170Driving and operatingDrive systems
All-wheel drive
The All-wheel drive 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 up to a torque split of 50%
to 50%. Depending on the driving
conditions, i.e. steady state driving,
All wheel drive system transfers a
minimum amount of torque for fuel
efficiency. Additionally the torque
vectoring between the rear wheels is
distributed depending on the vehicle
dynamic and surface.
This is possible because the All wheel drive system operates with two
clutches, one on each side.
For optimum system performance,
the vehicle's tyres should not have
varying degrees of wear.If a service message is displayed in
the Driver Information Centre, the
system may have limited functionality
(or be completely disabled in some
cases, i.e. the vehicle switches to
Front-wheel drive). Seek the
assistance of a workshop.
Towing the vehicle 3 266.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 99.
Active emergency braking 3 193.
Antilock brake system Antilock brake system (ABS)
prevents the wheels from locking.
Driving and operating171ABS starts to regulate brake pressure
as soon as a wheel shows a tendency to lock. The vehicle remains
steerable, even during hard braking.
ABS control is made apparent
through a pulse in the brake pedal
and the noise of the regulation
process.
For optimum braking, keep the brake
pedal fully depressed throughout the
braking process, despite the fact that
the pedal is pulsating. Do not reduce
the pressure on the pedal.
After starting off, the system performs a self-test which may be audible.
Control indicator u 3 100.
Adaptive brake light During full braking, all three brake
lights flash for the duration of ABS
control.
Fault9 Warning
If there is a fault in the ABS, the
wheels may be liable to lock due
to braking that is heavier than
normal. The advantages of ABS are no longer available. During
hard braking, the vehicle can no longer be steered and may
swerve.
Have the cause of the fault remedied
by a workshop.
Parking brake
9 Warning
Before leaving the vehicle, check
parking brake status. Control
indicator m must illuminate
constantly.
Electric parking brake
Applying when vehicle is stationary
9 Warning
Pull switch m for a minimum of
one second until control indicator
m illuminates constantly and
electric parking brake is applied
3 99. The electric parking brake
operates automatically with
adequate force.
Before leaving the vehicle, check
the electric parking brake status.
Control indicator m 3 99.
Driving and operating173Operation of brake assist might
become apparent by a pulse in the
brake pedal and a greater resistance
when depressing the brake pedal.
Maintain steady pressure on the
brake pedal as long as full braking is
required. Maximum brake force is
automatically reduced when brake pedal is released.
Hill start assist The system helps prevent unintended
movement when driving away on
inclines.
When releasing the brake pedal after
stopping on an incline, brakes remain on for further two seconds. The
brakes release automatically as soon
as the vehicle begins to accelerate.Ride control systems
Traction Control system
The Traction Control system (TC) is a component of the Electronic Stability
Control (ESC).
TC improves driving stability when
necessary, regardless of the type of
road surface or tyre grip, by
preventing the drive wheels from
spinning.
As soon as the drive wheels starts to
spin, engine output is reduced and
the wheel spinning the most is braked
individually. This considerably
improves the driving stability of the
vehicle on slippery road surfaces.
TC is operational after each engine
start as soon as the control indicator
b extinguishes.
When TC operates b flashes.
9 Warning
Do not let this special safety
feature tempt you into taking risks
when driving.
Adapt speed to the road
conditions.
Control indicator b 3 100.
Deactivation
TC can be switched off when spinning of drive wheels is required: press t
briefly.
174Driving and operating
Control indicator k illuminates.
A status message appears in the
Driver Information Centre when TC is
deactivated.
When TC is deactivated, ESC
remains active but with higher control threshold.
TC is reactivated by pressing t again.
A status message pops up in the Driver Information Centre when TC is reactivated.
TC is also reactivated the next time
the ignition is switched on.
Fault
If there is a fault in the system the
control indicator b illuminates
continuously and a message appears
in the Driver Information Centre. The
system is not operational.
Have the cause of the fault remedied
by a workshop.
Electronic Stability Control Electronic Stability Control (ESC)
improves driving stability when
necessary, regardless of the type of
road surface or tyre grip.
As soon as the vehicle starts to
swerve (understeer/oversteer),
engine output is reduced and the wheels are braked individually.
ESC operates in combination with the
Traction Control system (TC). It
prevents the drive wheels from
spinning.
Torque distribution is a special
feature that allocates the torque to the drive wheels before the ESC
intervenes. When cornering, the
wheels on the inner curve are braked
individually. Additionally, engine
torque will be delivered to the drive wheel on the outer curve. This
reduces the tendency of
understeering and improves traction
when cornering fast.
ESC is operational after each engine
start as soon as the control indicator
b extinguishes.
When ESC operates b flashes.
9 Warning
Do not let this special safety
feature tempt you into taking risks
when driving.
Adapt speed to the road
conditions.
Control indicator b 3 100.
176Driving and operating● adaptive cruise control
● all-wheel drive
● engine sound enhancement
● instrument cluster theme
SPORT mode
The settings of the systems are
adjusted for a sportier driving style:
● Damping of shock absorbers is set up for increased handling andagility.
● The engine reacts more quickly to accelerator pedal changes.
● Steering support is sportier.
● Automatic transmission shift points optimised for sporty
driving.
● Adaptive cruise control is adjusted for a sportier driving
style.
● All-wheel drive supports active sporty driving of the vehicle.
● Engine sound enhancement intensifies interior engine sound
in a sporty manner.
● Cluster theme changes to sport.
TOUR modeTOUR mode adjusts the settings of
the systems for a comfortable driving
style.
● Damping of shock absorbers is adapted for increased driving
comfort.
● Steering efforts are reduced. ● Adaptive cruise control is adjusted for a more relaxed
driving style.
AUTO mode
All settings of the systems are preset
to standard values optimised for daily driving (default mode). This is the fully
adaptive mode, adjusting systems to
both comfort and sport settings
depending on driving style and driving
situation.
Adaptive drive mode control
Within each manually selected driving mode SPORT , TOUR or AUTO , Drive
Mode Control (DMC) detects and
analyses continuously the driving situation and the driver's driving style.
If necessary, DMC automatically
adjusts damping and steering for the
duration of the occuring situation.
Driving and operating179Control indicator m 3 103.
Switching on
Press m; control indicator m in
instrument cluster illuminates white.
Activation
Accelerate to the desired speed and
turn thumb wheel to SET/-, the
current speed is stored and
maintained. Control indicator m in
instrument cluster illuminates green.
On Mid- and Uplevel display m
illuminates green and set speed is
indicated. Accelerator pedal can be
released.
Vehicle speed can be increased by
depressing the accelerator pedal.
When the accelerator pedal is
released, the previously stored speed
is resumed.
Cruise control remains activated
while gearshifting.
Increase speed With cruise control active, hold thumb
wheel turned to RES/+ or briefly turn
to RES/+ repeatedly: speed
increases continuously or in small
increments.
Alternatively accelerate to the desired speed and store by turning to SET/-.Reduce speed
With cruise control active, hold thumb
wheel turned to SET/- or briefly turn to
SET/- repeatedly: speed decreases
continuously or in small increments.
Deactivation Press y; control indicator m in
instrument cluster illuminates white.
On Mid- or Uplevel display m
changes to white.
Cruise control is deactivated, but not
switched off. Last stored speed
remains in memory for later speed
resume.
Automatic deactivation: ● Vehicle speed is below approx. 30 km/h.
● Vehicle speed drops more than 25 km/h below the set speed.
● The brake pedal is depressed.
● The clutch pedal is depressed for
a few seconds.
● The selector lever is in N.
● Engine speed is in a very low range.
180Driving and operating● The Traction Control system orElectronic Stability Control is
operating.
● Parking brake is applied.
● Simultaneous pressing RES/+
and brake pedal deactivates
cruise control and will delete stored speed.
Resume stored speed
Turn thumb wheel to RES/+ at a
speed above 30 km/h. The stored
speed will be obtained.
Switching off
Press m, control indicator m in
instrument cluster extinguishes. The
stored speed is deleted.
Pressing L to activate the speed
limiter or switching off the ignition also switches off cruise control and
deletes the stored speed.
Speed limiter The speed limiter prevents the
vehicle exceeding a preset maximum
speed.The maximum speed can be set at
speeds above 25 km/h up to
200 km/h.
The driver can only accelerate up to
the preset speed. Deviations from the
limited speed may occur when driving
downhill.
The preset speed limit is displayed in
the Driver Information Centre when
the system is active.
Activation
Illustrations show different versions.
Press L, symbol L illuminates in the
Driver Information Centre.
If cruise control has been activated
before, it is switched off when speed
limiter is activated and the control
indicator m extinguishes.
Set speed limit
Accelerate to the desired speed and
briefly turn thumb wheel to SET/-: the
current speed is stored as maximum speed.
On Baselevel display L and the
speed limit is displayed.
Driving and operating181
On Mid- and Uplevel display L
changes to green.
Change speed limit With speed limiter active, hold or
briefly turn thumb wheel to RES/+ to
increase or SET/- to decrease the
desired maximum speed.
Exceeding the speed limit
When exceeding the limited speed without driver input, the speed will
flash in the Driver Information Centre
and a chime sounds during this
period.
In the event of an emergency, it is
possible to exceed the speed limit by
depressing the accelerator pedal
firmly nearly to the final point. In this
case no chime appears.
Release the accelerator pedal and
the speed limiter function is
reactivated once a speed lower than
the limit speed is obtained.
Deactivation Press y: speed limiter is deactivated
and the vehicle can be driven without
speed limit.
On Baselevel display the stored
limited speed is indicated in brackets.
On Mid- or Uplevel display L
changes to white.
Additionally, a corresponding
message appears.
Speed limiter is deactivated, but not
switched off. Last stored speed
remains in memory for later speed
resume.
Resume limit speed
Turn thumb wheel to RES/+. The
stored speed limit will be obtained
and is indicated without brackets in
the Driver Information Centre.
Switching off
Press L, the speed limit indication
extinguishes in the Driver Information Centre. The stored speed is deleted.
By pressing m to activate cruise
control or adaptive cruise control, speed limiter is also deactivated and
the stored speed is deleted.
By switching off the ignition, speed
limiter is also deactivated, but the
speed limit will be stored for next
speed limiter activation.
Adaptive cruise control
Adaptive cruise control is an
enhancement to conventional cruise control with the additional feature ofmaintaining a certain distance behind the vehicle ahead.