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Self-levelling suspension, A6
Other features of the
control concept
Lifting platform mode
System behaviour:
If the vehicle is raised on a lifting platform the
system will react in the same manner as for a
level increase, by discharging the air spring
pressure.
The vehicle body would normally lower at this
point. Lowering ceases once the reference
level is reached.
As, however, the reference level is not
reached when a vehicle is raised on a lifting
platform, the air spring pressure would
continue to discharge down to the residual
supporting pressure. To prevent this
happening, the control system incorporates a
lifting platform mode.
This evaluates the level signal during the
discharge process and recognises a lifting
platform (no lowering, despite discharge),
whereby the system switches to lifting
platform mode.
When it recognises a lifting platform,
discharge stops and lowering ceases.
The system exits lifting platform mode by
means of the evaluation of further input
signals.It is normal for the rear axle to sink
after placing the vehicle onto the lifting
platform as a certain amount of time
will elapse before the system switches
to lifting platform mode and will
therefore release some pressure.
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