2012 MERCEDES-BENZ E-CLASS CABRIOLET battery

Problem Possible causes/consequences and
M Solutions
The fuel filler flap can-
not be opened. The fuel filler flap is not unlocked.
or
The key battery is discharged.
X
Unlock the vehicle (Y page 77).
or
X Unlock the vehicle using the emergency key element
(Y page 78). The fuel filler flap is unlocked, but the opening mechanism is jam-
med.
X
Consult a qualified specialist workshop. Parking
Important safety notes
G
WARNING
If flammable materials such as leaves, grass
or twigs are exposed to prolonged contact to
parts of the exhaust system that heat up, they
could ignite. There is a risk of fire.
Park the vehicle so that no flammable mate-
rials come into contact with parts of the vehi-
cle which are hot. Take particular care not to
park on dry grassland or harvested grain
fields. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect,
for example, the power steering and the brake
boosting effect.Y ou will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving. G
WARNING
If you leave children unattended in the vehi-
cle, they could set the vehicle in motion by,
for example:
R releasing the parking brake
R shifting an automatic transmission out of
parking position P
R shifting a manual transmission into neutral
R starting the engine
They could also operate vehicle equipment.
There is a risk of an accident and injury.
When leaving the vehicle, always take the key
with you and lock the vehicle. Never leave
children unattended in the vehicle.
! Am oving vehicle can lead to damage to
the vehicle or damage to the drive train.
To ensure that the vehicle is secured against
rolling away unintentionally:
R the parking brake must be applied.
R on vehicles with manual transmission,
engage first gear or reverse gear.
R on vehicles with automatic transmission,
the transmission must be in position Pand
the key must be removed from the ignition
lock.
R on uphill or downhill gradients, the front
wheels must be turned towards the kerb. Parking
177Driving and parking Z

Parking up the vehicle
If you leave the vehicle parked up for longer
than four weeks, the battery may be damaged
by exhaustive discharging.
If you leave the vehicle parked up for longer
than six weeks, the vehicle may suffer dam-
age as a result of lack of use.
X Visit a qualified specialist workshop and
seek advice.
i You can obtain information about trickle
chargers from a qualified specialist work-
shop. Driving tips
General notes
G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect,
for example, the power steering and the brake
boosting effect.Y ou will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving. ECO display
ECO display (example)
The ECO display gives you information on how
economical your driving style is. The ECO dis-
play assists you in achieving the optimum
driving style in terms of consumption, taking
the actual and selected conditions into con-
sideration. Your driving style can significantly
influence the vehicle's consumption. The ECO display consists of three bars:
R
Acceleration
R Constant
R Coasting
The percent value is the average value of the
three bars. The three bars and the average
value commence with a value of 50%. Ahigher
percentage indicates a mor eeconomical driv-
ing style.
The ECO display provides no information on
the actual fuel consumption. Afixed percent-
age value of the ECO display does not corre-
spond to a fixed consumption figure in
l/100km.
Apart from driving style, consumption is
dependent on many factors such as:
R load
R tyre pressure
R cold start
R selected route
R number of consumers that are switched on
These variable are not included in the ECO
display.
Your driving style is evaluated on the basis of
the following three categories:
Acceleration (evaluation of all accelera-
tion processes) The bar fills up: The bar depletes:
Moderate accelera-
tion, espeically at
higher speeds Sporty acceleration
Constant (evaluation of the driving style
at any point in time)
The bar fills up: The bar depletes:
Constan
tspeed and
avoidance of unnec-
essary acceleration
and deceleration
processes Fluctuations in
speed Driving tips
179Driving and parking Z

DISTRONIC PLUS must also never be oper-
ated, activated or deactivated by a passenger
or fro moutside the vehicle.
DISTRONIC PLUS does not replace the park-
ing brake and must not be used for parking.
The DISTRONIC PLUS braking effect is can-
celled and the vehicle can start moving if:
R DISTRONIC PLUS is deactivated using the
cruise control lever.
R you accelerate.
R there is a malfunction in the system or an
interruption in the power supply, e.g .bat-
tery failure.
R the electrical system in the engine com-
partment, the battery or the fuses are tam-
pered with.
R the battery is disconnected.
If you wish to leave th evehicle or park it,
deactivate DISTRONIC PLUS and secure the
vehicle against rolling away.
If DISTRONIC PLUS detects that the vehicle
in fron tis stopping, it brakes your vehicle until
it is stationary.
Once your vehicle is stationary, it remains
stationary and you do not need to depress the
brake.
i Depending on the specified minimum dis-
tance, your vehicle will come to a standstill
at a sufficient distance behind the vehicle
in front.T he specified minimum distance is
set using the control on the cruise control
lever.
You will see a warning message in the multi-
function display if DISTRONIC PLUS is acti-
vated and:
R the driver's door is open and the driver's
seat belt is unfastened.
R the engine is switched off, unless it is auto-
matically switched off by the ECO start/
stop function.
R the bonnet is opened.
Select Park (P) X
Shift the transmission to position Pto pre-
vent the vehicle from rolling away.
DISTRONIC PLUS is deactivated. The warn-
ing message in the multifunction display
disappears.
The horn will also sound at regular intervals if
DISTRONIC PLUS is activated and you:
R switch the engine off, open the driver's
door and take off your seat belt
R open the bonnet
The sounding of the horn alerts you to the fact
that the vehicle has been parked while DIS-
TRONIC PLUS is still activated. The sound
becomes louder if you attempt to lock the
vehicle. The vehicle is not locked until DIS-
TRONIC PLUS is deactivated.
i If the engine has been switched off, it
cannot be started again until DISTRONIC
PLUS has been deactivated.
If DISTRONIC PLUS is activated and a fault
occurs in the system or if there is a disruption
in the power supply, the Brake immedi‐ ately message is shown in the multifunction
display. Immediately depress the brake firmly
until the warning message in the multifunc-
tion display goes out or shift the transmission
to position P. DISTRONIC PLUS is deactiva-
ted.
Setting aspeed X
Press the cruise control lever up :for a
highe rspeed or down ;for a lower speed.
X Keep the cruise control lever pressed until
the desired speed is reached. Driving systems
193Driving and parking Z

HOLD function
General notes The HOLD function can assist the drive
rinthe
following situations:
R when pulling away, especially on steep
slopes
R when manoeuvring on steep slopes
R when waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
The braking effect is cancelled and the HOLD
function is deactivated when you depress the
accelerator pedal to pull away.
Activation conditions You can activate the HOLD function if:
R
the vehicle is stationary.
R the engine is running or if it has been auto-
matically switched off by the ECO start/
stop function.
R the driver's door is closed or if your seat
belt is fastened.
R the parking brake is released.
R the bonnet is closed.
R the selector lever is in position D,Ror Non
vehicles with automatic transmission.
R DISTRONIC PLUS is deactivated.
Activating the HOLD function G
WARNING
The vehicle's brakes are applied when the
HOLD function is activated. For this reason,
deactivate the HOLD function if the vehicle is
to be set in motion by other means (e.g. in a
car wash or by towing). X
Make sure that the activation conditions
are met.
X Depress the brake pedal.
X Quickly depress the brake pedal further
until ë appears in the multifunction dis-
play.
The HOLD function is activated. You can
release the brake pedal.
i If depressing the brake pedal the first
time does not activate the HOLD function,
wait briefly and then try again.
Deactivating the HOLD function G
WARNING
Never get out of the vehicle when the HOLD
function is activated.
The HOLD function must never be operated
or deactivated by a passenger or from outside
the vehicle.
The HOLD function does not replace the park-
ing brake and must not be used for parking.
The braking effect of the HOLD function is
cancelled and the vehicle could roll away if:
R the HOLD function is deactivated by
depressing the accelerator pedal or the
brake pedal.
R there is a malfunction in the system or an
interruption in the power supply, e.g. bat-
tery failure.
R the electrical system in the engine com-
partment, the battery or the fuses are tam-
pered with.
R the battery is disconnected.
If you leave the vehicle or park it, deactivate
the HOLD function and secure the vehicle
against rolling away.
The HOLD function is deactivated automati-
cally if:
R you accelerate. On vehicles with automatic
transmission: only when the transmission
is in position Dor R.
R you shift the transmission to position Pon
vehicles with automatic transmission. 198
Driving systemsDriving and parking

X
Place the protective covering on the ball
coupling. The release wheel is located behind the left-
hand side trim panel in the boot.
To open the cover:
X
Turn handle :anti-clockwise and fold
down cover ;. To release and lower the ball coupling:
X Pull out release wheel ?.
X Turn release wheel ?anti-clockwise.
The ball coupling unlocks and lowers. Indi-
cator lamp =flashes. X
Press the ball coupling in the direction of
the arrow until it engages behind the
bumper.
Indicator lamp =goes out and the mes-
sage in the multifunction display disap-
pears.
i Fold the ball coupling back in if you are
not using the trailer tow hitch. Trailer power supply
! You can connect accessories with a
power rating of up to 240 W to the perma-
nent power supply and with a power rating
of up to 180 W to the power supply that is
switched on via the ignition lock.
The trailer battery may not be charged from
the power supply.
X To switch the connected power supply
on or off: turn the key in the ignition lock
to position 2or 0respectively
(Y page 159).
When it leaves the factory, your vehicle's
trailer socket is equipped with a permanent
power supply and a power supply that is
switched on via the ignition lock.
The permanen tpower supply is supplied via
trailer socket pin 9.
The power supply that is switched on via the
ignition lock is supplied via trailer socket pin
10.
The trailer's permanent power supply is
switched off in the event of low vehicle supply
voltage and after six hours at the latest.
You can find more information about instal-
ling the trailer electric sataqualified special-
ist workshop. Bulb failure indicator for LED lamps
i If LED lamps are fitted in the trailer, an
error message may appear in the multi-
function display even if there is no fault. The
reason for the error message could be that 224
Towing
atrailerDriving an d parking

X
Press the 9or: button to select
Radar sensor (See Owner's Man.): .
You will see the selected setting: on or
off .
X Press the abutton to save the setting.
i You must deactivate the radar sensor sys-
tem in certain countries and near radio
telescope facilities. For further informa-
tion, see (Y page 382).
When you are close to radio telescope facili-
ties, the radar sensor system will be deacti-
vated automatically.
The following systems are switched off when
the radar sensor system is deactivated:
R DISTRONIC PLUS (Y page 188)
R BAS PLUS (Y page 65)
R PRE-SAFE ®
Brake (Y page 69)
R Blind Spot Assist (Y page 210)
R Active Blind Spot Assist (Y page 214)
Heating Auxiliary heating departure time
G
WARNING
Exhaust fumes are produced when the auxili-
ary heating is in operation. Inhaling these
exhaust fumes can be poisonous. You should
therefore switch off the auxiliary heating in
confined spaces without an extraction sys-
tem, e.g. a garage. G
WARNING
When operating the auxiliary heating parts of
the vehicle can get very hot. Make sure that
the exhaust system does not under any cir-
cumstances come into contact with easily
ignitable material such as dry grass or fuels.
The material could otherwise ignite and set
the vehicle alight. Choose your parking spot
accordingly.
Operating the auxiliary heating is thus pro-
hibited at filling stations or when your vehicle
is being refuelled. You must therefore switch
off the auxiliary heating at filling stations. !
Operating the auxiliary heating/ventila-
tion draws on the vehicle battery. After you
have heated or ventilated the vehicle a
maximum of two times, drive for a longer
distance.
This function is only available on vehicles with
auxiliary heating (Y page 149).
In the Heating submenu, you can select a
stored departure time or change a departure
time.
The auxiliary heating timer function calcu-
lates the switch-on time according to the out-
side temperature so that the vehicle is pre-
heated by the departure time. When the
departure time is reached, the auxiliary heat-
ing continues to heat for a further five
minutes and then switches off. The auxiliary
heating adopts the THERMATIC or
THERMOTRONIC temperature setting.
You can switch off the auxiliary heating by
using the remote control or the auxiliary heat-
ing button on the centre console.
i Switch the auxiliary heating on regularly
once a month for about ten minutes.
Selecting the departure time or deactivat-
ing a selected departure time
X Press the =or; button on the steer-
ing wheel to select the Settings menu.
X Press the :or9 button to select the
Heating submenu.
X Press ato confirm.
You will see the selected setting.
X Press ato confirm.
X Press the :or9 button to select
one of the three departure times or Timer off (no timer active).
X Press ato confirm.
If a departure time is selected, the yellow
indicator lamp lights up on the auxiliary
heating button. 246
Menus and submenusOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
# The battery is no
tbeing charged.
Aw arning tone also sounds.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
X Stop the vehicle immediately, paying attentio ntoroad and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 177).
X Open the bonnet.
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 OK:
X Visit a qualified specialist workshop. 4
Check eng. oil
lev. when next
refuelling The engine oil level has dropped to the minimum level.
Aw
arning tone also sounds.
X Chec kthe oil level when next refuelling, at the latest
(Y page 309).
X If necessary, top up the engine oil (Y page 309).
X Have the engine checked at a qualified specialist workshop if
the engine oil needs topping up more often than usual. 8
Reserve fuel level The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated when the fuel level
drops into the reserve range.
X
Refuel at the nearest filling station. C There is only a very small amount of fuel in the fuel tank.
The auxiliary heating cannot be operated.
X
Refuel at the nearest filling station without fail. Display messages
261On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
j
Check trailer
hitch lock The trailer tow hitch is no
tcorrectly engaged.
Aw arning tone also sounds.
X Stop the vehicle immediately, paying attentio ntoroad and traf-
fic conditions, and switch off the engine.
X Apply the parking brake.
X Allow the trailer tow hitch ball coupling to engage in the end
position (Y page 222). &
inoperative Bat‐
tery low The on-board voltage is too low. The auxiliary heating has switched
itself off or cannot be switched on (Y
page 149).
X Drive for a longer distance.
The battery is being charged. The auxiliary heating is operational
again as soon as the on-board electrical system voltage is suf-
ficient. &
inoperative
Refuel
vehicle There is too little fuel in the fuel tank.T
he auxiliary heating cannot
be switched on (Y page 149).
X Refuel at the nearest filling station. &
inoperative See
Owner's Man. The auxiliary heating has a temporary malfunction or is faulty.
X
When the vehicle is on alevel surface and the engine has cooled
down, make up to four attempts to switch on the auxiliary heat-
ing, waiting several minutes between each attempt
(Y page 149).
X If the auxiliary heating does not switch on, consult a qualified
specialist workshop. J
Close boot separa‐
tor Cabriolet: the boot separator is open.
X
Close the boot separator (Y page 99).Ð
Power
steering mal‐
function See Own‐
er's Manual The power steering assistance is faulty.
Aw
arning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a ris kofaccident.
X Check whethe ryou are able to apply the extra force required.
X If you are able to steer safely: carefully drive on to a qualified
specialist workshop.
X If you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop. 272
Display messagesOn-board computer and displays