37 22 540 Replacing Air Supply Unit

37 22 540 Replacing air supply unit





Important!
Risk of injury!
Drain the air spring system before carrying out any work on the air supply unit, air pipes and air spring struts! Danger of injury if this instruction is not complied with!
Risk of damage!
Extreme cleanliness must be ensured in the connection area of the pipes during removal and installation. Even the smallest of dirt particles can cause leakage in the air spring system.

Note:
Read and comply with notes on air spring system.





Necessary preliminary tasks:
^ Deactivating air spring system:
- Raise vehicle on lifting platform.
- Remove ignition key

- Pull out fuse for air spring system in luggage compartment at rear right





Important!
Do not kink, twist or crush lines.





Unscrew nuts (1).

Release screws (2).

Lever out expander rivets (3) and remove panel (4).
- Unlock plug connections (1/2) and disconnect.





Carefully slacken banjo bolt (3) and (4) until the sound of escaping air can be heard
Note: Wait roughly 2 minutes until the pressure on the left side and/or right side of the air spring system is completely reduced (hissing sound stops).
Line (3), air spring strut, left: Blue
Line (4), air spring strut, right: Red
- Only fully release banjo bolt(s) after pressure has completely reduced





Installation:
- Replacement: Remove and dispose of screw connections on new air supply unit!
Reuse screw connections on lines.
- Check banjo bolts for dirt, clean if necessary.
- Carefully screw in banjo bolts by hand to avoid damaging the plastic threads and with it the air supply unit.
Tightening torque 37 12 1AZ.





Unfasten plug connector (1) and disconnect.

Disconnect ventilation line (2).

Release nuts (3) and remove air supply unit.

Tightening torque 37 22 1AZ.





Activating and filling air spring system:
- Insert fuse in corresponding slot in fuse box
- Set vehicle down on its wheels
- Start engine
- Air spring system is automatically filled