218 Controls in detailDriving systems
Driving systemsThe driving systems of your vehicle are de-
scribed on the following pages:
Cruise control and Distronic*, with
which the vehicle can maintain a preset
speed
Parktronic*, which serves as a parking
assistant.
For information on the BAS, ABS, and ESP
driving systems, see “Driving safety sys-
tems” (
page 76).
Cruise control
Cruise control automatically maintains the
speed you set for your vehicle.
Use of cruise control is recommended for
driving at a constant speed for extended
periods of time. You can set or resume
cruise control at any speed over 20 mph
(30 km/h).
The cruise control function is operated by
means of the cruise control lever.
The cruise control lever is the uppermost
lever found on the left-hand side of the
steering column (
page 20).
Warning!
G
Cruise control is a convenience system de-
signed to assist the driver during vehicle op-
eration. The driver is and must remain at all
times responsible for the vehicle speed and
for safe brake operation.
Only use cruise control if the road, traffic
and weather conditions make it advisable to
travel at a steady speed.
The use of cruise control can be danger-
ous on winding roads or in heavy traffic
because conditions do not allow safe
driving at a steady speed.
The use of cruise control can be danger-
ous on slippery roads. Rapid changes in
tire traction can result in wheel spin and
loss of control.
Deactivate cruise control when driving
in fog.
The “Resume” function should only be oper-
ated if the driver is fully aware of the previ-
ously set speed and wishes to resume this
particular preset speed.
221 Controls in detail
Driving systems
Distronic*
When activated, the Distronic adaptive
cruise control system increases the driving
convenience afforded by the cruise control
during travel on expressways and other
major roads.
If the Distronic distance sensor detects
a slower moving vehicle directly ahead,
your vehicle speed will be reduced so
that you follow that vehicle at a preset
distance.
If there is no vehicle directly ahead of
you, Distronic will function in the same
way as cruise control (
page 218).
Warning!
G
Distronic adaptive cruise control is no sub-
stitute for active driving involvement. It does
not react to stationary objects, nor recog-
nize or predict the curvature and lane layout
or the movement of vehicles ahead. Distro-
nic can only apply a maximum of 20% of the
vehicle’s braking power.
It is the driver’s responsibility at all times to
be attentive to traffic and road conditions
and to provide the steering, braking and oth-
er driving inputs necessary to retain control
of the vehicle.Warning!
G
Distronic is a convenience system. Its speed
adjustment reduction capability is intended
to make cruise control more effective and
usable when traffic speeds vary. However, it
is not intended to, nor does it, replace the
need for extreme care. The responsibility for
the vehicle speed and the distance to the ve-
hicle ahead, including most importantly
brake operation to assure safe stopping dis-
tance, always rests with the driver.
Distronic cannot take street and traffic con-
ditions into account.
Warning!
G
Distronic requires familiarity with its opera-
tional characteristics. We strongly recom-
mend that you review the following
information carefully before operating the
system.iFor operation in the USA only: This de-
vice complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
This device may not cause harmful
interference, and
this device must accept any inter-
ference received, including interfer-
ence that may cause undesired
operation.
Any unauthorized modification to this
device could void the user’s authority
to operate the equipment.
222 Controls in detailDriving systemsWarning!
G
Distronic cannot take street and traffic con-
ditions into account. Only use Distronic if
the road, traffic and weather conditions
make it advisable to travel at a steady
speed.Warning!
G
Use of Distronic can be dangerous on slip-
pery roads. Rapid changes in tire traction
can result in wheel spin and loss of control.
Distronic does not act upon adverse sight
distance conditions. Do not use Distronic
during conditions of fog and heavy rain,
snow or sleet.
Warning!
G
Close attention to road and traffic condi-
tions is imperative at all times, regardless of
whether or not Distronic is activated.
Use of Distronic can be dangerous on wind-
ing roads or in heavy traffic because condi-
tions do not allow safe driving at a steady
speed.
Distronic will not react to stationary objects
in the roadway (e.g. a stopped vehicle in a
traffic jam or a disabled vehicle). Distronic
will also not respond to oncoming vehicles.
Switch off Distronic:
when changing from the left to the right
lane if vehicles are moving more slowly
in the left lane
when entering a turn lane or highway off
ramp
in complex driving situations, such as in
highway construction zones
In these situations, Distronic will continue to
maintain the set speed unless deactivated.
Distronic is designed and intended only to
maintain a set speed and keep a set dis-
tance from moving objects in front of it.Warning!
G
The “Resume” function should only be oper-
ated if the driver is fully aware of the previ-
ously set speed and wishes to resume this
particular preset speed.
226 Controls in detailDriving systemsActivating Distronic
You can activate Distronic if
you are driving between 25 mph
(40 km/h) and 110 mph (180 km/h)
the ESP is activated (
page 78)
If Distronic has not been activated after
pressing the cruise control lever you will
see the message
---
in the multifunction
display.
In the following cases you cannot activate
Distronic:
up to two minutes after starting the en-
gine.
when you brake.
if you have set the parking brake.
if the gear selector lever is in
positionP, R or N.
if ESP is switched off.Setting the current speed
Accelerate or decelerate to the desired
speed.
Briefly lift or depress the cruise control
lever.
Distronic is activated and the current
speed is set.
Remove your foot from the accelerator
pedal.Setting a higher speed
Briefly tip cruise control lever in the di-
rection of arrow1 (
page 225) to in-
crease vehicle speed in increments of
5 mph (Canada: 10 km/h).
The new speed is set.
The stored speed is displayed in the
multifunction display for approximately
five seconds (
page 225), and one or
two segments around the stored speed
come on, on the speedometer
(
page 223).
iIf you do not take your foot off of the
accelerator completely, the following
message will appear in the multifunc-
tion display: Distronic override
.
Distronic will not work to maintain the
distance to slower moving vehicles in
front of you. Your vehicle speed will
then be determined only by the accel-
erator pedal position.
iDepressing the accelerator pedal does
not deactivate Distronic. After brief ac-
celeration (e.g. for passing), the cruise
control will resume the last speed set.
228 Controls in detailDriving systemsDeactivating Distronic
There are several ways to deactivate the
Distronic system:
Briefly tip cruise control lever in the di-
rection of arrow3 (
page 225).
or
Step on the brake pedal.
Distronic will be deactivated. The last
speed set will be stored into memory.Distronic deactivates automatically when
you set the parking brake
you drive slower than 25 mph
(40 km/h)
the ESP is active (
page 78) or you de-
activate the ESP
you move the gear selector lever into
positionN.
A si gnal wi ll s ound. T he
Distronic off
message appears in the multifunction
display for approximately five seconds.Setting the following distance in
Distronic
You can set the specified following dis-
tance for Distronic by varying the time set-
ting between 1.0 and 2.0 seconds. Using
this time setting and the current speed of
your vehicle, Distronic calculates and sets
the required following distance to the vehi-
cle ahead. The set distance will be shown
in the multifunction display field.
The thumbwheel for making the time set-
ting is located on the lower section of the
center console.
iThe following message will appear in
the multifunction display for approxi-
mately five seconds:
Distronic off
.
The last stored speed is deleted when
you turn off the engine.
Warning!
G
Distronic switches off and releases the
brakes when the vehicle decelerates below
the minimum speed of approximately
25 mph ( 40 km / h) by operation of the sys-
tem. At that time the driver must apply the
brakes in order to reduce vehicle speed fur-
ther or bring it to a stop.
Warning!
G
It is up to the driver to exercise discretion to
select the appropriate setting given road
conditions, traffic, driver’s preferred driving
style and applicable laws and driving recom-
mendations for safe following distance.
229 Controls in detail
Driving systems
1Distance warning function on/off
switch
2Control lamp
3Thumbwheel for setting distance
Increasing distance
Increasing the distance setting causes
Distronic to maintain a greater following
distance to the vehicle ahead.
Turn thumbwheel3 towards¯.Decreasing distance
Decreasing the distance setting causes
Distronic to maintain a shorter following
distance to the vehicle ahead.
Turn thumbwheel3 towards®.
Distance warning function
When Distronic is deactivated, this func-
tion will continue to warn you when recog-
nizing a stationary obstacle or a slower
vehicle moving in the vehicle’s path and
the danger of a collision exists:
The distance warning lampl in the
instrument cluster comes on
An intermittent warning sounds.
If these warnings are issued, you must
brake manually to maintain a safe distance
and avoid a collision with the vehicle
ahead.
When pressing the brake pedal, the warn-
ing sound stops. The warning sound also
stops when the distance to the vehicle ahead is sufficient again without applying
the brake pedal. In this case the distance
warning lamp also extinguishes.
Warning!
G
If the distance warning lampl in the in-
strument cluster comes on while driving
and/or an intermittent warning sounds, im-
mediate attention on the part of the driver is
required.
As required by the traffic situation, apply the
brakes and navigate around a possible ob-
stacle. However, do not drive by relying on
the distance warning function, as this will re-
sult in an emergency braking application.
Especially depending on road surface condi-
tions and driver reaction, this will not always
enable you to avoid a collision.iComplex driving situations are not al-
ways fully recognized by Distronic. This
could result in wrong or missing dis-
tance warnings.
231 Controls in detail
Driving systems
The most likely cause for a malfunctioning
system is a dirty sensor (located behind
the hood grille), especially at times of snow
and ice or heavy rain. In such a case,
Distronic will switch off, and the message Distronic
Currently unavailable!
see oper. manual appears in the multifunction display.
For cleaning and care of the Distronic sen-
sor, see “Cleaning the Distronic* system
sensor cover” (
page 301).Turns and bends
In turns or bends, Distronic may not detect
a moving vehicle in front, or it may detect
one too soon. This may cause your vehicle
to brake late or unexpectedly.
iIf the messageDistronic
Currently unavailable!
see oper. manualdisappears during driving and the last
speed stored flashes for approximately
five seconds, the dirt (e.g. slush) has
dissolved; Distronic works again.
233 Controls in detail
Driving systems
Parktronic (Parking assist)*
The Parktronic system is an electronic aid
designed to assist the driver during park-
ing maneuvers. It visually and audibly indi-
cates the relative distance between the
vehicle and an obstacle.
The Parktronic system is automatically ac-
tivated when you switch on the ignition
and release the parking brake. The
Parktronic system deactivates at speeds
over approximately 11 mph (18 km/h). At
lower speeds the Parktronic system turns
on again.The Parktronic system monitors the sur-
roundings of your vehicle with six sensors
in the front bumper and four sensors in the
rear bumper.
1Sensors in the front bumperWarning!
G
Parktronic is a supplemental system. It is
not intended to, nor does it replace, the
need for extreme care. The responsibility
during parking and other critical maneuvers
always rests with the driver.
Special attention must be paid to objects
with smooth surfaces or low silhouettes
(e.g. trailer couplings, painted posts or road
curbs). Such objects may not be detected by
the system and can damage the vehicle.
The operational function of the Parktronic
system can be affected by dirty sensors, es-
pecially at times of snow and ice, see
“Cleaning the Parktronic* system sensors”
(page 301).
Interference caused by other ultrasonic sig-
nals (e.g. working jackhammers or the air
brakes of trucks) can cause the system to
send erratic indications, and should be tak-
en into consideration.
Warning!
G
Make sure no persons or animals are in the
area in which you are maneuvering. You
could otherwise injure them.