
with your mouth.
If brake fluid contacts skin or eyes, flush or
wash adequately to prevent irritation. Get
medical attention immediately if necessary.
Brake fluid must be disposed of properly in
compliance with environmental regulations.

CAUTION!
Do not allow brake fluid to mix with liquids
that contain mineral oils (e.g. motor oil,
cleaning agents). Mineral oils damage the
plugs and seals in the brake hydraulic
system.
Brake fluid must not be allowed to come into
contact with paintwork due to its caustic
effect.
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Note:

Only use new brake fluid conforming to US
standard FMVSS 116 DOT 4.
Genuine VW/Audi brake fluid conforms to this
specification.
Rinse off any spilled brake fluid using plenty of
water.
When the system is open do not work with
compressed air and do not move the vehicle.
During the final road test, make sure at least
one ABS-controlled braking operation is carried
out (normal pulsations must be felt at the brake
pedal).

Bleeding using US1116 brake bleeder

- Connect US1116 brake bleeder.

- Open bleeder screws in following sequence and
bleed brake calipers.

Bleeding sequence

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CAUTION!

Always dispose of used brake fluid properly.

On vehicles with manual transmission, the
clutch slave cylinder must also be flushed
out with new brake fluid.
On models with the electronic Stability
Program (ESP), note that the hydraulic pump
is actuated for 10 seconds using "Basic
Settings" function 04, display group 002
page 45
-49
.
Note the following when bleeding clutch
hydraulics:

- Connect US1116 but do not switch on yet.

- Open bleeder screw on clutch slave cylinder.

- Attach collector bottle hose.

- Switch on bleeder unit and allow approx. 100 cc
(6 oz.) of brake fluid to flow out of clutch slave
cylinder.

- Close bleeder screw.
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