Page 233 of 321

Problem Possible causes/consequences and
M Solutions
֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. G
Risk of accident
ESP ®
,B AS, PRE-SAFE ®
, the HOLD functio nand hill start assist are
temporarily unavailable.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
also have failed.
ESP ®
will not stabilise the vehicle if it starts to ski dorifawheel
starts to spin.
Self-diagnosis is not yet complete.
The brake system continues to function normally, but without the
functions listed above .The wheels could therefore lock if you
brake hard, for example.
ATTENTION ASSIST is deactivated.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements, at a speed above 20 km/h.
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. !
The red indicator lamp
for the electric parking
brake flashes and/or
the yellow warning
lamp for the electric
parking brake lights up.
The electric parking brake is temporarily malfunctioning or is
defective.
X
Observe the additional display messages in the multifunction
display. 6
The red SRS warning
lamp is lit while the
engine is running.
G
Risk of injury
The restraint systems are malfunctioning. The airbags or belt ten-
sioners may either be triggered unintentionally or, in the event of
an accident, may not be triggered at all.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. 230
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 234 of 321

Engine
Problem Possible causes/consequences and
M Solutions
;
The yellow engine diag-
nostics warning lamp
lights up while the
engine is running.
There may be a fault, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system (for vehicles with petrol engines)
R in the fuel system
The emission limit values may be exceeded and the engin emay
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop. Vehicles with a diesel engine: the fuel tan
khas been run dry
(Y page 145).
X Start the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emer-
gency running mode is cancelled. The vehicle need no tbe
checked. 8
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.
The fuel level has dropped into the reserve range.
X
Refuel at the nearest filling station. ?
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature gauge is at the
star toft he scale. The temperature sensor for the coolant temperature gauge is
faulty.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine. Do not continue driving
under any circumstances.
X Engage the electric parking brake.
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
231On-board computer and displays Z
Page 235 of 321

Problem Possible causes/consequences and
M Solutions
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator
may be blocked or the electric engine radiator fan may be mal-
functioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Let the engine and coolant cool down.
X Check the coolant level and top up the coolant (Y page 251).
Observe the warning notes as you do so.
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is less than 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 on
mountain roads and stop-start traffic. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 120 †. The airflow to the
engine radiator may be blocked or the coolant level may be too
low.
The engine is not being cooled sufficiently and may be damaged.
X Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Let the engine and coolant cool down.
X Check the coolant level and top up the coolant (Y page 251).
Observe the warning notes as you do so.
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is less than 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 on
mountain roads and stop-start traffic. 232
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Page 236 of 321

Driving systems
Problem Possible causes/consequences and
M Solutions
·
The red distance warn-
ing lamp lights up while
the vehicle is in motion.
G
Risk of accident
The distance to the vehicle in fron tis too small for the speed
selected.
X Increase the distance. ·
The red distance warn-
ing lamp lights up while
the vehicle is in motion.
Aw
arning tone also
sounds. G
Ris
kofa ccident
You are approaching a vehicle or a stationary obstacle in your line
of travel at too high a speed.
X Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to
brake or take evasive action.
More information about DISTRONIC PLUS (Y page 156) and
PRE-SAFE ®
Brake (Y page 59). Tyres
Problem Possible causes/consequences and
M Solutions
h
The yellow tyre pres-
sure monitor warning
lamp is on.
G
Ris
kofa ccident
The tyre pressure monito rhas detected a loss of pressure in at
least one of the tyres.
X Stop the vehicle without making any sudde nsteering or braking
manoeuvres .Pay attentio nto the traffic conditions as you do
so.
X Observe the additional display messages in the multifunction
display.
X Check the tyre pressure. If necessary, correc tthe tyre pressure
(Y page 292).
X If necessary, change a wheel (Y page 294). Warning and indicator lamps in the instrument cluster
233On-board computer and displays Z
Page 237 of 321
Page 238 of 321
Useful information
............................236
Stowage areas .................................. 236
Features ............................................. 239 235Stowing and features
Page 239 of 321

Useful information
i This Owner's Manual describes all models
and all standard and optional equipment
available to your vehicle at the time of pub-
lication of the Owner's Manual. Country-
specific deviations are possible. Please
note that your vehicle may not be equipped
with all features described. This also
applies to safety-relevan tsystems and
functions.
i Please read the information on qualified
specialist workshops (Y page 22).Stowage areas
Stowage compartments
Important safety notes G
WARNING
The stowage compartments mus tbe closed
when items are stored in them. Luggage nets
are not designed to secure heavy items of
luggage.
You or other vehicle occupants could be
injured by objects being thrown around if you:
R brake sharply
R change direction suddenly
R have an accident
Sharp-edged and fragile objects must not be
carried in the luggage net.
Do not carry hard objects in the ruffled pock-
ets. Objects must not protrude over the top
of the ruffled pockets.
Front stowage compartments Glove compartment
i The glove compartment flap contains
brackets for coins, pens, and credit and
service cards. X
To open: pull handle :and open glove
compartment flap ;.
X To close: fold glove compartment flap ;
upwards until it engages.
The glove compartment can be locked and
unlocked using the key (Y page 66) or using
the emergency key element. X
To lock: insert the emergency key element
into the lock and turn it 90° clockwise to
position 2.
X To unlock: insert the emergency key ele-
ment into the lock and turn it 90° anti-
clockwise to position 1.236
Stowage areasStowing and features
Page 240 of 321

Spectacles compartment
X
To open: press marking :.
Stowage compartment in the centre con-
sole X
To open: briefly press the lower section of
cover :.
X To remove an insert: grip the left-hand
side of the insert and pull it up and out.
X To replace an insert: press the insert into
the casing shell.
i Depending on the vehicle's equipment,
there may be an ashtray in the centre con-
sole instead of the stowage compartment. Stowage compartment in front of the arm-
rest X
To open: slide cover :back.
Stowage compartment/telephone com-
partment under the armrest
i Depending on the vehicle's equipment, a
12 V socket, a USB port, and an AUX-IN
jack or a Media Interface are installed in the
stowage compartment. A Media Interface
is a universal interface for portable audio
equipment, e.g. for an iPod ®
or MP3 player
(see the separate Audio or COMAND Online
operating instructions).
i The stowage compartmen tcan be locked
and unlocked centrally using the key
(Y page 66). X
To open: push button :up and raise arm-
rest ;. Stowage areas
237Stowing and features Z