On long journeys, take regular breaks in good
time to allow yourself to rest. If you do not take a break, you will be warned again after
15 minutes at the earliest. This will only happen
if ATTENTION ASSIST still detects typical indi-
cators of fatigue or increasing lapses in concen- tration.
Vehicles with COMAND: if a warning is issued
in the multifunction display, a service station
search is performed in COMAND. You can select a service station and navigation to this service
station will then begin. This function can be acti-
vated and deactivated in COMAND. Traffic Sign Assist
General notes Traffic Sign Assist displays the maximum speed
permitted to the driver in the instrument cluster.
The data stored in the navigation system and
general traffic regulations are used to determine
the current speed limit.
As Traffic Sign Assist is a map-based system,
traffic signs put up temporarily (e.g. near road-
works) are not detected.
If a traffic sign that is relevant to your vehicle is passed, the display of the speed limits is upda-
ted.
Traffic signs with a restriction indicated by an
additional sign (e.g. in wet conditions) are also
shown.
The traffic signs are only displayed with the
restrictions if:
R The regulation must be observed with the
restriction, or
R Traffic Sign Assist is unable to determine
whether the restriction applies
If Traffic Sign Assist is unable to determine a
maximum permitted speed from any of the avail- able sources, no speed limit is displayed in the
instrument cluster either. Traffic Sign Assist is not available in all coun-
tries. In this case, symbol
0043is shown in the
assistance graphic display (Y page 237).
Important safety notes Traffic Sign Assist is only an aid and is not always
able to correctly display speed limits. Traffic
signs always have priority over the Traffic Sign
Assist display.
The system may be either functionally impaired
or temporarily unavailable if the information in
the digital street map of the navigation system is incorrect or out of date.
Instrument cluster display Displaying the assistance graphic
X Call up the assistance graphics display func-
tion using the on-board computer
(Y page 237).
X Select the Traffic Sign Assist display.
Detected traffic signs are displayed in the
instrument cluster.
Speed limit with unknown restriction 0043
Maximum permitted speed
0044 Maximum permitted speed for vehicles for
which the restriction in the additional sign is
relevant
0087 Additional sign for unknown restriction
A maximum permitted speed of 80 mph
(80 km/h) and a speed limit of 60 mph
(60 km/h) with an unknown restriction apply. Driving systems
205Driving and parking Z
Lane Tracking package
General notes The Lane Tracking package consists of Blind
Spot Assist (Y page 206) and Lane Keeping
Assist (Y page 207).
Blind Spot Assist General notes
Blind Spot Assist monitors the areas on either
side of the vehicle that are not visible to the
driver with two lateral, rear-facing radar sen-
sors. A warning display in the exterior mirrors
draws your attention to vehicles detected in the monitored area. If you then switch on the cor-
responding turn signal to change lane, you will
also receive an optical and audible warning.
Blind Spot Assist supports you from a speed of
approximately 20 mph (30 km/h).
Important safety notes G
WARNING
Blind Spot Assist does not react to:
R vehicles overtaken too closely on the side,
placing them in the blind spot area
R vehicles which approach with a large speed
differential and overtake your vehicle
As a result, Blind Spot Assist may not give
warnings in such situations. There is a risk of an accident.
Always observe the traffic conditions care-
fully, and maintain a safe lateral distance.
Blind Spot Assist is only an aid. It may fail to
detect some vehicles and is no substitute for
attentive driving. Always ensure that there is
sufficient distance to the side for other road
users and obstacles.
i USA only:
This device has been approved by the FCC as a "Vehicular Radar System". The radar sensor
is intended for use in an automotive radar
system only. Removing, tampering with, or
altering the device will void any warranties,
and is not permitted by the FCC. Do not tam-
per 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.
Radar sensors The radar sensors for Blind Spot Assist are inte-
grated into the rear bumper. Make sure that the bumpers are free from dirt, ice or slush. The
sensors must not be covered, for example by
cycle racks or overhanging loads. Following a
severe impact or in the event of damage to the
bumpers, have the function of the radar sensors
checked at a qualified specialist workshop.
Blind Spot Assist may no longer work properly.
Monitoring area
In particular, the detection of obstacles can be
impaired if:
R there is dirt on the sensors or anything else
covering the sensors
R there is poor visibility, e.g. due to fog, heavy
rain, snow or spray
R there are narrow vehicles, e.g. motorcycles or
bicycles
R the road has very wide lanes
R the road has narrow lanes
R you are not driving in the middle of the lane
R there are barriers or similar lane borders
Vehicles in the monitoring range are then not
indicated. At a distance of around 1.6 ft
(0.5m)0044 from the
vehicle, Blind Spot Assist monitors the area up
to 10 ft (3 m)next to 0087and behind 0043your
vehicle, as shown in the picture. 206
Driving systemsDriving an
d parking
Lane Keeping Assist monitors the area in front of
your vehicle with camera 0043, which is mounted
at the top of the windshield. Lane Keeping Assist
detects lane markings on the road and can warn
you before you leave your lane unintentionally.
This function is available in the range between
40 mph and 120 mph (60 km/h and 200 km/h).
A warning may be given if a front wheel passes
over a lane marking. It will warn you by means of
intermittent vibration in the steering wheel for
up to 1.5 seconds.
Important safety notes G
WARNING
Lane Keeping Assist cannot always clearly
detect lane markings.
In such cases, Lane Keeping Assist can:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Lane Keeping Assist alerts you. G
WARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There is a risk of an accident.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane Keep-ing Assist.
If you fail to adapt your driving style, Lane Keep- ing Assist can neither reduce the risk of an acci-
dent nor override the laws of physics. Lane
Keeping Assist cannot take into account the
road, traffic and weather conditions. Lane Keep- ing Assist is merely an aid. You are responsible
for the distance to the vehicle in front, for vehi-
cle speed, for braking in good time and for stay-
ing in your lane.
The Lane Keeping Assist does not keep the vehi- cle in the lane. The system may be impaired or may not function
if:
R there is poor visibility, e.g. due to insufficient
illumination of the road, or due to snow, rain,fog or heavy spray
R there is glare, e.g. from oncoming traffic, the
sun or reflection from other vehicles (e.g. if
the road surface is wet)
R the windshield is dirty, fogged up, damaged or
covered, for instance by a sticker, in the vicin-
ity of the camera
R there are no or several unclear lane markings
for one lane, e.g. roadworks
R the lane markings are worn away, dark or cov-
ered up, e.g. by dirt or snow
R the distance to the vehicle in front is too short
and thus the lane markings cannot be detec-
ted
R the lane markings change quickly, e.g. lanes
branch off, cross one another or merge
R the road is narrow and winding
R there are highly variable shade conditions on
the roadway
Switching on Lane Keeping Assist X Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard
Standard orAdaptive Adaptive (Ypage 238).
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected,
the lines in the assistance graphic are shown
in green (Y page 237). Lane Keeping Assist is
ready for use.
Standard If Standard
Standard is selected, no warning vibration
occurs if:
R you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
R a driving safety system intervenes, e.g. ABS,
BAS or ESP ®
.
Adaptive
When Adaptive Adaptive is selected, no warning vibra-
tion occurs if:
R you have switched on the turn signal; in this
event, the warnings are suppressed for a cer-
tain period of time.
R a driving safety system intervenes, e.g. ABS,
BAS or ESP ®
. 208
Driving systemsDriving and parking
vehicle are also monitored with the aid of the
radar sensor system. Active Lane Keeping
Assist detects lane markings on the road and
can warn you before you leave your lane unin-
tentionally. If you do not react to the warning, a
lane-correcting application of the brakes can
bring the vehicle back into the original lane.
This function is available in a speed range
between 40 mph and 120 mph (60 km/h and
200 km/h).
For Active Lane Keeping Assist to assist you
when driving, the radar sensor system must be
operational.
Important safety notes
If you fail to adapt your driving style, Active Lane Keeping Assist can neither reduce the risk of
accident nor override the laws of physics. Active Lane Keeping Assist cannot take into account
road, weather or traffic conditions. Active Lane
Keeping Assist is only an aid. You are responsi-
ble for the distance to the vehicle in front, for
vehicle speed, for braking in good time and for
staying in your lane.
Active Lane Keeping Assist cannot continuously
keep your vehicle in its lane. G
WARNING
Active Lane Keeping Assist cannot always
clearly detect lane markings.
In such cases, Active Lane Keeping Assist
can:
R give an unnecessary warning and then
make a course-correcting brake application
R neither give a warning nor intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and keep within the lane, especially
if Active Lane Keeping Assist alerts you. Ter-
minate the intervention in a non-critical driv-
ing situation.
The system may be impaired or may not function if:
R there is poor visibility, e.g. due to insufficient
illumination of the road, or due to snow, rain,fog or heavy spray
R there is glare, e.g. from oncoming traffic, the
sun or reflection from other vehicles (e.g. if
the road surface is wet) R
the windshield is dirty, fogged up, damaged or
covered, for instance by a sticker, in the vicin- ity of the camera
R there are no or several unclear lane markings
for one lane, e.g. roadworks
R the lane markings are worn away, dark or cov-
ered up, e.g. by dirt or snow
R the distance to the vehicle in front is too short
and thus the lane markings cannot be detec-
ted
R the lane markings change quickly, e.g. lanes
branch off, cross one another or merge
R the road is narrow and winding
R there are highly variable shade conditions on
the roadway
R no vehicle is detected in the adjacent lane and
there are broken lane markings
Warning vibration in the steering wheel
A warning may be given if a front wheel passes
over a lane marking. It will warn you by means of intermittent vibration in the steering wheel for
up to 1.5 seconds.
In order that you are warned only when neces-
sary and in good time if you cross the lane mark-
ing, the system detects certain conditions and
warns you accordingly.
The warning vibration occurs earlier if:
R you approach the outer lane marking on a
bend
R the road has very wide lanes, e.g. a freeway
R the system detects solid lane markings
The warning vibration occurs later if:
R the road has narrow lanes
R you cut the corner on a bend
Lane-correcting brake application G
WARNING
A lane-correcting brake application cannot
always bring the vehicle back into the original lane. There is a risk of an accident.
Always steer, brake or accelerate yourself,
especially if Active Lane Keeping Assist warns
you or makes a lane-correcting brake appli-
cation. G
WARNING
Active Lane Keeping Assist does not detect
traffic conditions or road users. In very rare 212
Driving systemsDriving and parking
R
is affected more by strong crosswinds
R demands more sensitive steering
R has a larger turning circle
This could impair the handling characteristics.
When towing a trailer, always adjust your speed to the current road and weather conditions. Do
not exceed the maximum permissible speed for
your vehicle/trailer combination. Notes on towing a trailer
General notes !
If you have a trailer tow hitch retrofitted,
changes to the cooling system and drive train may be necessary, depending on the vehicle
type.
If you have a trailer tow hitch retrofitted,
observe the anchorage points on the chassis
frame.
R Do not exceed the legally prescribed maxi-
mum speed for vehicle/trailer combinations
in the relevant country.
This lowers the risk of an accident.
R Only install an approved trailer coupling on
your vehicle.
More information on availability and installa-
tion can be obtained at any qualified special-
ist workshop.
R The bumpers of your vehicle are not suitable
for installing detachable trailer couplings.
R Do not install hired trailer couplings or other
detachable trailer couplings on the bumpers
of your vehicle.
R If you no longer need the ball coupling,
remove it from the ball coupling recess. This
will reduce the risk of damage to the ball cou-
pling.
When towing a trailer, set the tire pressure on
the rear axle of the towing vehicle for the max-
imum load. You will find the values in the tire
pressure table in the fuel filler flap of the vehicle (Y page 369).
Please note that when towing a trailer, the fol-
lowing driving systems have limited availability
or are not available at all:
R Parking Assist PARKTRONIC (Y page 188)
R Blind Spot Assist (Y page 206)
R Active Lane Keeping Assist (Y page 211)On vehicles without level control, the height of
the ball coupling will alter according to the load
placed on the vehicle. If necessary, use a trailer
with a height-adjustable drawbar.
You will find installing dimensions and loads
under "Technical data" (Y page 394).
Driving tips Also observe the notes on pulling away with a
trailer (Y
page 138).
The maximum permissible speed for vehicle/
trailer combinations depends on the type of
trailer. Before beginning the journey, check the
trailer's documents to see what the maximum
permissible speed is for your trailer. Observe the
legally permissible maximum speed in the rele-
vant country.
For certain Mercedes-Benz vehicles, the maxi-
mum permissible rear axle load is increased
when towing a trailer. See "Technical data" to
find out whether this applies to your vehicle
(Y page 394). If you utilize any of the added
maximum rear axle load when towing a trailer,
the vehicle/trailer combination may not exceed
a maximum speed of 60 mph (100 km/h) for
reasons concerning the operating permit. This
also applies in countries in which the maximum
permissible speed for car/trailer combinations
is greater than 60 mph (100 km/h).
When towing a trailer, your vehicle's handling
characteristics will be different in comparison
with when driving without a trailer.
Use the left-hand steering wheel paddle shifter
to shift into a lower gear in good time on long
and steep downhill gradients.
This also applies if you have activated cruise
control or Active Distance Assist DISTRONIC.
This will use the braking effect of the engine, so that less braking will be required to maintain the
speed. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly. If you need additional
braking, depress the brake pedal repeatedly
rather than continuously.
Driving tips If the trailer swings from side to side:
X Do not accelerate.
X Do not counter-steer.
X Brake if necessary. Towing a trailer
221Driving and parking Z
Most U.S. states and all Canadian provinces
require by law:
R Safety chains between the towing vehicle and
the trailer. The chains should be cross-woundunder the trailer drawbar. They must be fas-
tened to the vehicle's trailer coupling, not to
the bumper or the axle.
Leave enough play in the chains to make tight
cornering possible.
R A separate brake system for certain types of
trailer.
R Safety switch for braked trailers. Check the
specific legal requirements applicable to your
state.
If the trailer becomes detached from the tow-
ing vehicle, the safety feature triggers the
trailer brakes. Towing a trailer
There are numerous legal requirements con-
cerning the towing of a trailer, e.g. speed restric-
tions. Make sure that your car/trailer combina- tion complies with the local regulations:
R in your place of residence
R in the location to which you are driving
The police and local authorities can provide reli-
able information.
Observe the following when towing a trailer:
R To gain driving experience and to become
accustomed to the new handling characteris-
tics, you should practice the following in a
traffic-free location:
- cornering
- stopping
- backing up
R Before driving, check:
- trailer tow hitch
- safety switch for braked trailers
- safety chains
- electrical connections
- lights
- wheels
R Adjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
R If the trailer has electronically controlled
brakes, pull away carefully. Brake manually using the brake controller and check whether
the brakes function correctly.
R Secure any objects on the trailer to prevent
the cargo from slipping when the vehicle is in
motion.
R When you couple up a trailer, check at regular
intervals that the load is firmly secured. If the trailer is equipped with trailer lights and
brakes, check the trailer to ensure that these
are working.
R Bear in mind that the handling will be less
stable when towing a trailer than when driving
without one. Avoid sudden steering move-
ments.
R The vehicle/trailer combination is heavier,
accelerates more slowly, has a decreased
gradient climbing capability and a longer
braking distance.
It is more susceptible to side winds and
requires more careful steering.
R If possible, do not brake suddenly, but instead
depress the brake pedal moderately at first sothat the trailer can activate its brakes. Then
increase the pressure on the brake pedal.
R If the automatic transmission repeatedly
shifts between gears on uphill or downhill gra-
dients, shift to a lower gear using the left-hand
steering wheel paddle shifter.
A lower gear and lower speed reduce the risk of engine failure.
R When driving downhill, shift to a lower gear to
utilize the engine's braking effect.
Avoid continuous brake application as this
may overheat the vehicle brakes and, if instal- led, the trailer brakes.
R If the coolant temperature increases dramat-
ically while the air-conditioning system is
switched on, switch off the air-conditioning
system.
Coolant heat can also be dissipated by open-
ing the windows and switching the ventilation blower and the interior temperature to the
highest level.
R When overtaking, pay particular attention to
the extended length of your vehicle/trailer
combination.
Due to the length of the vehicle/trailer com-
bination, you require additional road space in
relation to the vehicle you are overtaking
before you can change back to the original
lane. 224
Towing a trailerDriving and parking
Important safety notes
G
WARNING
If you operate information systems and com-
munication equipment integrated in the vehi- cle when driving, you may be distracted from
the traffic situation. You could also lose con-
trol of the vehicle. There is a risk of an acci-
dent.
Only operate this equipment when the traffic
situation permits. If you are not sure that this
is possible, park the vehicle paying attention
to traffic conditions and operate the equip-
ment when the vehicle is stationary.
You must observe the legal requirements for the country in which you are currently driving whenoperating the on-board computer. G
WARNING
If the instrument cluster has failed or mal-
functioned, you may not recognize function
restrictions in systems relevant to safety. The operating safety of your vehicle may be
impaired. There is a risk of an accident.
Pull over as soon as it is safe to do so and
consult a qualified specialist workshop.
The on-board computer only shows messages or
warnings from certain systems in the multifunc- tion display. You should therefore make sure
your vehicle is operating safely at all times.
For an overview, see the instrument panel illus-
tration (Y page 37).
Plug-in hybrid: be sure to read the separate
Operator's Manual. Otherwise, you may not rec-
ognize dangers. Displays and operation
Instrument cluster lighting
The lighting in the instrument cluster, in the dis- plays and the controls in the vehicle interior can
be adjusted using the brightness control knob.
The brightness control knob is located on the
bottom left of the instrument cluster
(Y page 37). X
Turn the brightness control knob clockwise or
counter-clockwise.
If you turn the light switch to 0058,0060or
0058, the brightness is dependent upon the
brightness of the ambient light.
i The light sensor in the instrument cluster
automatically controls the brightness of the
multifunction display.
In daylight, the displays in the instrument
cluster are not illuminated. Speedometer with segments
The segments in the speedometer indicate
which speed range is available.
R Cruise control activated (Y page 169):
The segments light up from the stored speed to the maximum speed.
R Active Distance Assist DISTRONIC activated
(Y page 171):
One or two segments in the set speed range
light up.
R Active Distance Assist DISTRONIC detects a
vehicle in front moving more slowly than the
stored speed:
The segments between the speed of the vehi- cle in front and the stored speed light up. Tachometer
! Do not drive in the overrevving range, as this
could damage the engine.
The red band in the tachometer indicates the
engine's overrevving range.
The fuel supply is interrupted to protect the
engine when the red band is reached. Outside temperature display
You should pay special attention to road condi-
tions when temperatures are around freezing
point.
Bear in mind that the outside temperature dis-
play indicates the temperature measured and
does not record the road temperature.
The outside temperature display is in the multi-
function display (Y page 231). Displays and operation
229On-board computer and displays Z
Display messages
Possible causes/consequences and
0050
0050Solutions The yellow
0024warning lamp lights up and the red 0049(USA only)
or 0024 (Canada only) indicator lamp flashes.
It is not possible to apply the electric parking brake manually.
X Shift the transmission to position 005D.
X Visit a qualified specialist workshop. 0027
(USA only)
004D (Canada only)
Check Brake Fluid
Check Brake Fluid
Level
Level There is not enough brake fluid in the brake fluid reservoir. In addition,
the 0027 (USA only) or 004D(Canada only) warning lamp lights up in
the instrument cluster and a warning tone sounds.
G WARNING
The braking effect may be impaired.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 156).
X Consult a qualified specialist workshop.
X Do not add brake fluid. This does not correct the malfunction. 0026
Check Check
Brake
Brake Pad
PadWear
Wear The brake pads/linings have reached their wear limit.
USA only: the red
0027brake system warning lamp is lit while the
engine is running.
X Visit a qualified specialist workshop. 0053
Inoperative Inoperative One or more main features of the mbrace system are malfunctioning.
X Visit a qualified specialist workshop. Active
Active
Brake
Brake Assist
Assist
Functions
Functions Currently
Currently
Limited See Opera‐
Limited See Opera‐
tor's Manual tor's Manual Active Brake Assist with cross-traffic function is temporarily inopera-
tive.
Possible causes are:
R the radar sensor system is temporarily inoperative, e.g. due to elec-
tromagnetic radiation emitted by nearby TV or radio stations or
other sources of electromagnetic radiation
R the system is outside the operating temperature range
R the on-board voltage is too low
When the causes stated above no longer apply, the display message
disappears.
Active Brake Assist with cross-traffic function or PRE ‑SAFE®
PLUS is
functional again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 156).
X Restart the engine. 250
Display
messagesOn-board computer and displays