
Display messages
Possible causes/consequences and
M
MSolutions Active Lane Keep‐
Active Lane Keep‐
ing Assist cur‐ ing Assist cur‐
rently rently
unavailable
unavailable
See Owner's Manual
See Owner's Manual Active Lane Keeping Assist 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
R there have been no lane markings for an extended period
R the lane markings are worn, dark or covered, e.g. by dirt or snow
Once the causes listed above no longer apply, the display message
goes out.
Active Lane Keeping 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 181).
X Clean the windscreen. Active Lane Keep‐ Active Lane Keep‐
ing Assist inoper‐ ing Assist inoper‐
ative ative Active Lane Keeping Assist is faulty.
X Consult a qualified specialist workshop. Active Blind Spot
Active Blind Spot
Assist currently Assist currently
unavailable See unavailable See
Owner's Manual Owner's Manual 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
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation
Once the causes listed above no longer apply, the display message goes out.
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 181).
X Restart the engine. Active Blind Spot Active Blind Spot
Assist inoperative Assist inoperative Active Blind Spot Assist is faulty.
X Consult a qualified specialist workshop. Display
messages
289On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Park
Park
Assist
Assist cancel‐
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 touched the multifunction steering wheel while steering inter-
vention 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 215).Park
Park
Assist
Assist inoper‐
inoper‐
ative
ative PARKTRONIC is malfunctioning or faulty.
X Follow the instructions and helpful hints in the "Problems with
PARKTRONIC" section (Y page 215).
If the multifunction display still shows the display message: X Consult a qualified specialist workshop. 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
is not shown 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.
Night View Assist Night View Assist
currently unavail‐ currently unavail‐
able able Night View Assist Plus is deactivated and temporarily inoperative.
Possible causes:
R the windscreen is dirty in the camera's field of vision
R the camera in the radiator trim is dirty
R visibility is impaired due to heavy rain, snow or fog
R the outside temperature is too high
X Clean the windscreen.
X Clean the camera in the radiator trim.
If the system has been switched off due to excessive outside tem- peratures, the system will switch back on automatically once it has
cooled down.
If the system detects that the camera is fully operational, the dis- play message disappears.
Night View Assist Plus is operational again. 290
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions DISTRONIC PLUS
DISTRONIC PLUS
available again available again DISTRONIC PLUS is operational again after having been tempo-
rarily unavailable. You can now reactivate DISTRONIC PLUS
(Y
page 194). DISTRONIC DISTRONIC
PLUS
PLUScur‐
cur‐
rently
rently unavailable
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 radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions 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 181).
X Restart the engine. DISTRONIC PLUS DISTRONIC PLUS
inoperative inoperative 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 DISTRONIC
PLUS
PLUSsus‐
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. DISTRONIC PLUS
DISTRONIC PLUS
- - - mph - - - mph An activation condition for DISTRONIC PLUS is not fulfilled.
X Check the activation conditions for DISTRONIC PLUS
(Y page 194). 292
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Tyre press. moni‐
Tyre press. moni‐
tor currently tor currently
unavailable unavailable No signals can be received from the tyre pressure sensors due to
strong RF interference. The tyre pressure monitor is temporarily
malfunctioning.
X Drive on.
The tyre pressure monitor restarts automatically as soon as the
cause has been rectified. Wheel sensor(s) Wheel sensor(s)
missing missing There is no signal from the tyre pressure sensor of one or several
wheels. The pressure of the affected tyre is not displayed in the
multifunction display.
X Have the faulty tyre pressure sensor replaced at a qualified spe-
cialist workshop. Tyre press. moni‐ Tyre press. moni‐
tor tor
inoperative
inoperative No
No
wheel sensors
wheel sensors The wheels fitted do not have suitable tyre pressure sensors. The
tyre pressure monitor is deactivated.
X Fit wheels with suitable tyre pressure sensors.
The tyre pressure monitor is activated automatically after driv-
ing for a few minutes. Tyre press. moni‐ Tyre press. moni‐
tor inoperative tor inoperative The tyre pressure monitor is faulty.
X Consult a qualified specialist workshop. Vehicle
Display messages
Possible causes/consequences and
M
MSolutions To start engine,
To start engine,
shift to either P shift to either P
or N or N You have attempted to start the engine with the transmission in
position
Ror D.
X Shift the selector lever to position Por N. Apply brake to Apply brake to
deselect Park (P) deselect Park (P)
position position You have attempted to shift the selector lever to position
D,Ror N
without depressing the brake pedal.
X Depress the brake pedal. To shift out of P
To shift out of P
or N, depress or N, depress
brake and start brake and start
engine engine With the engine switched off, you have attempted to shift the
selector lever out of position
Por Ninto another transmission
position.
X Depress the brake pedal.
X Start the engine. Display
messages
297On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Auxiliary battery
Auxiliary battery
malfunction malfunction The auxiliary battery for the transmission is no longer being
charged.
X Consult a qualified specialist workshop at the next opportunity.
X Until then, set the selector lever to position Pbefore you switch
off the engine.
X Before leaving the vehicle, apply the electric parking brake. N N The boot lid is open.
X Close the boot lid. M
M The bonnet is open. A warning tone also sounds.
G WARNING
The open bonnet may then block your view when the vehicle is in
motion.
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.
X Safeguard the vehicle against rolling away (Y page 181).
X Close the bonnet. Active bonnet mal‐ Active bonnet mal‐
function See Own‐ function See Own‐
er's Manual er's Manual The active bonnet (pedestrian protection) is not active due to a
malfunction or because it has already been triggered.
X Consult a qualified specialist workshop. C C At least one door is open. A warning tone also sounds.
X Close all doors. _
Front left seat Front left seat
backrest not backrest not
locked locked
orFront
Front
right seat back‐
right seat back‐
rest not locked
rest not locked The driver's or front-passenger seat backrest is not engaged. A
warning tone also sounds.
X Push the backrest back until it engages. &
inoperative Bat‐ inoperative Bat‐
tery low tery low the on-board voltage is too low The auxiliary heating (Y
page 149)
has switched itself off. The auxiliary heating cannot be switched
on.
X Drive for a considerable distance.
The battery charges. The auxiliary heating is operational again as
soon as the on-board electrical system voltage is sufficient. Display
messages
299On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions &
inoperative inoperative
Refuel
Refuel
vehicle
vehicle There is too little fuel in the fuel tank. The auxiliary heating cannot
be switched on (Y page 149).
X Refuel at the nearest filling station. &
inoperative See inoperative See
Owner's Man. Owner's Man. The auxiliary heating is temporarily malfunctioning or faulty.
X When the vehicle is on a level surface and the engine has cooled
down, make up to four attempts to switch on the auxiliary heat- ing, waiting several minutes between each attempt
(Y page 149).
X If the auxiliary heating does not switch on, consult a qualified
specialist workshop. Ð
Power Power
steering
steering mal‐
mal‐
function See Own‐
function See Own‐
er's Manual er's Manual The power steering assistance is faulty.
A warning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a risk of an accident. X Check whether you are able to apply the extra force required.
X If you are able to steer safely: carefully drive on to a qualified
specialist workshop.
X If you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop. Telephone No ser‐ Telephone No ser‐
vice vice Your vehicle is outside the network provider's transmitter/
receiver range.
X Wait until the mobile phone operational readiness symbol
appears in the multifunction display. ¥
Top Top
up
upwasher
washer fluid
fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
X Top up the washer fluid (Y page 343).300
Display
messagesOn-board computer and displays

Key
Display messages
Possible causes/consequences and
M
M Solutions Â
Key does not Key does not
belong to vehicle belong to vehicle You have put the wrong key in the ignition lock.
X Use the correct key. Â
Replace key Replace key The key needs to be replaced.
X Consult a qualified specialist workshop. Â
Change key batter‐ Change key batter‐
ies ies The key battery is discharged.
X Replace the battery (Y page 88).Â
Key not detected Key not detected
(white display mes-
sage) The key is currently undetected.
X Change the location of the key in the vehicle.
If the key still cannot be detected: X Insert the key into the ignition lock and turn it to the desired
position. Â
Key not detected Key not detected
(red display message) The key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle to prevent it from rolling away (Y page 181).
X Locate the key.
X Press aon the steering wheel to confirm the display mes-
sage. Display
messages
301On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Because there is interference from a strong source of radio waves,
the key is not detected whilst the engine is running.
A warning tone also sounds.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle to prevent it from rolling away (Y page 181).
X Insert the key into the ignition lock and bring into key mode. Â
Remove starting Remove starting
button, then button, then
insert key insert key The key is continually undetected.
The key detection function has a temporary malfunction or is
faulty. A warning tone also sounds.
X Insert the key into the ignition lock and turn it to the desired
position.
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
General notes
Some systems carry out a self-diagnosis when the ignition is switched on. Several warning and indicator lamps can thereby temporarily light up or flash. This behaviour is non-critical. These
warning and indicator lamps only indicate a malfunction if they light up or flash after the engine is started or during a journey. Safety
Seat belts Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ü
N
Only for certain countries: the red seat belt warning lamp lights up for
6 seconds after the engine starts.
The seat belt warning lamp reminds the driver and front passenger to fasten
their seat belts.
X Fasten your seat belt (Y page 46).ü
N
Only for certain countries: the red seat belt warning lamp lights up after the
engine starts. In addition, a warning tone sounds for up to 6 seconds.
The driver's seat belt is not fastened.
X Fasten your seat belt (Y page 46).
The warning tone ceases. 302
Wa
rning and indi cator lamps in the instrument clusterOn-board computer and displays