Problems with the key
Problem Possible causes/consequences and
M
MSolutions You cannot lock or
unlock the vehicle
using the key. The key battery is discharged or nearly discharged.
X
Try again to lock/unlock the vehicle using the remote control
function of the key. Point the tip of the key at the driver's door
handle from close range and press the %/& button.
If this does not work:
X Check the key battery (Y page 79) and replace it if necessary
(Y page 79).
X Lock (Y page 84) or unlock (Y page 84) the vehicle using
the emergency key element. The key is faulty.
X
Lock (Y page 84) or unlock (Y page 84) the vehicle using
the emergency key element.
X Have the key checked at a qualified specialist workshop. You can no longer lock
or unlock the vehicle
using KEYLESS-GO. KEYLESS-GO is in standby mode because the vehicle has not been
unlocked for an extended period.
X
Pull the door handle and then turn the key to position 2in the
ignition lock. There is interference from a powerful source of radio waves.
X
Lock/unlock the vehicle using the remote control function of
the key. Point the tip of the key at the driver's door handle from
close range and press the %/& button. There is a fault with KEYLESS-GO.
X
Lock/unlock the vehicle using the remote control function of
the key. Point the tip of the key at the driver's door handle from
close range and press the %/& button.
X Have KEYLESS-GO checked at a qualified specialist workshop.
If this does not work:
X Check the key battery (Y page 79) and replace it if necessary
(Y page 79).
X Lock (Y page 84) or unlock (Y page 84) the vehicle using
the emergency key element. You have lost a key. X
Have the key deactivated at a qualified specialist workshop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. Key
81Opening and closing Z
Problem Possible causes/consequences and
M
MSolutions You have lost the emer-
gency key element. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. The engine cannot be
started using the key. The on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 337).
or
X Jump-start the vehicle (Y page 341).
or
X Consult a qualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The key is in the
vehicle. A door is open. Therefore, the key cannot be detected as easily.
X
Close the door and try to start the vehicle again. There is interference from a powerful source of radio waves.
X
Start your vehicle with the key in the ignition lock. Doors
Important safety notes
G
WARNING
Only for the United Kingdom: if the vehicle
has been locked with the key, the double lock
function is activated as standard. It is then not
possible to open the doors from inside the
vehicle.
Therefore, do not leave any people behind in
the vehicle, particularly children, elderly peo-
ple or people in need of special assistance if
the vehicle has been locked with the key. As
a result, they may not be able to free them-
selves in the event of an emergency. As a
result, they could be seriously or even fatally
injured by prolonged exposure to extremely
high or low temperatures, for example. In this
case, rescuing people from outside the vehi-
cle is difficult.
Deactivate the interior motion sensor before
you lock the vehicle with the key. The doors can then be opened from the inside after the
vehicle has been locked from the outside with
the key.
G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open a door from inside the vehicle at any
time, even if it has been locked
R start the vehicle using a key which has been
left in the vehicle
R release the parking brake
They could thereby endanger themselves and
others. Never leave children unsupervised in
the vehicle. Always take the key with you
when leaving the vehicle, even if you are only
leaving it for a short time. 82
DoorsOpening and closing
The colours of the indicator lamps on the but-
ton have the following meanings:
Blue Auxiliary ventilation switched on
Red Auxiliary heating switched on
Yellow Departure time preselected (Ypage 242)
Switching on the auxiliary heating/venti-
lation
X Press button :.
The red or blue indicator lamp in but-
ton :lights up.
Switching off the auxiliary heating/venti-
lation
X Press button :.
The red or blue indicator lamp in but-
ton :goes out.
Switching the auxiliary heating/venti-
lation on/off using the remote control Your vehicle comes with one remote control.
You may use two additional remote controls
for your vehicle. For more information, please
contact a qualified specialist workshop.
The remote control has a maximum range of
approximately 300 metres. This range is
reduced by:
R
sources of radio interference
R solid objects between the remote control
and the vehicle
R the remote control being in an unfavoura-
ble position in relation to the vehicle
R transmitting from an enclosed space
i The optimum range can be achieved if you
hold the remote control vertically, pointing
upwards when you press one of the but-
tons.
i A battery symbol appears in the display
when the battery in the remote control is
low. Replace the remote control battery
(Y page 140). Auxiliary heating remote control
:
Display
; . To check the status/set the depar-
ture time
= ^ To switch off the auxiliary heating/
ventilation
? u To switch on the auxiliary heating/
ventilation
A , To check the status/set the depar-
ture time
Switching on the auxiliary heating/venti-
lation
X Press the ubutton.
ON
ON is shown in the remote control display.
Switching off the auxiliary heating/venti-
lation
X Press the ^button.
OFF OFF is shown in the remote control display.
Checking the status of the auxiliary heat-
ing/ventilation
X Press the ,or. button.
The following messages may appear in the
display: Display Meaning
The auxiliary heating/
ventilation is switched
off.138
Operating the climate control systemClimate control
Always pay attention to traffic conditions
even when DISTRONIC PLUS is activated.
Otherwise, you may fail to recognise dangers
in time, cause an accident and injure yourself
and others.
The radar sensor system is switched off auto-
matically in the vicinity of radio telescope
facilities (Y page 375).
If you want DISTRONIC PLUS to assist you,
the radar sensor system must be activated
(Y page 242) and operational.
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control in the speed range between
30 km/h and 200 km/h. If a vehicle is driving
in front of you, DISTRONIC operates in the
speed range between 0 km/h and
200 km/h.
Do not use DISTRONIC PLUS on roads with
steep gradients. G
WARNING
DISTRONIC PLUS brakes your vehicle up to a
maximum of 4 m/s 2
depending on its speed.
This corresponds to approximately 40% of
your vehicle's maximum braking power. You
must also apply the brakes yourself if this
braking power is not sufficient.
If DISTRONIC PLUS detects a risk of collision
with a vehicle in front, an intermittent warning
tone sounds. In addition, the ·distance
warning lamp in the instrument cluster lights
up. Brake to avoid a collision.
Cruise control lever With the cruise control lever, you can operate
DISTRONIC PLUS and variable SPEED-
TRONIC.
The LIM indicator lamp on the cruise control
lever indicates which system you have selec-
ted:
R
LIM indicator lamp off: DISTRONIC PLUS
is selected.
R LIM indicator lamp on: variable SPEED-
TRONIC is selected. :
To store the current speed or a higher
speed
; To set the specified minimum distance
= LIM indicator lamp
? To store the current speed and call up the
last stored speed
A To store the current speed or a lower
speed
B To switch between DISTRONIC PLUS and
variable SPEEDTRONIC
C To deactivate DISTRONIC PLUS
Selecting DISTRONIC PLUS X
Check whether LIM indicator lamp =is off.
If it is off, DISTRONIC PLUS is already selec-
ted.
If it is not, press the cruise control lever in
the direction of arrow B.
LIM indicator lamp =in the cruise control
lever goes out. DISTRONIC PLUS is selec-
ted.
Activating DISTRONIC PLUS, storing
and maintaining the current speed Important safety notes
G
WARNING
The vehicle can be braked when DISTRONIC
PLUS is activated. For this reason, deactivate
DISTRONIC PLUS if the vehicle is to be set in
motion by other means (e.g. in a car wash or
by towing). Driving systems
179Driving and parking Z
or
X
Briefly press the cruise control lever in the
direction of arrow =.
Variable SPEEDTRONIC is selected. LIM
indicator lamp ;in the cruise control lever
lights up.
When you deactivate DISTRONIC PLUS, you
will see the DISTRONIC PLUS off DISTRONIC PLUS off message
in the multifunction display for approximately
five seconds.
i The last speed stored remains stored until
you switch off the engine.
DISTRONIC PLUS is automatically deactiva-
ted if:
R you engage the parking brake.
R you are driving slower than 25 km/h and
there is no vehicle in front, or if the vehicle
in front is no longer detected.
R ESP ®
intervenes or you deactivate ESP ®
.
R the transmission is in the P,Ror Nposition.
R the vehicle is near a radio telescope facility
(Y page 375).
R you switch off the radar sensor system
(Y page 242).
R you pull the cruise control lever towards
you in order to pull away, and the front-
passenger door or one of the rear doors is
open.
R the vehicle has skidded.
If DISTRONIC PLUS is deactivated, you will
hear a warning tone. You will see the DIS‐
DIS‐
TRONIC TRONIC PLUS
PLUSoff
offmessage in the multifunc-
tion display for approximately five seconds.
If the vehicle has been stopped by DISTRONIC
PLUS and a fault occurs in the system, the
Brake Brake immediately
immediately message appears in the
multifunction display. Depress the brake
pedal immediately so that the vehicle does
not roll away. DISTRONIC PLUS is then deac-
tivated, and the message disappears. Tips for driving with DISTRONIC PLUS General notes
The following contains descriptions of certain
road and traffic conditions in which you must
be particularly attentive. In such situations,
brake if necessary. DISTRONIC PLUS is then
deactivated.
Cornering, going into and coming out of a
bend
The ability of DISTRONIC PLUS to detect vehi-
cles when cornering is limited. Your vehicle
may brake unexpectedly or late.
Vehicles which are not driving in the mid-
dle of their lane
DISTRONIC PLUS may not detect vehicles
which are not driving in the middle of their
lane. The distance to the vehicle in front will
be too short. Driving systems
185Driving and parking Z
Problems with PARKTRONIC
Problem Possible causes/consequences and
M
MSolutions Only the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is deacti-
vated after approx-
imately five seconds,
and the indicator lamp
in the PARKTRONIC
button lights up. PARKTRONIC has malfunctioned and has switched off.
X
If problems persist, have PARKTRONIC checked at a qualified
specialist workshop. Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is deacti-
vated after approx-
imately five seconds. The PARKTRONIC sensors are dirty or there is interference.
X
Clean the PARKTRONIC sensors (Y page 321).
X Switch the ignition back on. The problem may be caused by an external source of radio or
ultrasound waves.
X
See if PARKTRONIC functions in a different location. Active Parking Assist
Important safety notes Active Parking Assist is an electronic parking
aid with ultrasound. Ultrasound is used to
measure the road on both sides of the vehicle.
A suitable parking space is indicated by the
parking symbol. Active steering intervention
can assist you during parking. You may also
use PARKTRONIC (Y page 188). When PARK-
TRONIC is switched off, Active Parking Assist
is also unavailable. G
WARNING
Active Parking Assist is merely an aid and may
sometimes recommend parking spaces that
are not suitable for parking. For example,
these might be spaces where parking is pro-
hibited, driveways, unsuitable surfaces, etc.
Active Parking Assist measures the parking
space as you drive past it. Any later changes to the parking space are not taken into
account. For instance, this may be the case
when the vehicle parked in front of or behind
the space changes its position or when an
obstacle is moved into the parking space.
Active Parking Assist does not relieve you of
the responsibility of paying attention. If you
rely solely on Active Parking Assist, you could
cause an accident and injure yourself and oth-
ers.
You are always responsible for safety and
must continue to pay attention to your imme-
diate surroundings when parking and
manoeuvring. G
WARNING
Objects located above the height range of
Active Parking Assist will not be detected
when the parking space is measured. These
are not taken into account when the parking 192
Driving systemsDriving and parking
vehicles, such as motorcycles or bicycles, or
only detect them too late.
Monitoring may be affected by dirty sensors,
strong spray or poor visibility caused by snow,
rain or mist, for example. In this case, vehicles
are detected late or not at all.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognise dangers in time, cause an accident
and injure yourself and others.
For Blind Spot Assist to assist you when driv-
ing, the radar sensor system must be activa-
ted (Y page 242) and operational.
The radar sensor system is switched off auto-
matically in the vicinity of radio telescope
facilities (Y page 375).
Monitoring range of the sensors
The Blind Spot Assist monitors the area up to
3.0 m behind your vehicle and directly next to
your vehicle, as shown in the diagram. Example: Saloon
G
WARNING
Blind Spot Assist monitors certain areas in the
immediate vicinity of your vehicle. Vehicles
that approach and drive past at high speeds
are not detected. There is no display and no
warning. If the lanes are very wide, it may not be pos-
sible to monitor the complete width of the
neighbouring lane. For this reason, vehicles in
the next lane may not be detected, especially
if they are driving in a staggered formation in
different lanes. This may be the case if vehi-
cles are driving at the edge of their lane that
is furthest away from your vehicle.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognise dangers in time, cause an accident
and injure yourself and others.
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
driving in the middle of their lane. This may
be the case if there are vehicles at the edge
of their lane nearest your vehicle.
Due to the nature of the system:
R warnings may be issued in error when driv-
ing close to crash barriers or similar solid
lane borders.
R warnings may be interrupted when driving
alongside long vehicles, for example lor-
ries, for a prolonged time.
The two radar sensors for Blind Spot Assist
are integrated into the sides of the rear
bumper. Make sure that the bumper is free of
dirt, ice or slush in the vicinity of the sensors.
The sensors must not be covered, for exam-
ple by cycle racks or overhanging loads. Fol-
lowing a severe impact or in the event of dam-
age to the bumpers, have the function of the
sensors checked at a qualified specialist
workshop. Blind Spot Assist may otherwise
not work properly. 204
Driving systemsDriving and parking
detected, corrective braking may help you
avoid a collision. To support the course-cor-
recting brake application, Active Blind Spot
Assist also uses the forward-facing radar sen-
sor system. Active Blind Spot Assist supports
you from a speed of approximately 30 km/ h.
The radar sensor system is switched off auto-
matically in the vicinity of radio telescope
facilities (Y page 375).
For Active Blind Spot Assist to assist you
when driving, the radar sensor system must
be activated (Y page 242) and operational.
Monitoring range of the sensors G
WARNING
Active Blind Spot Assist monitors certain
areas in the immediate vicinity of your vehicle.
Vehicles that approach and drive past at high
speeds are not detected. No visual nor audi-
ble warnings are emitted and the system does
not brake the vehicle to correct your course.
If the lanes are very wide, it may not be pos-
sible to monitor the complete width of the
neighbouring lane. For this reason, vehicles in
the next lane may not be detected, especially
if they are driving in a staggered formation.
This may be the case if vehicles are driving at
the edge of their lane that is furthest away
from your vehicle.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognise dangers in time, cause an accident
and injure yourself and others.
Active Blind Spot Assist monitors the area up
to three metres behind your vehicle and
directly next to your vehicle as shown in the
diagram. For this purpose, Active Blind Spot
Assist uses radar sensors in the rear bumper. Example: Saloon
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
driving in the middle of their lane. This may
be the case if there are vehicles at the edge
of their lane nearest your vehicle.
Due to the nature of the system:
R warnings may be issued in error when driv-
ing close to crash barriers or similar solid
lane borders.
R warnings may be interrupted when driving
alongside long vehicles, for example lor-
ries, for a prolonged time.
Two Active Blind Spot Assist radar sensors
are integrated into the front and rear bumpers
respectively. An additional radar sensor is
located behind the cover in the radiator grille.
Make sure that the sensors and the areas
around them are free of dirt, ice or slush. The
rear sensors must not be covered, e.g. by
bicycle racks or overhanging loads. Following
a severe impact or in the event of damage to
the bumpers, have the function of the sensors
checked at a qualified specialist workshop.
Blind Spot Assist may otherwise not work
properly. 208
Driving systemsDriving and parking