Check compressed-air system for leaks

AR42.60-G-0600UG

Check compressed-air system for leaks

04.03.2020

Model

405.090/104/105/110/125/202/222

Up to vehicle identification end number 253218

1

Test connection (rear axle supply brake circuit)

As of vehicle identification end number 253219

1

Test connection (rear axle supply brake circuit)

2

Test connection (front axle supply brake circuit)

6

Test connection (at ABS regulating valve)

 Warning

Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.

Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.

AS00.00-Z-0005-01A



Check

1

Park vehicle on a level surface and secure with chocks to prevent it from rolling away

2

Connect test cables of test kit to test connections (1, 2, 6).

 Test kit

*360589002100

3

Release parking brake.

4

Switch on ignition.

 Do not start engine.

5

Read off pressure in rear axle brake circuit supplies and in front axle brake circuit supplies on test kit and compare with pressure regulator cut-in pressure.

Vehicles up to vehicle identification end number 253218Pressure regulator cut-in pressure

*BE42.10-N-1002-10E

Vehicles as of vehicle identification end number 253219Pressure regulator cut-in pressure

*BE42.60-N-1015-03U

If the pressure is over the pressure regulator cut-in pressure.



Lower pressure on test kit below the respective pressure regulator cut-in pressure.

6

Start the engine and completely fill compressed-air system at idle speed.

 The pressure regulator in the air drier with integrated pressure regulator, or the pressure regulator in the electronic air-processing unit (EAPU) switches off with an audible shutdown sound after reaching the shutoff pressure.

7

Stop the engine and switch off the ignition.

8

After 2 minutes using the brake pedal jack on the service brake, introduce a partial braking with a pressure of 3.5  bar, measured at test connection (6).

 Depending on the technical equipment of the vehicle, a pressure drop can occur after switching off the engine and the ignition, caused by auxiliary consumers.
In order not to evaluate this pressure drop at the same time, a waiting time of 2 minutes must be maintained.
Avoid getting in and out of the vehicle during the test.

 Brake pedal jack

*000589183100

9

After 1 min, read off pressure at test connections (1, 2) on test kit.

 The waiting time is required in order not to evaluate the pressure drops within the compressed-air components at the same time.
The pressure reduction can be caused by a compressed-air components internal setting process done for technical reasons.

10

After a further 3 mins, read off pressure at test connections (1, 2) on test kit again.

Vehicles up to vehicle identification end number 253218Permissible pressure loss for operation of service brake with 3.5 bar (measuring period 3 minutes)

*BE42.10-N-1005-10E

Vehicles as of vehicle identification end number 253219Permissible pressure loss for operation of service brake with 3.5 bar (measuring period 3 minutes)

*BE42.60-N-1012-03U

If the pressure loss is higher.



Identify and eliminate leakage.

11

Engage parking brake.

12

Remove brake pedal jack.

13

Remove test cables of test kit from test connections (1, 2, 6).

Test and adjustment values for service brake

Number

Designation

Model 405.090/104/105/110/125/202/222 up to 253218

BE42.10-N-1002-10E

Pressure regulator cut-in pressure

bar

15,8

Test and adjustment values for service brake

Number

Designation

Model 405.090/104/105/110/125/202/222 up to 253218

BE42.10-N-1005-10E

Permissible pressure loss for operation of service brake with 3.5 bar (measuring period 3 minutes)

bar

0,4

Test and adjustment values for Electronic Air-Processing Unit (EAPU)

Number

Designation

Model 405.090/104

Model 405.105/110/125/202/222

BE42.60-N-1012-03U

Permissible pressure loss for operation of service brake with 3.5 bar (measuring period 3 minutes)

bar

 0,4

 0,4

Test and adjustment values for Electronic Air-Processing Unit (EAPU)

Number

Designation

Model 405.090/104

Model 405.105/110/125/202/222

BE42.60-N-1015-03U

Pressure regulator cut-in pressure

when driving

bar

11,7...12,3

11,7...12,3

with the vehicle stationary

bar

9,7...11,3

9,7...11,3

with external filling

bar

9,0...11,3

9,0...11,3