41
Air suspension strut design
In the case of the quattro suspension strut,
the connection/seal between the air spring
(piston) and the damper is made via a double-
sealed bayonet connector.
The bayonet connector must be absolutely
clean and is greased before assembly with a
special lubricant (see Workshop Manual).
It is assembled by pushing on and rotating
the air spring.
Always check for leaks on the O-ring
seals at the marked positions. The
sealing surfaces must be clean, free
from corrosion and pitting (aluminium
parts) and greased as required (see
Workshop Manual).
242_009 O-ring
2 O rings
Bayonet connectorLocking cap
57
The interfaces
The driving speed signal
(a square wave signal processed by the dash
panel insert, the frequency of which changes
analogously to the speed)
is required in the evaluation of the driving
condition (stationary/driving mode) and
thereby for the selection of the control
criteria (see ÒControl conceptÓ). 1 wheel revolution
Signal T.15 ...
... is used for the evaluation of the system
status, run-on, stationary, driving and sleep
modes.
Signal T. 50 ...
... signals the control of the starter and is
used to switch off the compressor during the
starting process.
If a low position is detected after a wake-up
pulse, the compressor is actuated
immediately in order to allow the vehicle to
drive off as quickly as possible.
The compressor is switched off during the
starting process to protect the battery and
ensure starting performance. The door switch signal...
... is an earth signal from the control unit for
central locking. It signals that the door or
boot lid/tailgate is open.
... serves as the Òwake-up pulseÓ for the
transition from sleep mode to run-on mode
(see ÒControl conceptÓ).
Driving speed signal (4 pulses)
Signal from speedometer sender (reed contact)
We speak of run-on mode even if the
system is currently in Òrun-upÓ mode
(after a wake-up pulse before
commencing driving).
198_069
