
Display messages
Possible causes/consequences and
M
MSolutions !
Parking brake inop‐ Parking brake inop‐
erative erative The yellow
!warning lamp lights up. The red !indicator lamp
flashes for about ten seconds after the electric parking brake has been applied or released. It then goes out or remains lit.
The electric parking brake is malfunctioning, e.g. because of over-
voltage or undervoltage.
X Rectify the cause of the overvoltage or undervoltage, e.g. by charg-
ing the battery or restarting the engine.
X Apply or release the electric parking brake.
If the electric parking brake still cannot be applied or released: X Switch off the ignition and turn it back on.
X Apply or release the electric parking brake.
If the electric parking brake still cannot be released: X Consult a qualified specialist workshop.
If it is still not possible to apply the electric parking brake:
X Consult a qualified specialist workshop. The yellow
!warning lamp lights up and the red !indicator
lamp flashes.
It is not possible to apply the electric parking brake manually.
X Shift the transmission to position P.
X Consult a qualified specialist workshop. J
Check brake fluid Check brake fluid
level level There is insufficient brake fluid in the brake fluid reservoir. In addition,
the J warning lamp in the instrument cluster lights up and a warn-
ing tone sounds.
G WARNING
Braking efficiency 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 Safeguard the vehicle against rolling away (Y page 167).
X Consult a qualified specialist workshop.
X Do not top up the brake fluid. This does not correct the fault. #
Check Check
brake
brakepad
padwear
wear The brake pads/linings have reached their wear limit.
X Consult a qualified specialist workshop. G
Inoperative
Inoperative One or more main features of the Mercedes-Benz Contact system are
malfunctioning.
X Consult a qualified specialist workshop. Display
messages
259On-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 Front-passenger
Front-passenger
airbag airbag
disabled
disabled See
See
Owner's Manual
Owner's Manual The front-passenger front airbag is disabled during the journey
although:
R an adult
or
R a person of the corresponding stature is on the front-passenger seat
If additional forces are applied to the seat, the weight the system
detects may be too low.
G WARNING
The front-passenger front airbag does not deploy during an accident.
This poses an increased risk of injury.
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 the ignition off.
X Have the occupant on the front-passenger seat step out of the
vehicle.
X Make sure that the seat is unoccupied, close the front-passenger
door and switch on the ignition.
X Observe the PASSENGER AIR BAG indicator lamps in the centre
console and the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R a self-diagnosis is carried out. The PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps light up simultaneously
for approximately six seconds
R the PASSENGER AIR BAG OFF indicator lamp must then light up
and remain lit after the self-diagnosis. If the indicator lamp is on,
the automatic front-passenger front airbag deactivation system
has disabled the front-passenger front airbag (Y page 45)
R the Front-passenger
Front-passenger airbag airbagenabled
enabled See
SeeOwner's
Owner's Manual
Manual
or Front-passenger
Front-passenger airbag
airbagdisabled
disabled See
SeeOwner's
Owner's Manual
Manual
display messages must not be shown in the multifunction display
X Wait for a period of at least 60 seconds until the necessary system
checks have been completed.
X Make sure that the display messages do not appear in the multi-
function display.
If these conditions are met, the front-passenger seat can be occupied again. Whether the PASSENGER AIR BAG OFF or ON indicator lamp
remains lit or goes out depends on how the automatic front-passenger
front airbag deactivation system classifies the occupant.
If the conditions are not met, the system is not operating correctly.
X Consult a qualified specialist workshop immediately.
Further information on the automatic front-passenger front airbag
deactivation feature (Y page 45).264
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Front-passenger
Front-passenger
airbag enabled See airbag enabled See
Owner's Manual Owner's Manual The front-passenger front airbag is enabled during the journey
although:
R a child, a small adult or an object weighing less than the system
weight threshold is located on the front-passenger seat
or
R the front-passenger seat is not occupied
The system may detect objects or forces that are adding to the weight
applied to the seat.
G WARNING
The airbag may deploy unintentionally.
This poses an increased risk of injury. 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 the ignition off.
X Open the front-passenger door.
X Remove the child and the child restraint system from the front-
passenger seat.
X Make sure there are no objects applying additional force to the seat.
The system may otherwise detect the additional force and interpret the seat occupant's weight as greater than it actually is.
X Make sure that the seat is unoccupied, close the front-passenger
door and switch on the ignition.
X Observe the PASSENGER AIR BAG indicator lamps in the centre
console and the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R a self-diagnosis is carried out. The PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps light up simultaneously for approximately six seconds
R the PASSENGER AIR BAG OFF indicator lamp must then light up
and remain lit after the self-diagnosis. If the indicator lamp is on, the automatic front-passenger front airbag deactivation system
has disabled the front-passenger front airbag (Y page 45)
R the Front-passenger
Front-passenger airbag airbagenabled
enabled See
SeeOwner's
Owner's Manual
Manual
or Front-passenger
Front-passenger airbag
airbagdisabled
disabled See
SeeOwner's
Owner's Manual
Manual
display messages must not be shown in the multifunction display
X Wait for a period of at least 60 seconds until the necessary system
checks have been completed.
X Make sure that the display messages do not appear in the multi-
function display.
If these conditions are met, the front-passenger seat can be occupied again. Whether the PASSENGER AIR BAG OFF or ON indicator lamp
remains lit or goes out depends on how the automatic front-passenger
front airbag deactivation system classifies the occupant.
If the conditions are not met, the system is not operating correctly.
X Consult a qualified specialist workshop immediately. Display
messages
265On-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

Engine
Display messages
Possible causes/consequences and
M
MSolutions +
Top up coolant See Top up coolant See
Owner's Manual Owner's Manual The coolant level is too low.
! Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
X Top up the coolant, observing the warning notes before doing so
(Y page 321).
If you have to top up the coolant frequently: X Contact a qualified specialist workshop and have the engine cooling
system checked. ? The fan motor is faulty.
X If the coolant temperature is below 120 †, you can continue driving
to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in moun-
tainous terrain and stop-start traffic. ?
Coolant Stop vehi‐ Coolant Stop vehi‐
cle Switch engine cle Switch engine
off off The coolant is too hot.
A warning tone also sounds.
G WARNING
Never drive with an overheated engine. Driving when your engine is
overheated can cause some fluids which may have leaked into the
engine compartment to catch fire.
In addition, steam from an overheated engine can cause serious
burns, which can occur just by opening the bonnet.
There is a risk of injury.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 167).
X Wait until the engine has cooled down.
X Make sure that the air supply to the engine radiator is not blocked,
e.g. by frozen slush.
X Do not start the engine again until the display message goes out and
the coolant temperature is below 120 †. The engine may otherwisebe damaged.
X Pay attention to the coolant temperature display.
If the temperature increases again:
X Consult a qualified specialist workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 120 †. Display messages
269On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions 4
Add 1 litre engine Add 1 litre engine
oil when next refu‐ oil when next refu‐
elling elling Mercedes-AMG vehicles: the engine oil level is too low.
! Avoid long journeys when there is too little coolant in the cooling
system. Otherwise the engine will be damaged.
X Check the oil level when next refuelling, at the latest (Y page 320).
X If necessary, top up the engine oil (Y page 320).
If you have to top up the engine oil frequently:
X Contact a qualified specialist workshop and have the engine
checked.
Information on approved engine oils can be obtained from any quali-
fied specialist workshop or on the Internet at http://bevo.mercedes-
benz.co m. 4
Engine oil level Engine oil level
Stop Stop
vehicle
vehicle Switch
Switch
engine off
engine off Mercedes-AMG vehicles: the engine oil level is too low.
There is a risk of engine damage.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 167).
X Check the engine oil level (Y page 320).
X If necessary, top up the engine oil (Y page 320).8
Reserve fuel level Reserve fuel level The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated if the fuel level drops
into the reserve range.
X Refuel at the nearest filling station. C There is very little fuel in the fuel tank.
The auxiliary heating cannot be operated.
X Refuel at the nearest filling station without fail. ¸
Replace Replace
air
aircleaner
cleaner
element
element Vehicles with a diesel engine: the engine air filter is dirty and must be
replaced.
X Consult a qualified specialist workshop. !
Clean the fuel fil‐ Clean the fuel fil‐
ter ter Vehicles with a diesel engine: there is water in the fuel filter. The water
must be drained off.
X Consult a qualified specialist workshop. Ø
Refill AdBlue See Refill AdBlue See
Owner's Manual Owner's Manual The AdBlue
®
level has fallen below the reserve range. A warning tone
also sounds.
X Have AdBlue ®
refilled as soon as possible at a qualified specialist
workshop.
or X Add at least 3.8 lof AdBlue ®
immediately (Y page 164). Display messages
271On-board computer and displays Z