
Safety systems
Problem Possible causes/consequences and
M Solutions
J
The yellow brake sys-
tem warning lamp
lights up while the
engine is running. G
WARNING
The brake system is malfunctioning and the braking characteris-
tics may be affected.
There is a risk of an accident.
X If the multifunction display shows a display message, please
observe this.
X Drive on carefully.
X Visit a qualified specialist workshop. J
The red brake system
warning lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
G
WARNING
The brake boosting effect is malfunctioning and the braking char-
acteristics may be affected.
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 183).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. J
The red brake system
warning lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
There is insufficient brake fluid in the brake fluid reservoir.
G WARNING
The 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 Secure the vehicle against rolling away (Y page 183).
X Do not top up the brake fluid. Topping up will not rectify the
fault.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. 300
Indicator and warning lamps in the instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
!
The yellow ABS warning
lamp is lit while the
engine is running. ABS (Anti-lock Brake System) has been deactivated due to a fault.
For this reason, BAS (Brake Assist), BAS PLUS, ESP ®
(Electronic
Stability Program), PRE-SAFE ®
,P RE-SAFE ®
Brake ,the HOLD func-
tion, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation are also deactivated, for example.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop.
If the ABS control unit is faulty, there is also a possibility that other
systems, such as the navigation system or the automatic trans-
mission, will not be available. Indicator and warning lamps in the instrument cluster
301On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
!
The yellow ABS warning
lamp is lit while the
engine is running. A
warning tone also
sounds. EBD is not available due to a malfunction. Therefore, ABS, BAS,
BAS PLUS, ESP
®
, PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD func-
tion, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation, for example, are not available either.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock if you brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. Jäå!
The red brake warning
lamp, the yellow ESP
®
and ESP ®
OFF warning
lamps and the yellow
ABS warning lamp are
lit while the engine is
running. ABS and ESP
®
are not available due to a fault. Therefore, BAS, BAS
PLUS, EBD,P RE-SAFE®
,P RE-SAFE ®
Brake, the HOLD function, hill
start assist, the adaptive brake lights and ESP ®
trailer stabilisa-
tion, for example, are no tavailable either.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock if you brake hard, for example.
The steerability and braking characteristics may be severely affec-
ted. The braking distance in an emergency braking situation can
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The dange rofskidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visi taqualified specialist workshop. 302
Indicator and warning lamps in the instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
äå
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
, BAS, BAS PLUS, PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD
function, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation are not available due to a malfunction.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance in an emergency braking situation can thus
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. J
The red brake system
warning lamp comes on
while the vehicle is
moving. A warning tone
also sounds.
You are driving with the parking brake applied.
X
Release the parking brake.
The warning lamp goes out and the warning tone ceases. 6
The red SRS warning
lamp is lit while the
engine is running.
There is a malfunction in the SRS (Supplemental Restraint Sys-
tem).
G WARNING
The airbags or belt tensioners may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
This poses an increased risk of injury.
X Drive on carefully.
X Have SRS checked at a qualified specialist workshop immedi-
ately.
For further information about the Supplemental Restraint System,
see (Y page 43). 304
Indicator and warning lamps in the instrument clusterOn-board computer and displays

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 182).
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.
Operation of the auxiliary heating is deactivated if the fuel level
drops 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 Secure the vehicle against rolling away (Y page 183).
X Consult a qualified specialist workshop. Indicator and warning lamps in the instrument cluster
305On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
X
Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and top up the coolant, observing the
warning notes (Y page 348).
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 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
mountainous terrain and stop-start traffic. Driving systems
Problem Possible causes/consequences and
M Solutions
·
The red distance warn-
ing lamp lights up while
the vehicle is in motion.
The distance to the vehicle in front is 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. 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.
Further information on DISTRONIC PLUS (Y page 195).
Further information on PRE-SAFE ®
Brake (Y page 76). Indicator and warning lamps in the instrument cluster
307On-board computer and displays Z

X
To open: pull handle :up and fold
cover ;forwards.
i On vehicles with a fire extinguisher, the
fire extinguisher is located in the stowage
compartment under the driver's seat.
Stowage compartmen tin the rear com-
partment Vehicles with a rear bench seat
X
To open: fold down seat armrest ;.
X Fold cover :of the armrest upwards. Vehicles with luxury single seats in the rear com-
partment X
Pull handle :upwards.
The armrest folds out.
Stowage net in the rear compartment Vehicles with a rear bench seat
:
Stowage net Vehicles with luxury single seats in the rear com-
partment
:
Handle strip
; Stowage net
X Pull handle strip :on the upper edge of
the cover forwards until it is released from
its anchorage.
X Fold down the cover in the direction of the
arrow. Stowage nets
G
WARNING
Only place lightweight items in the luggage
net. Do not use it to transport heavy, bulky,
sharp-edged or fragile objects. In the event of Stowage areas
313Stowing and features
Z

The left-hand and right-hand rear seat backr-
ests can be folded down separately to
increase the boot capacity.
Folding the seat backrest forwards
!
Before you fold down the rear seat back-
rest, remove the side head restraints for
the integrated child seat; see the "Side
head restraints for integrated child seat"
section. The side head restraints could oth-
erwise be damaged. i
Vehicles with memory function: when you
fold one or both parts of the rear seat back-
rest forwards, the respective fronts eat
moves forward slightly, when necessary, in
order to avoid contact.
X Vehicles without memory function: if nec-
essary, move the driver's or front-
passenger seat forwards.
X Open the boot.
X Pull right-hand or left-hand rear seat back-
rest release handle :.
The corresponding rear seat backrest is
released.
The head restraints for the seat backrests
in the rear compartment lower. X
Fold rear seat backrest ;forwards.
X Move the driver's or front-passenger seat
back if necessary.
Folding back the seat backrest G
WARNING
Make sure that the rear seat backrest is cor-
rectly engaged. Otherwise, vehicle occupants
could be injured by objects being thrown
around if you:
R brake sharply
R change direction suddenly
R are involved in an accident
If the rear seat backrest is not engaged, this
will be shown in the multifunction display in
the instrument cluster.
! Make sure that the seat belt does not
become trapped when folding the rear seat
backrest back. Otherwise, it could be dam-
aged. 316
Stowage areasStowing and features