217 Controls in detail
Driving systems
Distronic*
When activated, the Distronic adaptive
cruise control system increases 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 214).
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.
Distronic 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 road, traffic, and weather
conditions and to provide the steering, brak-
ing and other driving inputs necessary to re-
tain 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. It is not
however, intended to, nor does it, replace
the need for extreme care. The responsibili-
ty for the vehicle speed and the distance to
the vehicle ahead, including most impor-
tantly brake operation to assure safe stop-
ping distance, always remains 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.
iUSA only: This device has been approved by
the FCC as a “Vehicular Radar System”. The ra-
dar sensor is intended for use in an automotive
radar system only. Removal, tampering, or alter-
ing of the device will void any warranties, and is
not permitted by the FCC. Do not tamper with,
alter, or use in any non-approved way.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.
228 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 Operator’s Manual
appears in the multifunction display.
For cleaning and care of the Distronic sen-
sor, see “Cleaning the Distronic* system
sensor cover” (
page 337).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,
observe 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
DISTRONIC
Currently Unavailable
See Operator’s Manual
disappears during driving and the last speed
stored flashes for approximately 5 seconds, the
dirt (e.g. slush) has dissolved; Distronic works
again.
234 Controls in detail
Driving systems
Parktronic system (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
activated when you switch on the ignition,
release the parking brake, and placed the
gear selector lever in positionD, R,orN.
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 also deactivates
when you place the gear selector lever in
positionP or depress the parking brake
pedal.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 bumper
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, see
“Cleaning the Parktronic* system sensors”
(
page 337).
Warning!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 remains 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,
especially at times of snow and ice, see
“Cleaning the Parktronic* system sensors”
(
page 337).
Interference caused by other ultrasonic sig-
nals (e.g. working jackhammers, car wash or
the air brakes of trucks) can cause the sys-
tem to send erratic indications, and should
be taken into consideration.
Warning!G
Make sure no persons or animals are in the
area in which you are maneuvering. You
could otherwise injure them.
235 Controls in detail
Driving systems
Front sensors
Rear sensorsMinimum distance
If the system detects an obstacle in this
range, all the distance warning segments
illuminate and you hear a warning signal. If
the obstacle is closer than the minimum
distance, the actual distance might no
longer be indicated by the system.
Centerapprox. 40 in (100 cm)
Cornersapprox. 24 in (60 cm)
Centerapprox. 48 in (120 cm)
Cornersapprox. 32 in (80 cm)
!During parking maneuvers, pay special at-
tention to objects located above or below the
height of the sensors (e.g. planters or trailer
hitches). The Parktronic system will not detect
such objects at close range and damage to your
vehicle or the object may result.
Ultrasonic signals from outside sources (e.g.
truck air brakes, car wash or jackhammers) may
impair the operation of the Parktronic system.
Centerapprox. 8in (20cm)
Cornersapprox. 6in (15cm)
236 Controls in detail
Driving systems
Warning indicators
Visual signals indicate to the driver the rel-
ative distance between the sensors and an
obstacle. The warning indicator for the
front area is located above the center air
vents in the dashboard. The warning indi-
cator for the rear area is integrated in the
rear trim.
Front area warning indicator
1Left side of the vehicle
2Right side of the vehicle
3Readiness indicatorsEach warning indicator is divided into five
yellow and two red segments for either
side of the vehicle. The Parktronic system
is operational when yellow readiness
indicators3 are illuminated.
The position of the gear selector lever
determines which warning indicators will
be activated.
As your vehicle approaches an object, one
or more segments will come on, depending
on the distance. When the seventh seg-
ment illuminates, you have reached the
minimum distance.
Front area: An intermittent acoustic
warning will sound as the first red
distance segment illuminates and a
constant acoustic warning lasting a
maximum of 2 seconds will sound for
the second red distance segment. The
signal is canceled when the gear selec-
tor lever is placed in positionP or the
parking brake is activated.
Rear area: An intermittent acoustic
warning will sound as the first red
distance segment illuminates and a
constant acoustic warning lasting a
maximum of 2 seconds will sound for
the second red distance segment. The
signal is canceled when the gear selec-
tor lever is placed in positionD, P or
the parking brake is activated.Gear selector
lever positionWarning indicator
DFront area activated
R or NFront and rear area
activated
PNeither activated
310 Operation
Tires and wheels
Tire pressure inquiries are made using the
multifunction display. The present inflation
pressures are displayed only after a few
minutes travel time.
Switch on the ignition (page 38).
Press thej or kbutton until
the current inflation pressures for each
tire appear in the multifunction display.
iPossible differences between the readings
of a tire pressure gauge of an air hose, e.g. gas
station equipment, and the vehicle’s control sys-
tem can occur. Usually the readings issued by
the control system are more precise.
iWhen the vehicle has been parked for longer
than 20 minutes, the message
Tire pressure
is only displayed after driving for a
few minutes.
appears in the multifunction dis-
play.
Warning!G
It is the driver’s responsibility to calibrate
the TPMS on the recommended cold infla-
tion pressure. Underinflated tires affect the
ability to steer or brake the vehicle. You
might lose control over the vehicle.
iWith a spare wheel without wheel sensor
mounted, the system may still indicate the tire
inflation pressure of the removed wheel for some
minutes. If this happens, keep in mind that the
indicated value where the spare wheel is mount-
ed does not reflect the actual spare tire inflation
pressure.
Warning!G
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to
the Tire and Loading Information placard on
the driver’s door B-pillar or, if available, the
supplemental tire inflation pressure infor-
mation on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by care-
fully applying the brakes and avoiding
abrupt steering maneuvers.
Warning!G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
Tire and Loading Information placard on the
driver’s door B-pillar or, if available, the tire
inflation pressure label on the fuel filler flap.
(If your vehicle has tires of a different size
than the size indicated on the Tire and Load-
ing Information placard or, if available, the
tire inflation pressure label, you should de-
termine the proper tire inflation pressure for
those tires).
363 Practical hints
What to do if …
Display messagePossible cause/consequencePossible solution
DISTRONICCurrently Unavailable
See Operator’s ManualDistronic* is deactivated because the
functionality is impaired by external in-
terferences, e.g. high-frequency sources
such as too stations, speed measuring
systems etc.Leave the area of the external interference.
Activate Distronic* again (page 222) when
the message
DISTRONIC available again ap-
pears.
Distronic* is deactivated because the
Distronic* sensor has not sensed any
other vehicles or objects, e.g. road sign
or such, for a long time.Activate Distronic* again (page 222) when
the message
DISTRONIC available again ap-
pears.
ESPInoperative
See Operator’s Man.The ESP® as well as BAS and PRE-SAFE®
have detected a malfunction and
switched off.
The ABS may not be operational.
The brake system is still functioning nor-
mally but without the ABS, BAS, ESP
®
and PRE-SAFE® available.
Continue driving with added caution.
Have the system checked at an authorized
Mercedes-Benz Center as soon as possible.
Failure to follow these instructions increases the
risk of an accident.
Warning!G
Distronic cannot take weather conditions
into account. Switch off Distronic* or do not
turn it on if the sensor is dirty or visibility is
diminished as a result of snow, rain or fog.
The distance control may be impaired even
before the system is able to detect a dirty
sensor. The messageDISTRONIC
Currently Unavailable
See Operator’s Manual
will be displayed in the multifunction display
and Distronic* will be turned off.
370 Practical hints
What to do if …
Display messagePossible cause/consequencePossible solution
Tire pressure
is only displayed
after driving for
a few minutes
Vehicles with Advanced TPMS*:
The tire inflation pressure is being
checked.Drive the vehicle for a few minutes.
Tire Pressure
Monitor
Currently UnavailableThe TPMS or Advanced TPMS* is un-
able to monitor the tire pressure due
to a nearby radio interference
source.As soon as the causes for the malfunction are
no longer present, the Advanced TPMS* auto-
matically becomes active again after a few
minutes driving.
Tire Pressure
Monitor
InoperativeThe TPMS or Advanced TPMS* is
malfunctioning.Have the TPMS or Advanced TPMS* checked
by an authorized Mercedes-Benz Center.
Have the wheel sensors installed by an
authorized Mercedes-Benz Center.
Warning!G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle.
You may lose control of the vehicle. Contin-
ued driving with a flat tire will cause exces-
sive heat build-up and possibly a fire.