Page 217 of 320

Display messages
Possible causes/consequences and
M Solutions6
SRS Malfunction:
Service Required The restraint system is faulty. In addition, the
6 warning lamp
lights up in the instrument cluster.
G WARNING
The air bags or Emergency Tensioning Devices may either be trig-
gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
X Have the restraint system and its components checked immedi-
ately at a qualified specialist workshop.
Further information on the restraint system and its components can
be found under "Occupant safety" (Y page 46). 6
Front Left Malfunc‐
tion: Service
Required
or Front
Right Malfunction:
Service Required The front left or right restraint system is malfunctioning. In addition,
the 6 warning lamp lights up in the instrument cluster.
G WARNING
The air bags or Emergency Tensioning Devices may either be trig-
gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
X Have the restraint system and its components checked immedi-
ately at a qualified specialist workshop. 6
Left Curtain Air‐
bag Malfunction:
Service Required
or
Rt. Curtain Airbag
Malfunction: Ser‐
vice Required There is a malfunction in the left or right window curtain air bag. In
addition, the 6 warning lamp lights up in the instrument cluster.
G WARNING
The left or right window curtain air bag may either be triggered unin-
tentionally or, in the event of an accident, may not be triggered.
There is an increased risk of injury.
X Have the restraint system checked immediately at a qualified
specialist workshop. Display messages (vehicles with steering wheel buttons)
215
On-board computer and displays Z
Page 218 of 320

Lights
Display messages
Possible causes/consequences and
M Solutionsb
Check Left Low Beam
or
Check Right Low
Beam The left or right-hand low-beam headlamp is faulty.
X
Change the bulb ( Y page 105).b
Check Trailer Left
Turn Signal
or
Check Trailer
Right Turn Signal The left or right-hand trailer turn signal lamp is faulty.
X
Change the bulb (see the trailer manufacturer's operating instruc-
tions). b
Check Trailer
Brake Lamp The trailer brake lamp is faulty.
X Change the bulb (see the trailer manufacturer's operating instruc-
tions). b
Check Trailer Left
Tail Lamp
or Check
Trailer Right Tail
Lamp The left or right-hand trailer tail lamp is faulty.
X Change the bulb (see the trailer manufacturer's operating instruc-
tions). b
Auto Lamp Function
Inoperative The light sensor is faulty. The automatic headlamp feature is mal-
functioning.
X
Switch the light functions on/off manually (Y page
99).
X Visit a qualified specialist workshop. b
Check Rear Left
Turn Signal
or
Check Rear Right
Turn Signal The rear left-hand or rear right-hand turn signal is faulty.
X Change the bulb (Y page 105).b
Check Front Left
Turn Signal
or
Check Front Right
Turn Signal The front left-hand or front right-hand turn signal is faulty.
X Change the bulb (Y page 105).b
Check Center Brake
Lamp The high-mounted brake lamp is faulty.
X
Visit a qualified specialist workshop.216
Display messages (vehicles with steering wheel buttons)
On-board computer and displays
Page 219 of 320

Display messages
Possible causes/consequences and
M Solutionsb
Check Left Tail
and Brake Lamps
or
Check Right Tail
and Brake Lamps The left or right-hand tail lamp/brake lamp is faulty.
X Change the bulb (Y page 105).b
Check Left High
Beam
or Check
Right High Beam The left or right-hand high-beam headlamp is faulty.
X
Change the bulb ( Y page 105).b
License Plate Lamp The left or right-hand license plate lamp is faulty.
X Visit a qualified specialist workshop. b
Switch Off Lights The lights are still switched on when you leave the vehicle. An addi-
tional warning tone sounds.
X Turn the light switch to à or $.b
Check Left Fog Lamp
or
Check Right Fog
Lamp The left-hand or right-hand front fog lamp is faulty.
X Visit a qualified specialist workshop. b
Rear Fog Lamp The rear fog lamp is faulty.
X Change the bulb (Y page
105).b
Check Front Left
Parking Lamp or
Check Front Right
Parking Lamp The front left or front right parking lamp or standing lamp is faulty.
X Change the bulb ( Y page
105).b
Backup Light The left or right-hand back-up lamp is faulty.
X Change the bulb (Y page
105).b
Check Left Tail
Lamp
or Check
Right Tail Lamp The left or right-hand tail lamp is faulty.
X Change the bulb (Y page 105).b
Malfunction See
Operator's Manual The exterior lighting is faulty.
X Visit a qualified specialist workshop. Display messages (vehicles with steering wheel buttons)
217
On-board computer and displays Z
Page 220 of 320
Display messages
Possible causes/consequences and
M SolutionsVehicles with trailer tow hitch: a fuse may be defective.
X Check the fuses and if necessary replace any blown fuses (see
the "Fuse allocation" supplement).
X If the display message does not disappear, consult a qualified
specialist workshop. b
Check Left Daytime
Running Light or
Check Rt. Daytime
Running Light The left or right-hand daytime running lamp is faulty.
X Change the bulb (Y page 105).218
Display messages (vehicles with steering wheel buttons)
On-board computer and displays
Page 221 of 320

Engine
Display messages
Possible causes/consequences and
M Solutions# An additional warning tone sounds. The battery is not being
charged.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
! Do not drive any further. Otherwise the engine may overheat.
X Secure the vehicle to prevent it from rolling away ( Y page 138).
X Consult a qualified specialist workshop. ?
Coolant Too Hot:
Stop Vehicle Turn
Engine Off An additional warning tone sounds. The coolant is too hot.
G WARNING
Never drive with an overheated engine. Driving when the engine is
overheated can cause 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 hood.
There is a risk of injury.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Secure the vehicle to prevent it from rolling away ( Y page
138).
X Wait until the engine has cooled down.
X Make sure that the air supply to the radiator is not obstructed, by
frozen slush for example.
X Do not start the engine again until the display message goes out
and the coolant temperature is below the maximum value speci-
fied. The engine could otherwise be damaged.
X Monitor the ? coolant temperature gauge in the instrument
cluster.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and at the correct coolant level,
the display may rise to the red mark. Display messages (vehicles with steering wheel buttons)
219
On-board computer and displays Z
Page 222 of 320

Display messages
Possible causes/consequences and
M Solutions? The fan motor is faulty.
X Check the ? coolant temperature gauge in the instrument
cluster.
If the coolant temperature is below the maximum value specified
below, you can continue driving to the nearest qualified specialist
workshop.
Avoid heavy loads on the engine, e.g. driving in mountainous ter-
rain, and stop-start traffic.
Under normal operating conditions and at the correct coolant level,
the display may rise to the red mark. +
Check Coolant
Level See Oper.
Manual The coolant level is too low.
! Avoid longer journeys when there is insufficient coolant in the
engine cooling system. You could otherwise damage the engine.
X Add coolant, making sure to observe the warning notes
(Y page 253).
X Have the engine cooling system checked at a qualified specialist
workshop if the coolant needs to be refilled more often than
usual. 4
Check Engine Oil
At Next Refueling X
Check the oil level at the latest when next refueling
(Y page
252).
X If necessary, add engine oil (Y page
253).
X Have the engine checked at a qualified specialist workshop if you
need to add engine oil more often than usual.
! Avoid longer journeys when there is insufficient engine oil. You
could otherwise damage the engine. 4
Manually Check Oil
Level Reminder to check the oil level.
X Check the oil level at the latest when next refueling
(Y page
252).
X If necessary, add engine oil (Y page
253).
X To confirm the oil check: press a.
! Avoid longer journeys when there is insufficient engine oil. You
could otherwise damage the engine. 4
Eng. Oil Level
Low: Stop Vehicle
Turn Engine Off The 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 Secure the vehicle to prevent it from rolling away ( Y page
138).
X Check the oil level ( Y page
252).
X If necessary, add engine oil (Y page
253).220
Display messages (vehicles with steering wheel buttons)
On-board computer and displays
Page 223 of 320

Display messages
Possible causes/consequences and
M Solutionsæ
Fuel Level Low The fuel level has dropped to the reserve range.
X Refuel at the nearest gas station. Ï There is very little fuel in the fuel tank.
X Refuel at the nearest gas station without fail. Driving systems
Display messages
Possible causes/consequences and
M Solutions120 km/h!
Maximum Speed
Exceeded Only for certain countries: the maximum speed has been exceeded.
X Drive more slowly. À
Attention Assist
Inoperative ATTENTION ASSIST has failed.
X Visit a qualified specialist workshop. 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. An additional
warning tone sounds.
X If necessary, take a break.
During long journeys, take regular breaks in good time so that you
get enough rest. Park Assist Can‐
celed Additionally, a warning tone sounds. The active parking assistance
has been canceled and the Active Parking Assist will end automati-
cally. For example, you have touched the steering wheel or driven
too fast.
X Steer and brake yourself.
X If necessary, repeat the parking procedure. Observe the deactiva-
tion conditions as you do so ( Y page
163).Park Assist Inoper‐
ative PARKTRONIC is malfunctioning or faulty.
X Follow the instructions and helpful hints in the "Problems with
PARKTRONIC" section
(Y page 159).
X If the display message continues to be shown, consult a qualified
specialist workshop. Active Parking Assist is unavailable or faulty.
X Switch off the ignition.
X Start the engine again.
X If the display message continues to be shown or symbol j is not
shown in the display, consult a qualified specialist workshop. Display messages (vehicles with steering wheel buttons)
221
On-board computer and displays Z
Page 224 of 320

Display messages
Possible causes/consequences and
M SolutionsCollision Preven‐
tion Assist Inoper‐
ative COLLISION PREVENTION ASSIST PLUS is not available due to a mal-
function.
X Visit a qualified specialist workshop. Collision Preven‐
tion Assist Cur‐
rently Unavail.
See Oper. Manual COLLISION PREVENTION ASSIST PLUS is temporarily inoperative.
Possible causes:
R The sensors in the front bumper are dirty.
R The function is impaired due to heavy rain or snow.
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 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 and COLLISION PREVENTION ASSIST is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle, paying attention to road and traffic
conditions.
X Secure the vehicle to prevent it from rolling away (Y page 138).
X Switch off the engine.
X Clean the sensors in the front bumper (Y page
267).
X Restart the engine. Lane Keeping
Assist Inoperative Lane Keeping Assist is faulty.
X Visit a qualified specialist workshop. Lane Keeping
Assist Currently
Unavail. See Oper.
Manual Lane Keeping Assist is deactivated and temporarily inoperative.
Possible causes:
R The windshield is dirty in the camera's field of vision.
R Visibility is impaired due to heavy rain, snow or fog.
R There are no lane markings for an extended period.
R The lane markings are worn away, dark or covered, e.g. by dirt or
snow.
Once the causes listed above no longer apply, the display message
goes out and Lane Keeping Assist is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle, paying attention to road and traffic
conditions.
X Secure the vehicle to prevent it from rolling away (Y page
138).
X Clean the windshield.222
Display messages (vehicles with steering wheel buttons)
On-board computer and displays