209 Controls in detail
Driving systems
Distronic menu in the control system
In the Distronic menu you see the current
settings for Distronic. What appears in the
display depends on whether Distronic and
the distance warning function are turned
on or off.
Press buttonè orÿ repeatedly
until you see one of the following dis-
plays.
Warning!
G
An intermittent warning sounds and the
Distronic warning lampl in the instru-
ment cluster is illuminated if the Distronic
system calculates that the distance to the
vehicle ahead and your vehicle’s current
speed indicate that Distronic will not be ca-
pable of slowing the vehicle sufficiently to
maintain the preset following distance,
which creates a danger of a collision.
Immediately brake your vehicle to increase
the distance between your vehicle and the
vehicle in front of you. The warning sound is
intended as a final caution that you have not
interceded with your own braking inputs to
avoid a potentially dangerous situation. Do
not wait for the operation of the warning sig-
nal to intercede with your own braking, as
that will result in potentially dangerous
emergency braking which will not always re-
sult in an impact being avoided.
Tailgating increases the risk of an accident.
Warning!
G
Distronic brakes your vehicle with a maxi-
mum of 6.5 ft/s
2 (2 m/s
2). This corre-
sponds to about 20% of the maximum
deceleration ability of your vehicle.
Distronic brakes the vehicle in an effort to
restore the preset distance or to maintain
the speed. The brake pedal is automatically
applied as this happens which results in the
brake pedal moving.
Keep driver’s foot area clear at all times, in-
cluding the area under the brake pedal. Ob-
jects stored in this area may impair pedal
movement which could interfere with the
braking ability of the Distronic system.
Do not place your foot under the brake pedal
– your foot could become caught.
211 Controls in detail
Driving systems
Activating 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 79)
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 the ESP is switched offSetting 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 the cruise control lever in the
direction of arrow1 (
page 210) to
increase vehicle speed in increments
of 5 mph (Canada: 10 km/h)
The new speed is set.
The stored speed is displayed in the multi-
function display for approximately five sec-
onds (
page 210), and one or two
segments around the stored speed come
on on the speedometer (
page 208).
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 a 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.
213 Controls in detail
Driving systems
Deactivating Distronic
There are several ways to deactivate the
Distronic system:
Briefly tip the cruise control lever in the
direction of arrow3 (
page 210).
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 79) or you de-
activate the ESP
you move the gear selector lever into
positionN
A signal will sound. The
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.
214 Controls in detailDriving systems1Distance warning function on/off
switch
2Thumbwheel for setting distanceIncreasing distance
Increasing the distance setting causes Dis-
tronic to maintain a greater following dis-
tance to the vehicle ahead.
Turn thumbwheel2 towards¯.
Decreasing distance
Decreasing the distance setting causes
Distronic to maintain a shorter following
distance to the vehicle ahead.
Turn thumbwheel2 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 lampl also extinguishes.
215 Controls in detail
Driving systems
Activating
Press switch1.
The indicator lamp on the switch
comes on. A loudspeaker symbol ap-
pears in the multifunction display
(page 210).
Deactivating
Press switch1.
The indicator lamp on the switch goes
out.Driving with Distronic
This section describes a number of driving
situations where special precaution is re-
quired on the part of the driver. Be pre-
pared to brake in such situations which will
deactivate the Distronic system.
Warning!
G
If the Distronic 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.
Warning!
G
Distronic works to maintain the speed se-
lected by the driver unless a moving obsta-
cle proceeding directly ahead of it in the
same travel direction is detected (e.g. fol-
lowing another vehicle ahead of you at a dis-
tance set by Distronic). This means that:
Your vehicle can pass another vehicle
after you change lanes.
While in a sharp turn or if the vehicle in
front is in a sharp turn, Distronic could
lose sight of a vehicle traveling in front
of it, then your vehicle could accelerate
to the previously selected speed.
216 Controls in detailDriving 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, Dis-
tronic will switch off, and the message CURRENTLY UNAVAILABLE SEE OPER.
MANUAL
appears in the multifunction dis-
play.
For cleaning and care of the Distronic sen-
sor, see “Cleaning the Distronic* system
sensor cover” (
page 299).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.
Distronic regulates only the distance be-
tween your vehicle and those directly ahead
of it, but does not register stationary objects
in the road, e.g.:
a stopped vehicle in a traffic jam
a disabled vehicle
an oncoming vehicle
The driver must always be on the alert, ob-
serve all traffic and intercede as required by
steering or braking the vehicle.
Warning!
G
Distronic should not be used in snowy or icy
road conditions.
iIf the message
CURRENTLY UNAVAILABLE
SEE OPER. MANUAL
disappears during
driving and the last speed stored flash-
es for approximately five seconds, the
dirt (e.g. slush) has dissolved; Distronic
is again operational.
224 Controls in detailDriving systemsParktronic* (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 Park-
tronic system deactivates at speeds over
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
The 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 299).
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 that no persons or animals are in
the area in which you are maneuvering. You
could otherwise injure them.
225 Controls in detail
Driving systems
Range of the sensors
To function properly, the sensors must be
free of dirt, ice, snow and slush. Clean the
sensors regularly, being careful not to
scratch or damage the sensors.Front sensors
Rear sensorsMinimum distance
If the system detects an obstacle in this
range, all the warning lamps come on and
you hear a warning signal. If the obstacle is
closer than the minimum distance, the ac-
tual distance might no longer be indicated
by the system.
Center
approx. 40 in (100 cm)
Corners
approx. 24 in (60 cm)
Center
approx. 48 in (120 cm)
Corners
approx. 32 in (80 cm)
!During parking maneuvers, pay special
attention to objects located above or
below the height of the sensors (e.g.
planters or trailer hitches). The Park-
tronic system will not detect such ob-
jects at close range and damage to
your vehicle or the object may result.
Ultrasonic signals from outside sourc-
es (e.g. truck air brakes or jackham-
mers) may impair the operation of the
Parktronic system.
Center
approx. 8 in (20 cm)
Corners
approx. 6 in (15 cm)