Display messages Possible causes/consequences and
M SolutionsThe yellow
! warning lamp lights up. If you manually apply or
release the electric parking brake, the red F (USA
only)/! (Canada only) indicator lamp flashes.
The electric parking brake is malfunctioning. It is not possible to
apply the electric parking brake manually.
X Shift the transmission to P.
X Visit a qualified specialist workshop.
i If you do not wish the electric parking brake to be applied,
leave the
ignition switched on, e.g. when washing the vehicle in
an automatic car wash or when having the vehicle towed.
Exception: when having the vehicle towed with the rear axle
raised ( Y page 518). F(USA
only)!(Canada
only)
Parking Brake
Inoperative The yellow
! warning lamp lights up. The red F (USA
only)/! (Canada only) 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
overvoltage or undervoltage.
X Remove the cause for the overvoltage or undervoltage, e.g. by
charging the battery or restarting the engine.
X Engage or release the electric parking brake.
If it remains impossible to apply or release the electric parking
brake:
X Switch off the ignition and turn it back on.
X Engage or release the electric parking brake.
If the electric parking brake still cannot be released:
X Consult a qualified specialist workshop. The display message is only shown while the vehicle is in motion.
The yellow
! warning lamp lights up and the red F (USA
only)/ ! (Canada only) indicator lamp flashes.
It is not possible to apply the electric parking brake manually.
X Shift the transmission to P.
X Visit a qualified specialist workshop. Display messages
229
On-board computer and displays Z
Display messages Possible causes/consequences and
M SolutionsF(USA
only)!(Canada
only)
Turn On the
Ignition to
Release the
Parking Brake The red
F
(USA only)/! (Canada only) indicator lamp lights
up.
You attempted to release the electric parking brake while the
ignition was switched off.
X SmartKey: turn the SmartKey to position 1
in the ignition lock.
X KEYLESS-GO: switch on the ignition.$(USA
only)J(Canada
only)
Check Brake Fluid
Level There is not enough brake fluid in the brake fluid reservoir.
In addition, the $ (USA only)/J (Canada only) warning
lamp lights up in the instrument cluster and a warning tone
sounds.
G WARNING
The braking effect 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 Secure the vehicle against rolling away ( Y page 154).
X Consult a qualified specialist workshop.
X Do not add brake fluid. This does not correct the malfunction. #
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.230
Display messages
On-board computer and displays
Display messages Possible causes/consequences and
M Solutions6
SRS Malfunction
Service Required There is a malfunction in the SRS (Supplemental Restraint
System). The 6 warning lamp also lights up in the instrument
cluster.
G WARNING
The air bags or Emergency Tensioning Devices may either be
triggered unintentionally or, in the event of an accident, may not
be triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop.
Further information on occupant safety (Y page 37). 6
Front Left
Malfunction
Service Required
or Front Right
Malfunction
Service Required SRS has malfunctioned at the front on the left or right. The
6
warning lamp also lights up in the instrument cluster.
G WARNING
The air bags or Emergency Tensioning Devices may either be
triggered unintentionally or, in the event of an accident, may not
be triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop. 6
Left Side Curtain
Malfunction
Service Required
or Right Side
Curtain
Malfunction
Service Required There is a malfunction in the left-hand or right-hand head bag. The
6 warning lamp also lights up in the instrument cluster.
G WARNING
The left or right headbag may either be triggered unintentionally
or, in the event of an accident, may not be triggered.
There is an increased risk of injury.
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 154).
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 ^a indicator
lamp must light up and remain lit. When
the indicator lamp is on, OCS (Occupant Classification System)
has disabled the front-passenger air bag and front-passenger
knee bag ( Y page 43).
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. Display messages
233
On-board computer and displays Z
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 ^a 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 43). 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 154).
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 ^a indicator
lamp in the center console and
the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the ^a indicator
lamp must light up and remain lit. When
the indicator lamp is on, OCS has disabled the front-passenger
air bag and front-passenger knee bag ( Y page 43).
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabled See 234
Display messages
On-board computer and displays
Display messages Possible causes/consequences and
M Solutionsb
Auto
Lamp
Function
Inoperative The light sensor is defective.
X
Visit a qualified specialist workshop. b
Switch Off Lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X
Turn the light switch to Ã. Adaptive Highbeam
Assist Inoperative Adaptive Highbeam Assist is faulty.
X
Visit a qualified specialist workshop. Adaptive Highbeam
Assist Currently
Unavailable See
Operator's Manual Adaptive Highbeam 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.
X Clean the windshield.
If the system detects that the camera is fully operational again,
the Adaptive Highbeam Assist Now Available message is
displayed.
Adaptive Highbeam Assist is operational again. Engine
Display messages Possible causes/consequences and
M Solutions+
Check Coolant
Level See
Operator'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 Add coolant, observing the warning notes before doing so
(Y page 498).
X If coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist
workshop. ? The fan motor is faulty.
X
At coolant temperatures under 248 ‡(120 †), drive
to the next
qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic.238
Display messages
On-board computer and displays
Display messages Possible causes/consequences and
M SolutionsABC is malfunctioning.
The display message is shown continuously.
G WARNING
The suspension tuning characteristics are thus affected.
There is a risk of an accident.
X Do not drive faster than 50 mph (80 km/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 Visit a qualified specialist workshop. À
Attention Assist:
Take a Break! Based on certain criteria, ATTENTION ASSIST has detected fatigue
or
a
lack of concentration on the part of the driver. A warning tone
also sounds.
X If necessary, take a break.
During long journeys, take regular breaks in good time so you get
enough rest. À
Attention Assist
Inoperative ATTENTION ASSIST is inoperative.
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 175). Radar Sensors
Deactivated See
Operator's Manual The radar sensor system is deactivated.
X
Switch on the radar sensor system (Y page 218).242
Display messages
On-board computer and displays
Display messages Possible causes/consequences and
M SolutionsActive Blind Spot
Assist Inoperative 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). Park Assist
Inoperative You have just carried out a large number of turning or parking
maneuvers.
Active Parking Assist will become available again after
approximately ten minutes (
Y page 186).
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Switch off and restart the engine.
If the display message continues to be displayed:
X Visit a qualified specialist workshop. PARKTRONIC is defective.
X
Visit a qualified specialist workshop. Park Assist
Finished The vehicle is parked. A warning tone also sounds.
The display message disappears automatically.
DISTRONIC PLUS
Off DISTRONIC PLUS has been deactivated (
Y page 164).
If it was deactivated automatically, a warning tone also sounds. DISTRONIC PLUS
Now Available DISTRONIC PLUS is operational again after having been
temporarily
unavailable.
You can now reactivate DISTRONIC PLUS
(Y page 164). 244
Display messages
On-board computer and displays