Audi 243 Service Manual page 19

Pressure accumulator
The pressure accumulator allows the vehicle
level to be raised more rapidly with minimal
noise as the pressure accumulator is only
filled while the vehicle is in driving operation
and the compressor noise is less noticeable
(see air supply strategy).
Provided that there is sufficient pressure in
the pressure accumulator, vehicle level
raising can be performed without the
compressor.
Sufficient pressure means that before the
vehicle is raised there must be a pressure
difference of at least 3 bar between the
pressure accumulator and the air springs.
The pressure accumulator is made of
aluminium and has a storage volume of
approx. 6.5 l. The maximum operating
pressure is approx. 16 bar.
243_029
Pressure accumulator
Air supply strategy
At driving speeds of < 36 km/h air supply is
effected primarily by the pressure
accumulator (provided sufficient pressure is
available).
The pressure accumulator is only filled when
driving at speeds of 36 km/h and above.
At a driving speed of > 36 km/h the air supply
is primarily from the compressor.
This supply strategy ensures virtually
noiseless system operation and reduces the
current consumption.
Pressure connector
19