Audi A6 2005 User Manual

Running gear

Dampers

The Audi A6 Avant ´05 with aas also has
continuously adjustable rebound and compression
damping characteristics.
The front and rear axle dampers differ in respect of
their design from the dampers on the A8. The
electrically activated damping valve is located on
the exterior of the damper tube.
For this reason, and also because the dampers for
the A8 and A6 are sourced from different systems
suppliers, we refer to the suspension system on the
A6 as a Continuously Controlled Electronic
Suspension (CES) system.

Damping valve

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Separation of the rear axle springs and
dampers

The a dvantages of this configuration are an
optimised through-loading width and low boot
floor. A boot protects the complete air spring
against ingress of dirt. Due to the size of the air
springs, no additional air volume is required, which
is the case with the A8 D3. The boot can be replaced
by a service workshop.
A new aluminium trapezoidal link was developed for
the aas.

New aluminium trapezoidal link

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Air supply unit and solenoid valve block

The a ir supply unit and the solenoid valve block are
identical in design and function to those of the
allroad quattro and A8.
Both units are now mounted on a common bracket.

Air supply unit

Solenoid valve block

Mounting bracket

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Running gear

Ride heights

The modes implemented in the Audi A6 Avant ´05 are the same as in the A8. However, the ride heights are
different. The following conditions apply to the aas in the Audi A6 Avant ´05:
In "dynamic" mode, the car's ride height is lowered permanently by 15 mm compared to "automatic" mode.

When the "lift" mode is selected, the car body is raised by 15 mm compared to "automatic" mode.

The lowering of the suspension by 15 mm at motorway speeds in "automatic" mode is also implemented in
the Audi A6 Avant ´05. In the A6, there is no further reduction in ride height in "dynamic" mode, which is the
case in the A8.
The same conditions as on the A8 must be met in order to select and quit the various modes.

Reference

For further information, please refer
to the current operating instructions
and SSP 292.

aas modes in the Audi A6 Avant ´05

+15 mm

0 mm

"lift"

"comfort"

"dynamic"

"automatic"

-15 mm

0

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kph100 120

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System failure response

If the electrical damping valve is deenergised in
case of failure, a default damping force
characteristic takes effect. In this case, the damper
works like a conventional (non-controlled) damper.

Damper set-up

Damping valve deenergised

0

Rebound damping

Damping force (N)

aas with MMI Basic

The a as system is available in the Audi A6 Avant ´05
in combination with MMI and also, alternatively, in
combination with MMI Basic .

Speed m/s

Compression damping

2

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Running gear

New special tools

The following new special tools are used for aas in
the Audi A6 Avant ‘05:

T 40082/1-6 spring blocker for air springs

Due to the modified installation dimensions, the
spring blockers used for the A8 are unsuitable for
the A6. The advantage of using spring blockers on
the A6 front axle is that subsequent replacement of
the upper transverse rods is no longer needed.

T 40081 ramp

When the system is fully vented , the suspension
will be so low that, in case of unfavourable
dimensional tolerances, a car jack cannot be used.
In such case, the vehicle is driven up onto the 8 cm
high ramps. A car jack or an auto-hoist can then be
used.

A new test adapter with the type designation
VAS 1598/53 is used for the air spring control unit.

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adaptive cruise control (acc)

A new generation of the acc is used in the
Audi A6 Avant `05. This acc incorporates the
following modifications:

the exterior dimensions and weight of the acc unit
(sender and control unit) were substantially

Sensor / control unit in the A8 Sensor / control unit in the A6

reduced.

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The number of radar transceivers integrated into the sender was increased from three to four.
As a result, it was possible to increase the beam angle from 8 degrees to 16 degrees. By increasing the range
of the sensor, objects in the path of the vehicle can be detected earlier. The maximum range of the object
detector was increased to 180 metres from 150 metres. The acc functionality was significantly improved with
regard to lane-changing and winding country roads.

180 m

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Running gear

A heater was integrated into the bumper insert in front of the sender. It effectively prevents the build-up of
snow or ice on the surface of the bumper in front of the sender in wintry road conditions. As a result, higher
system availability is assured.
The heater is powered by the adaptive cruise control unit.
The heater is switched on and off in dependence on the ambient temperature.

The dynamic response of the vehicle in acc mode
under acceleration and under braking can now be
adapted to suit the driver's preferences by selecting
a driving program in addition to the distance setting
function. Three different driving modes can be
activated with the MMI (for detailed information,
refer to the current operating instructions).

Rough adjustment is no longer required for setting
the sender in the service workshop.

Car

adaptive cruise control

Gong volume medium

Driving mode

comfort

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ESP

The Bosch 8.0 ESP system previously featured in the A6 saloon will also be used in the Audi A6 Avant
`05.Several new functions will be implemented for use of the Bosch 8.0 ESP system in the Audi A6 Avant ´05.
To implement these auxiliary functions, the processing power of the ESP control unit was enhanced by
increasing the clock frequency to 60 MHz from 48 MHz. The new control unit will also be rolled out at the same
time in the A6 saloon.

Modified hydraulic brake assistant control for vehicles with acc

When the vehicle is travelling, acc continuously monitors objects in front of the vehicle within the range of the
radar sensor. The object detection function remains active even after the acc function has been deactivated by
the driver. The system has the capability to assess the "hazard potential" of a traffic situation. It does so by
evaluating a variety of parameters, including the number, position and speed of objects detected, the
distance to the objects detected, own vehicle speed etc.If a "potential hazard" is identified, the brake system is
prefilled and the cut-in threshold of the brake assistant is reduced.

Automatic activation of the hazard warning light system

If the brakes are applied hard, the hazard warning
light system is activated automatically to alert
traffic following on behind. On vehicles with the
Highline trim, the surfaces of the brake lights are
also enlarged, depending on the country
specification.

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Extended understeer correction

When a vehicle is understeering, it can be stabilised by braking the wheels on the inside of the corner.
However, if the cornering speed of the vehicle is too high to achieve the required curve radius, this action
alone will not be sufficient. In such case, all four wheels are braked and engine torque is simultaneously
reduced. A slightly higher brake pressure is applied to the inside rear wheel. In this way, the road speed of the
vehicle is reduced and the vehicle is stabilised.

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