
As a result, Active Blind Spot Assist may nei-
ther give warnings nor intervene in such sit-
uations. There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and maintain a safe distance at the sideof the vehicle.
Radar sensors The Active Blind Spot Assist radar sensors are
integrated into the front and rear bumpers and
behind a cover in the radiator trim. Make sure
that the bumpers and the cover in the radiator
trim are free of dirt, ice or slush. The sensors
must not be covered, for example by cycle racks or overhanging loads. Following an accident or
in the event of damage to the bumpers, have the
function of the radar sensors checked at a quali-
fied specialist workshop. Active Blind Spot
Assist may otherwise no longer function prop-
erly.
Monitoring range G
WARNING
Active Blind Spot Assist does not detect all
traffic situations and road users. There is a
risk of an accident.
Always make sure that there is sufficient dis-
tance to the side for other traffic or obstacles. Active Blind Spot Assist monitors the area up to
3.0 m behi nd your vehicle and directly next to
your vehicle, as shown in the diagram. In particular, the detection of obstacles can be
impaired in the case of:
R dirt on the sensors or obscured sensors
R poor visibility, e.g. due to rain, snow or spray
Vehicles in the monitoring range are then not
reliably indicated.
Active Blind Spot Assist may not detect narrow
vehicles, such as motorcycles or bicycles, or
may only detect them too late.
If the lanes are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may be indicated, especially if the vehicles are not driv-
ing in the middle of their lane. This may be the
case if there are vehicles at the edge of their
lane.
Due to the nature of the system:
R warnings may be issued in error when driving
close to crash barriers or similar solid lane
borders
R warnings may be interrupted when driving
alongside particularly long vehicles, for exam-
ple lorries, for a prolonged time
Indicator and warning display :
Yellow indicator lamp/red warning lamp 222
Driving systemsDriving an
d parking 

Towing a trailer
If you couple up a trailer, make sure that you
have correctly established the electrical con-
nection. This can be accomplished by checking
the trailer lighting. Active Blind Spot Assist is
then deactivated. The indicator lamps in the
exterior mirrors light up yellow and the Active
Active
Blind Spot Assist not available when Blind Spot Assist not available when
towing a trailer See Owner's Manual towing a trailer See Owner's Manual
message appears in the multifunction display.
Active Lane Keeping Assist General notes
Active Lane Keeping Assist monitors the area in
front of your vehicle by means of multifunction
camera :at the top of the windscreen. Various
different areas to the front, rear and side of your 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 within a speed range
between 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 an
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 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
to the vehicle
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 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 windscreen is dirty, misted up, damaged
or covered, for instance by a sticker, in the
vicinity of the camera
R no or several, unclear lane markings are pres-
ent for one lane, e.g. in a construction area
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 small
and the lane markings thus 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 through the steering
wheel A warning may be given if a front wheel passes
over a lane marking. It will warn you by means of 224
Driving systemsDriving an
d parking 

Useful information
i This Owner's Manual describes all models,
series and optional equipment for your vehi-
cle that were available at the time of going to
press. National variations are possible. Note
that your vehicle may not be equipped with all
of the functions described. This is also the
case for systems and functions relevant to
safety.
i Read the information on qualified specialist
workshops: (Y page 25). Important safety notes
G
WARNING
Operating the integrated information systems and communications equipment in the vehicle
while driving will distract you from traffic con-
ditions. You could then lose control of the
vehicle. There is a risk of an accident.
Only operate these devices if road traffic con-
ditions permit. If you are unsure about the
surrounding conditions, pull over to a safe
location and make entries only while the vehi-
cle 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 recognise function
restrictions relevant to safety. The operating
safety of your vehicle may be impaired. There is a risk of an accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop immedi-
ately.
If the operating safety of your vehicle is
impaired, park the vehicle safely as soon as pos- sible. Contact 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 cluster illus-
tration (Y page 29). 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 29).
X Turn the brightness control knob clockwise or
anti-clockwise.
If you turn the light switch to Ã,Tor
L, 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 speedometer is divided into segments only
on vehicles with DISTRONIC PLUS.
The segments in the speedometer indicate
which speed range is available.
R Variable SPEEDTRONIC activated
(Y page 180):
The segments light up from the start of the
scale to the selected limit speed.
R DISTRONIC PLUS activated (Y page 182):
One or two segments in the set speed range
light up.
R DISTRONIC PLUS 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. Rev counter
! Do not drive in the overrevving range. Doing
so will damage the engine.
The red band in the rev counter indicates the
engine's overrevving range. Displays and operation
235On-board computer and displays Z 

Display messages
Possible causes/consequences and
M
MSolutions Collision Preven‐
Collision Preven‐
tion Assist Plus tion Assist Plus
currently unavaila‐ currently unavaila‐
ble ble
See
SeeOwner's
Owner's Man‐
Man‐
ual
ual COLLISION PREVENTION ASSIST PLUS is temporarily inoperative.
Possible causes:
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.
Once the causes listed above no longer apply, the display message
goes out.
COLLISION PREVENTION ASSIST PLUS is operational 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 Safeguard the vehicle against rolling away (Y page 167).
X Restart the engine. Collision Preven‐ Collision Preven‐
tion Assist Plus tion Assist Plus
inoperative inoperative COLLISION PREVENTION ASSIST PLUS is temporarily inoperative due
to a malfunction. Adaptive Brake Assist may also have failed.
X Consult a qualified specialist workshop immediately. PRE-SAFE inopera‐
PRE-SAFE inopera‐
tive see Owner's tive see Owner's
Manual Manual
Important functions of PRE-SAFE
®
have failed. All other occupant
safety systems, e.g. airbags, remain available.
X Consult a qualified specialist workshop immediately. PRE-SAFE Functions
PRE-SAFE Functions
currently limited currently limited
See Owner's Manual See Owner's Manual
PRE
‑SAFE ®
PLUS or PRE‑ SAFE®
Brake is temporarily inoperative.
Possible causes:
R the function is impaired due to heavy rain or snow
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 Mercedes-AMG vehicles: ESP ®
is deactivated
R the system is outside the operating temperature range
R The on-board voltage is too low.
Once the causes listed above no longer apply, the display message
goes out.
PRE ‑SAFE ®
PLUS and PRE ‑SAFE®
Brake are operational 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 Safeguard the vehicle against rolling away (Y page 167).
X Restart the engine.
X Mercedes-AMG vehicles: reactivate ESP ®
(Y page 70). 260
Display
messagesOn-board computer and displays 

Display messages
Possible causes/consequences and
M
MSolutions PRE-SAFE Functions
PRE-SAFE Functions
limited limited
See
SeeOwner's
Owner's
Manual
Manual PRE
‑SAFE ®
PLUS or PRE‑ SAFE®
Brake is unavailable due to a mal-
function. BAS PLUS with Cross-Traffic Assist may also have failed.
X Consult a qualified specialist workshop immediately. Radar
Radar
sensors
sensors dirty
dirty
See Owner's Manual
See Owner's Manual At least one of the following driving systems or driving safety systems
is temporarily restricted or inoperative:
R PRE-SAFE ®
PLUS
R PRE-SAFE ®
Brake
R COLLISION PREVENTION ASSIST PLUS
R DISTRONIC PLUS with Steering Assist and Stop&Go Pilot
R Active Lane Keeping Assist
R Active Blind Spot Assist
If the radar sensor system in front is dirty, Active Blind Spot Assist will not perform a course-correcting brake application.
Possible causes:
R the sensors in the radiator trim and/or in the bumpers are dirty
R the function of the driving system and/or driving safety system is
impaired due to heavy rain or snow
A warning tone also sounds.
Once the causes listed above no longer apply, the display message
goes out. All driving systems and driving safety systems are opera-
tional 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 Safeguard the vehicle against rolling away (Y page 167).
X Switch off the engine.
X Clean the sensors (Y page 327) in the following locations:
R in the radiator trim
R in the front bumper
R in the rear bumper, particularly in the middle of the rear bumper
X Restart the engine.
The display message disappears. ü Mercedes-AMG vehicles only:
If this symbol appears in the multifunction display, a seat belt tongue
has been inserted into a rear seat belt buckle.
Further information on the status indicator for the rear seat belts
(Y page 42). Display
messages
261On-board computer and displays Z 

Display messages
Possible causes/consequences and
M
MSolutions Vehicles with trailer tow hitch: a fuse may have blown.
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 167).
X Check the fuses (Y page 346).
X If necessary, replace the blown fuse. Observe the warning notes as
you do so.
If the multifunction display still shows the display message:
X Consult a qualified specialist workshop. b
Malfunction Malfunction
See
SeeOwn‐
Own‐
er's Manual
er's Manual The exterior lighting is faulty.
X Consult a qualified specialist workshop. b
AUTO lights inoper‐ AUTO lights inoper‐
ative ative The light sensor is faulty.
X
Consult a qualified specialist workshop. b
Switch off lights Switch off lights You leave the vehicle and the lights are switched on. A warning tone
also sounds.
X Turn the light switch to the Ãposition. b
Switch on headlamps Switch on headlamps You are driving without dipped-beam headlamps.
X
Turn the light switch to the Lorà position. Adaptive Highbeam Adaptive Highbeam
Assist Plus cur‐ Assist Plus cur‐
rently unavailable rently unavailable
See Owner's Manual See Owner's Manual Adaptive Highbeam Assist Plus is deactivated and temporarily inop-
erative.
Possible causes:
R the windscreen is dirty in the camera's field of vision
R visibility is impaired due to heavy rain, snow or fog
X Clean the windscreen.
If the system detects that the camera is fully operational again, the Adaptive Highbeam Assist Plus available again Adaptive Highbeam Assist Plus available again message is
displayed.
Adaptive Highbeam Assist Plus is operational again. Adaptive Highbeam Adaptive Highbeam
Assist Plus inoper‐ Assist Plus inoper‐
ative ative Adaptive Highbeam Assist Plus is faulty.
X Consult a qualified specialist workshop. 268
Display
messagesOn-board computer and displays 

Display messages
Possible causes/consequences and
M
MSolutions Blind Spot Assist
Blind Spot Assist
currently unavaila‐ currently unavaila‐
ble ble
See
SeeOwner's
Owner's Man‐
Man‐
ual
ual orActive BlindActive Blind
Spot Assist cur‐
Spot Assist cur‐
rently unavailable rently unavailable
See Owner's Manual See Owner's Manual Blind Spot Assist or Active Blind Spot Assist is temporarily inoperative.
Possible causes:
R the radar sensor system is outside the operating temperature range
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
The yellow 9indicator lamps also light up in the exterior mirrors.
Once the causes listed above no longer apply, the display message
goes out.
Blind Spot Assist or Active Blind Spot Assist is operational 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 Safeguard the vehicle against rolling away (Y page 167).
X Restart the engine. Blind Spot Assist Blind Spot Assist
not available when not available when
towing a trailer towing a trailer
See Owner's Man‐ See Owner's Man‐
ual ual
orActive BlindActive Blind
Spot Assist not
Spot Assist not
available when tow‐ available when tow‐
ing a trailer See ing a trailer See
Owner's Manual Owner's Manual Blind Spot Assist or Active Blind Spot Assist is deactivated while tow-
ing a trailer.
You have established the electrical connection between the trailer and
your vehicle.
X Press aon the steering wheel to confirm the display message. Blind Spot Assist Blind Spot Assist
inoperative inoperativeorActive
Active
Blind Spot Assist
Blind Spot Assist
inoperative inoperative Blind Spot Assist or Active Blind Spot Assist is faulty.
The yellow 9indicator lamps also light up in the exterior mirrors.
X Consult a qualified specialist workshop. Park Assist cancel‐
Park Assist cancel‐
led led The driver's door is open.
X Repeat the parking gap measurement and parking process with the
driver's door closed. You inadvertently touched the multifunction steering wheel while
steering intervention was active.
X While steering intervention is active, make sure not to touch the
multifunction steering wheel. The vehicle has started to skid and ESP
®
has intervened.
X Use Active Parking Assist again later (Y page 202).Park Assist inoper‐ Park Assist inoper‐
ative ative PARKTRONIC is malfunctioning or faulty.
X Follow the instructions and helpful hints in the "Problems with
PARKTRONIC" section (Y page 202).
If the multifunction display still shows the display message: X Consult a qualified specialist workshop. Display
messages
275On-board computer and displays Z 

Display messages
Possible causes/consequences and
M
MSolutions Active Parking Assist is unavailable or faulty.
X Switch off the ignition and restart the engine.
If Active Parking Assist continues to be unavailable (the jsymbol
does not appear in the multifunction display):
X Consult a qualified specialist workshop. Park Assist
Park Assist
switched off switched off The vehicle is parked. A warning tone also sounds.
The display message disappears automatically. DISTRONIC PLUS off
DISTRONIC PLUS off DISTRONIC PLUS has been deactivated.
If a warning tone also sounds, DISTRONIC PLUS has switched itself off.
(Y page 182) DISTRONIC PLUS DISTRONIC PLUS
available again available again DISTRONIC PLUS is operational again after having been temporarily
unavailable. You can now reactivate DISTRONIC PLUS (Y
page 182).DISTRONIC PLUS cur‐ DISTRONIC PLUS cur‐
rently unavailable rently unavailable
See Owner's Manual See Owner's Manual DISTRONIC PLUS is temporarily inoperative.
Steering Assist and Stop&Go Pilot are temporarily inoperative.
Possible causes:
R the function is impaired due to heavy rain or snow
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.
A warning tone also sounds.
Once the causes listed above no longer apply, the display message
goes out.
DISTRONIC PLUS is operational 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 Safeguard the vehicle against rolling away (Y page 167).
X Restart the engine. DISTRONIC DISTRONIC
PLUS
PLUSinop‐
inop‐
erative
erative DISTRONIC PLUS is faulty.
The following may have also failed:
R BAS PLUS with Cross-Traffic Assist
R PRE-SAFE ®
Brake
R Steering Assist and Stop&Go Pilot
A warning tone also sounds.
X Consult a qualified specialist workshop. DISTRONIC PLUS sus‐ DISTRONIC PLUS sus‐
pended pended You have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.
X Remove your foot from the accelerator pedal. 276
Display
messagesOn-board computer and displays