150Driving 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 3 103.
Towing the vehicle 3 215.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 the 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 92.
Antilock brake system
Antilock brake system (ABS)
prevents the wheels from locking.
Vehicle care2113. Ensure the jack is correctlypositioned under the relevant
vehicle jacking point.
Depending on the equipment, first remove the covers from the
jacking points.
4. Set the jack to the necessary height. Position it directly below
the jacking point in a manner that prevents it from slipping.
Attach wheel wrench and with the
jack correctly aligned rotate wheel wrench until wheel is clear of the
ground.
5. Unscrew the wheel nuts.
6. Change the wheel. Spare wheel 3 212.
7. Screw on the wheel nuts.
8. Lower the vehicle and remove jack.
9. Install the wheel wrench ensuring that it locates securely and tighten
each nut in a crosswise
sequence. Tightening torque is
140 Nm.
10. Align the valve hole in the wheel cover with the tyre valve before
installing.
Install wheel nut caps.
Install centre cap on alloy wheels.
11. Install vehicle jacking point cover on versions with sill panelling.
12. Stow the replaced wheel 3 212
and the vehicle tools 3 199.
13. Check the tyre pressure of the installed tyre and the wheel nut
torque as soon as possible.
Have the defective tyre renewed or
repaired as soon as possible.Jacking position for lifting platform
Rear arm position of the lifting
platform centrically under the recess
of the sill.