
Display messages Possible causes/consequences and
M Solutions#
Check Brake Pad
Wear The brake pads/linings have reached their wear limit.
X
Visit a qualified specialist workshop. G
mbrace Inoperative One or more main features of the mbrace system are
malfunctioning.
X
Have the mbrace system checked immediately at a qualified
specialist workshop. PRE-SAFE
Inoperative See
Operator's Manual
Important functions of PRE-SAFE
®
have failed. All other occupant
safety systems, e.g. air bags, remain available.
X Visit a qualified specialist workshop immediately. PRE-SAFE
Functions
Currently Limited
See Operator's
Manual
PRE-SAFE
®
Brake is temporarily inoperative. Possible causes are:
R function is impaired due to heavy rain or snow.
R the sensors in the radiator grill and the bumper are dirty.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
R AMG vehicles: ESP ®
is deactivated.
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.
PRE-SAFE ®
Brake 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 Secure the vehicle against rolling away ( Y page 157).
X Clean the sensors in the radiator grill and the bumper
(Y page 307).
X Restart the engine.
X AMG vehicles: reactivate ESP ®
(Y page 67). PRE-SAFE
Functions Limited
See Operator's
Manual
PRE-SAFE
®
Brake is inoperative due to a malfunction. BAS PLUS
or the distance warning signal may also have failed.
X Visit a qualified specialist workshop.232
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M SolutionsFront Passenger
Airbag Enabled
See Operator's
Manual The front-passenger air bag and front-passenger knee bag are
enabled during the journey, even though:
R
a child, a small adult or an object weighing less than the
system's weight threshold is located on the front-passenger
seat.
or
R the front-passenger seat is unoccupied.
The system may detect objects or forces applying additional
weight on the seat.
G WARNING
The front-passenger front air bag and front passenger knee bag
may be triggered unintentionally.
There is 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 Secure the vehicle against rolling away ( Y page 157).
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 that there are no objects on the seat adding to the
weight.
The system may otherwise detect the additional weight and
interpret the seat occupant's weight as greater than it actually
is.
X Keep the seat unoccupied, close the front-passenger door and
switch on the ignition.
X Observe the ^a indicator lamp in the center console and
the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 45
indicator lamp must light up and remain lit. When
the indicator lamp is on, OCS (Occupant Classification System)
has deactivated the front-passenger air bag and front-
passenger knee bag ( Y page 45).
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabled See
Operator's Manual display messages must not be shown in
the multifunction display.234
Display messages
On-board computer and displays

Display messages Possible causes/consequences and
M SolutionsX
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
multifunction display.
If these conditions are fulfilled, the front-passenger seat can be
occupied again. Whether the 45 indicator lamp remains lit
or goes out depends on how OCS classifies the occupant.
If the conditions are not fulfilled, the system is not operating
correctly.
X Visit a qualified specialist workshop immediately.
For further information about the Occupant Classification System,
see ( Y page 45). Front Passenger
Airbag Disabled
See Operator's
Manual The front-passenger air bag and front-passenger knee bag are
deactivated during the journey, although:
R
an adult
or
R a person larger than a certain size is occupying the front-
passenger seat.
If additional forces are applied to the seat, the system may
interpret the occupant's weight as lower than it actually is.
G WARNING
The front-passenger front air bag and front passenger knee bag
may not be triggered in the event of an accident.
There is 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 Secure the vehicle against rolling away ( Y page 157).
X Switch the ignition off.
X Have the occupant get out of the vehicle.
X Keep the seat unoccupied, close the front-passenger door and
switch on the ignition.
X Observe the 45
indicator lamp in the center console and
the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 45
indicator lamp must light up and remain lit. When
the indicator lamp is on, OCS has deactivated the front-
passenger air bag and front-passenger knee bag ( Y page 45).
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabled See Display messages
235
On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions?
Coolant Too Hot
Stop Vehicle Turn
Engine Off The coolant is too hot.
A warning tone also sounds.
G WARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 157).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the display message goes out
and the coolant temperature is under 248 ‡ (120
†).
Otherwise, the engine could be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to
248 ‡ (120 †).240
Display messages
On-board computer and displays

Display messages Possible causes/consequences and
M Solutions# The battery is not being charged.
A warning tone also sounds.
Possible causes are:
R
a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 157).
X Open the hood.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do
not continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is not damaged:
X Visit a qualified specialist workshop. 4
Check Engine Oil
At Next Refueling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
X
Check the oil level when next refueling, at the latest
(Y page 299).
X If necessary, add engine oil ( Y page 300).
X Have the engine checked at a qualified specialist workshop if
engine oil needs to be added more often than usual.
! Avoid long journeys with too little engine oil. The engine will
otherwise be damaged.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
www.mbusa.com (USA only). Display messages
241
On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions¨
Vehicle Rising Your vehicle is adjusting to the level you have selected.
¨
Vehicle Rising
Wait Briefly The vehicle level is too low when the vehicle is stationary. A
warning tone also sounds.
X
Do not pull away.
The vehicle level is set when the display message disappears. ¨
STOP Car Too Low You have pulled away while the vehicle level is still too low.
AIRMATIC sets the vehicle to the selected level after a short
period.
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 157).
X Wait until the display message disappears before pulling away. AIRMATIC is defective. A warning tone also sounds.
X
Do not drive faster than 50 mph (80km/h).
X Make only slight steering movements. Otherwise, the front
fender
or the tires could be damaged if the steering movement
is too large.
X Listen for scraping sounds.
X Pull over and stop the vehicle safely, paying attention to road
and traffic conditions, and select a higher vehicle level.
Depending on the malfunction, it may be possible to raise the
vehicle.
X Visit a qualified specialist workshop. ¨
Malfunction The AIRMATIC function is restricted. The vehicle's handling
characteristics may be affected.
X
Do not drive faster than 50 mph (80km/h).
X Visit a qualified specialist workshop. ë
Off The HOLD function is deactivated. the vehicle is skidding.
A warning tone also sounds.
X
Reactivate the HOLD function later (Y page 178). Radar Sensors
Deactivated See
Operator's Manual The radar sensor system is deactivated.
X
Switch on the radar sensor system (Y page 223). Display messages
243
On-board computer and displays Z

Display messages Possible causes/consequences and
M SolutionsLane Keeping
Assist Currently
Unavailable See
Operator's Manual
or Active Lane
Keeping Assist
Currently
Unavailable See
Operator's Manual Lane Keeping Assist or Active Lane Keeping Assist is deactivated
and temporarily inoperative. Possible causes are:
R
the windshield in the camera's field of vision is dirty.
R visibility is impaired due to heavy rain, snow or fog.
R there are no lane markings for a longer period.
R the
lane markings are worn, dark or covered, e.g. by dirt or snow.
When the causes stated above no longer apply, the display
message disappears.
Lane Keeping Assist or 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 Secure the vehicle against rolling away ( Y page 157).
X Clean the windshield. Lane Keeping
Assist
Inoperative or
Active Lane
Keeping Assist
Inoperative Lane Keeping Assist or Active Lane Keeping Assist is defective.
X
Visit a qualified specialist workshop.244
Display messages
On-board computer and displays

Display messages Possible causes/consequences and
M SolutionsBlind Spot Assist
Currently
Unavailable See
Operator's Manual
or Active Blind
Spot Assist
Currently
Unavailable See
Operator's Manual Blind Spot Assist or Active Blind Spot Assist is temporarily
inoperative. Possible causes are:
R
the sensors are dirty.
R function is impaired due to heavy rain or snow.
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
stations or other sources of electromagnetic radiation.
The yellow 9 indicator lamps also light up in the exterior
mirrors.
When the causes stated above no longer apply, the display
message disappears.
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 Secure the vehicle against rolling away ( Y page 157).
X Clean the sensors ( Y page 307).
X Restart the engine. Blind Spot Assist
Inoperative or
Active Blind Spot
Assist Inoperative Blind Spot Assist or Active Blind Spot Assist is defective.
The yellow
9 indicator lamps also light up in the exterior
mirrors.
X Visit a qualified specialist workshop. Park Assist
Canceled The driver's door is open and the driver's seat belt has not been
fastened.
X
Repeat the parking process with the seat belt fastened and the
driver's door closed. You have inadvertently touched the multifunction steering wheel
while steering intervention was active.
X
While steering intervention is active, make sure that the
multifunction steering wheel is not touched unintentionally. The vehicle has started to skid and ESP
®
has intervened.
X Use Active Parking Assist again later (Y page 186). Display messages
245On-board computer and displays Z