AUDI A4 1996 B5 / 1.G ESP Service Workshop Manual

45-41


Electronic Stability Program
(ESP) hydraulic unit, servicing The tightening torque for all brake lines on the Audi
A4 is 15 Nm (11 ft lb).
1 -
ESP hydraulic unit
Always replace complete unit
2 -
Nut 12 Nm (9 ft lb)
3 -
Bolt and washer assembly 9 Nm (80 in lb)3x
4 -
Resilient bushing 2x
5 -
ESP hydraulic pump -V156- Assembly includes brake pressure sensor
6 -
Resilient pad Pad stud mount to hydraulic pump: 2 Nm
(18 in lb)
7 -
Vehicle body
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45-42


8 -
Nut
9 Nm (80 in lb)
9 -
Bracket
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45-43


1 -
Left-front brake line
2 -
Right-front brake line
3 -
Brake line
ESP hydraulic pump to brake master
cylinder primary piston circuit
4 -
Fixture
5 -
Connection fitting
6 -
Hose clamp
7 -
Hose
8 -
Hose clamp
9 -
Suction line
10 -
Brake line To ESP hydraulic pump
11 -
Brake line To brake master cylinder secondary piston
circuit
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45-44

Electronic Stability Program (ESP)
hydraulic pump, removing and installing


Special tools and equipment

Sealing plugs from repair kit Part No. 1H0 698
311A
VAG1551 or VAG1552 scan tool
US1116 brake bleeder

CAUTION!

Part numbers are listed here for reference
only. Always check with your Parts
department for the latest information.

Component location
The ESP hydraulic pump is located on the left side of the engine
compartment below the hydraulic control unit.
Removing
Note:
Switch off ignition before removal or installation work. If the vehicle is - Place vehicle on lift.
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equipped with a coded radio determine the correct coding before
disconnecting the battery.
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45-45

- Raise vehicle.

- Remove left-front wheel.

- Remove left-front wheelhouse liner.

- Disconnect electrical harness connectors (arrows).
- Remove cover on hydraulic reservoir.

- Unclip attachment strip at bracket.
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45-46


- Remove mounting screws (arrows) and swing coolant expansion tank
to side.
Tightening torque: 6 Nm (53 in lb)

Pay attention to bottom mounting (rubber grommet) when installing. - Remove bolts -1- for hydraulic fluid reservoir and swing to side.
Tightening torque: 10 Nm (7 ft lb)
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) hydraulic unit, servicin
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e=re
pair&id=AUDI.B5.SU03.45.5

45-47

Note:
Protect the engine compartment from brake fluid
which flows out.

CAUTION!

Brake fluid must not be allowed to come into
contact with paintwork because of its caustic
effect.

- Loosen hose clamp on suction hose -1- and detach.
- Disconnect brake lines -3- and -4-.
- Seal brake lines and threaded holes with plugs from repair kit Part No.
1H0 698 311A.
- Unclip brake lines from fixture.
- Remove nut -2-.
- Remove bolts for mounting bracket page 45
-41
, item 3 .
- Working from engine compartment, lift bracket together with hydraulic
pump approx. 30 mm (1 3/16 in) and remove.
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45-48

Installing

Note:
When installing, pay particular attention to the
following points.

Only remove the sealing plugs on the new
hydraulic control unit when the corresponding
brake line is about to be installed.
If the sealing plugs are removed too early the
brake fluid can escape.

- Bleed brake system page 47
-23
.

Bleeding brake system using US1116 brake
bleeder

- Connect US1116 brake bleeder.

- Open bleeder screws in the following sequence
and bleed brake calipers (assist with pedal
pressure, if necessary).

Bleeding sequence

2 - Left-rear brake caliper
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3 - Right-front brake caliper

1 - Right-rear brake caliper

4 - Left-front brake caliper
Pa
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yp
e=re
pair&id=AUDI.B5.SU03.45.5