132Driving and operatingDrive systems
All-wheel drive The All-Wheel Drive (AWD) system
enhances driving characteristics and
stability, and helps to achieve the best possible driveability regardless of
ground surface. The system is always
active and cannot be deactivated.
The torque is distributed steplessly
between the wheels of the front and rear axle, depending on the driving
conditions. Additionally the torque
between the rear wheels is distributed
depending on the surface.
For optimum system performance,
the vehicle's tyres should not have
varying degrees of wear.
When using a temporary spare
wheel, the AWD system is
automatically disabled.
The AWD system will also be
temporarily disabled to protect the
system from overheating if there is
excessive wheel spin. When the
system cools down, AWD will be
restored.The deactivation of the AWD system
will be indicated by a message on the
Driver Information Centre.
If a service message or warning
code S73 is displayed on the Driver Information Centre, there is a
malfunction in the AWD system. Seek the assistance of a workshop.
Vehicle messages 3 95, Towing the
vehicle 3 196.Brakes
The brake system comprises two
independent brake circuits.
If a brake circuit fails, the vehicle can
still be braked using the other brake
circuit. However, braking effect is
achieved only when the brake pedal
is depressed firmly. Considerably
more force is needed for this. The
braking distance is extended. Seek the assistance of a workshop before
continuing your journey.
When the engine is not running, the
support of the brake servo unit
disappears once the brake pedal has been depressed once or twice.
Braking effect is not reduced, but
braking requires significantly greater
force. It is especially important to bear this in mind when being towed.
Control indicator R 3 85.
Antilock brake system
Antilock brake system (ABS)
prevents the wheels from locking.
