ar4231p6002rt

Remove/install BAS diaphragm travel sensor

Type ar · topic 42.31 · version 0200 · 2010-12-02

Applies to: MODEL 251

Where it sits

Function group 2 Chassis › 42 Brakes - hydraulic and mechanical systems › 42.31 Brake assist (BAS) — Series 251

EinPAS 26 Active safety system › 26.20 Braking/traction control › 26.20.12 Sensor/switch/wiring harness — Series 251

AR42.31-P-6002RT

Remove/install BAS diaphragm travel sensor

30.11.10

MODEL 251

Remove/install BAS diaphragm travel sensor

P42.31-2068-09

1 Water drain pipe

2 Screw

3 Screw

4 Nuts

5 Cover

6 Bracket

7 Electrical connector

8 Retaining ring

9 BAS diaphragm travel sensor

10 Brake booster

11 O-ring

Modification notes

1.9.10

"Perform brake test on test bench" reference changed

Test sequence augmented/revised

Remove/install

1

Release vacuum in BAS brake booster

The diaphragm travel sensor sealing ring may be sucked into the brake booster if vacuum is present.

If this is the case the brake booster must be replaced.

Reduce vacuum by depressing the brake pedal several times.

2

Open engine hood and raise to vertical position

AR88.40-P-1000RT

3

Unclip water drain pipe (1)

Installation: Make sure that the water drain pipe (1) is seated correctly.

4

Remove bolt (2)

5

Remove bolt (3)

6

Unscrew nuts (4)

7

Lift up cover (5)

8

Remove bracket (6)

9

Disconnect electrical connector (7) from BAS diaphragm travel sensor (9)

10

Lift circlip (8) and pull BAS diaphragm travel sensor (9) out of the brake booster (10) (arrow B)

In order to prevent a permanent set of the circlip (8), lift the circlip (8) by a maximum of 10 mm

Use a suitable tool e.g.an angled scriber (arrow A).

Installation: Coat liquid lubricant on the BAS diaphragm travel sensor (9) at the front.

Installation: Install new O-ring (11).

Installation: Check and ensure correct latching of the circlip (8) in the groove of the BAS diaphragm travel sensor (9) and brake booster (10).

Lubricant paste

*BR00.45-Z-1002-06A

11

Install in the reverse order

12

Read out and erase the fault memory using Star Diagnosis

AD00.00-P-2000-04A

Danger!

Risk of death caused by limbs being caught or crushed by rotating parts when performing tests on the brake test stand

Never leave the vehicle unattended on the rollers except in an emergency. Ensure that no one is under the vehicle or near rotating parts during testing. In case of emergency, use the EMERGENCY STOP switch to shut down test stand.

AS42.00-Z-0001-01A

13

Carry out brake test on the test stand

AP42.00-P-4290BA

Repair materials

Number

Designation

Order number

BR00.45-Z-1002-06A

Lubricating paste, rubber parts 2.5 kg, DB supply specification 6867.00

A 000 989 01 60

Referenced documents