open bonnet MERCEDES-BENZ E-CLASS CABRIOLET 2012 User Guide

Display messages Possible causes/consequences and
M Solutions
T!
÷
inoperative See
Owner's Manual EBD (electronic brake force distribution), ABS, ESP
®
, BAS, PRE-
SAFE ®
, the HOLD function ,hill start assist and ESP ®
trailer stabi-
lisatio nare unavailable due to a malfunction.
The adaptive brake lights, BAS PLUS and PRE-SAFE ®
Brake may
also have failed.
In addition, the ä,åand! warning lamps light up in
the instrument cluster and a warning tone sounds.
G WARNING
The brake system continues to function normally, but withou tthe
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 Drive on carefully.
X Visit a qualified specialist workshop immediately. J
Release parking
brake You are driving with the parking brake applied.
Awarning tone also
sounds.
X Release the parking brake. J
Brake immediately or
Vehicles with manual transmission
:with the HOL Dfunction acti-
vated, you have either:
R opened the driver's door and released the seat belt or
R switched off the engine or
R opened the bonnet.
At one may also sound at regular intervals. If you attempt to lock
the vehicle, the tone becomes louder.
You cannot start the engine.
X Paying attention to the traffic situation, immediately depress the
brake pedal firmly and hold until the display message disap-
pears.
X Secure the vehicle against rolling away (Y page 177).
You can restart the engine. 252
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
?
Coolant Stop vehi‐
cle Switch engine
off The coolan
tis too hot.
Aw arning tone also sounds.
G WARNING
Never drive with an overheated engine. Driving when your engine
is overheated can cause som efluids which may have leaked into
the engine compartment to catch fire.
Steam fro manoverheated engine can cause serious burns, which
can occur just by opening the bonnet.
This poses a risk of injury.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 177).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Do not start the engine again until the display message goes out
and the coolant temperature is under 120 †. The engine may
otherwise be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visi taqualified specialist
workshop immediately.
The reading may rise up to 120 †undernormal driving conditions
if the coolant has been filled correctly. 260
Display messagesOn-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

Vehicle
Display messages Possible causes/consequences and
M Solutions
To start engine,
shift to either P
or N You have attempted to start the engine with the transmission in
position
Ror D.
X Shift the transmission to position Por N. P
Select Park (P) You have switched off the engine with the Start/Stop button and
opened the driver's door.
You wanted to lock the vehicle.
Aw
arning tone also sounds.
or
You have switched off the engine with the Start/Stop butto nand
opened the driver's door with the transmission in position N.
X Shift the transmission to position P. While the HOLD functio
norDISTRONIC PLUS is active, you have:
R opened the driver's door and released the seat belt or
R switched off the engine or
R opened the bonnet
At one may also sound at regular intervals. If you attempt to lock
the vehicle, the tone becomes louder.
You cannot start the engine.
X Shift the transmission to position P.
You can restart the engine. Without changing
gear,
consult workshop You cannot change the transmission position due to a malfunction.
Aw
arning tone also sounds.
If transmission position Dis selected:
X Drive to a qualified specialist workshop without shifting the
transmission from position D.
If transmission position R,Nor Pis selected:
X Consult a qualified specialist workshop. N The boot lid is open.
X
Close the boot lid. 270
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
M? The bonne
tis open. Awarning tone also sounds.
CLS Shooting Brake: the bonnet is open. A warning tone also
sounds.
G WARNING
The open bonne tmay then bloc kyour view when the vehicle is in
motion.
There is a risk of accident.
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 177).
X Close the bonnet.
If the active bonnet (pedestrian protection) has been triggered:
X Reset the bonnet (Y page 306).
X Close the bonnet. Active bonnet mal‐
function See Own‐
er's Manual The active bonnet (pedestrian protection) is not active due to a
malfunction.
The active bonnet (pedestrian protection) is not active due to a
malfunction or because it has already been triggered.
X Visit a qualified specialist workshop. C At least one door is open.
Awarning tone also sounds.
X Close all doors. _
Rear left seat
backrest not
locked or
Rear right seat back‐
rest not locked The backres
tinthe rear is not engaged on the left-hand and/or
right-hand side. Awarning tone also sounds.
X Push the backres tback until it engages. _
Front left seat
backrest not
locked or
Front right seat back‐
rest not locked The driver's or front-passenger seat backres
tis not engaged. A
warning tone also sounds.
X Push the backrest back until it engages. Display messages
271On-board computer and displays Z

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 Secure the vehicle against rolling away (Y page 177).
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 310).
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 Do not start the engine again until the coolant temperature is
under 120 †. The engine may otherwise be damaged.
X Drive 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. ?
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.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine
is overheated can cause some fluids which may have leaked into
the engine compartment to catch fire.
Steam from an overheated engine can cause serious burns, which
can occur just by opening the bonnet.
This poses a risk of injury.
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 Secure the vehicle against rolling away (Y page 177).282
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos-
sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: (Y page 23). Engine compartment
Bonnet
Active bonnet (pedestrian protection) Operating principle
G
WARNING
If you pull the bonnet release lever and then
neglec tto reset the bonnet, it will not lock at
the front when closed. The bonnet can then
open when the vehicle is in motion and
obscure your field of vision. If you pull the
bonnet release lever, you must reset the bon-
net before driving on.
! Do not try to press down the raised bon-
net at the back. Otherwise, the bonnet
could be damaged.
The active bonnet is only available in certain
countries.
The active bonnet can reduce the risk of injury
to pedestrians in certain accident situations.
Raising the active bonnet increases the clear-
ance to hard components, such as the engine. If active bonnet
:has been triggered, it will
be raised at the back by about 50 mm.
Lids ;will then no longer rest on housings
=.
You can reset a triggered active bonnet your-
self.
Even if the active bonnet has been triggered,
you can still continue driving and have it reset
at a qualified specialist workshop. If you pull
the bonnet release lever, you must reset the
bonnet before driving on.
Resetting G
WARNING
There is a risk of injury if the bonnet is open,
even if the engine is not running.
Some engine components can become very
hot.
To avoid the risk of burns, only touch those
components described in the Owner's Manual
and observe the relevant safety notes. G
WARNING
If the bonnet can still not be engaged properly
or the Lsymbol appears in the multifunc-
tion display, do not continue driving. The bon-
net can then open when the vehicle is in
motion and obscure your field of vision. Con-
sult a qualified specialist workshop. Other-
wise, you may cause an accident and injure
yourself and others. 306
Engine compartmentMaintenance and care

X
Open the bonnet (Y page 307).
X With both hands, lift the bonnet up in the
centre A.The bonnet is open wide enough
when both lids of bonnet lifter ;no longer
move.
If you push the lids back, you will notice a
resistance.
X Release bonnet :.
X Check whether the lids of bonnet lifter ;
are resting on housings =(arrow).
X The lids of bonnet lifter ; are resting
on the housings: close bonnet:
(Y page 308).
or
X The lids of bonnet lifter ; are not rest-
ing on the housings: first lift up bon-
net :on left-hand side ?and then on
right-hand side B. Lift up bonnet :until
the respective lid of bonnet lifter ;no lon-
ger moves.
The lids of bonnet lifter ;must rest on
housings =(arrow).
X Close bonnet :(Ypage 308).
If you cannot close the bonnet :or if the
L symbol appears in the multifunction
display, repeat the steps.
Opening the bonnet G
WARNING
Do not pull the release lever while the vehicle
is in motion. If you do so, the bonnet may open
up and block your view. G
WARNING
There is a risk of injury if the bonnet is open,
even if the engine is not running.
Some engine components can become very
hot.
To avoid the risk of burns, only touch those
components described in the Owner's Manual
and observe the relevant safety notes. G
WARNING
The radiator fan between the radiator and the
engine can start automatically, even if the key
has been removed from the ignition lock. For
this reason, you must not reach into the fan
rotation area. You could otherwise be injured.
Vehicles with apetrol engine: The elec-
tronic ignitio nsystem uses high voltage. For
this reason, you mus tnever touch ignition
system components (ignition coil, ignition
cables, spark plug connectors or test socket)
while:
R the engine is running
R the engine is being started
R the ignition is switched on and the engine
is being cranked by hand
You could otherwise suffer an electric shock
and be seriously or even fatally injured.
Vehicles with adiesel engine: The elec-
tronic injection control uses high voltage. For
this reason, you must never touch injection
system components while:
R the engine is running
R the engine is being started
R the ignition is switched on
You could otherwise suffer an electric shock
and be seriously or even fatally injured. G
WARNING
The windscreen wipers and wiper linkage
could be set in motion.
When the bonnet is open, you or others could
be injured by the wiper linkage.
Make sure that the windscreen wipers are
switched off. Remove the key or make sure Engine compartment
307Maintenance and care
Z

tha
tno ignition position has been selected
with KEYLESS-GO. All indicator lamps must be
off in the instrument panel.
! Make sure that the windscreen wipers are
not folded away from the windscreen. Oth-
erwise, you could damage the windscreen
wipers or the bonnet. X
Make sure that the windscreen wipers are
switched off.
X Pull release lever :on the bonnet.
The bonnet is released. X
Reach into the gap, pull bonnet catch han-
dle ;up and lift the bonnet.
If you lift the bonnet by approximately
40 cm, the bonnet is opened and held open
automatically by the gas-filled strut.
Closing the bonnet G
WARNING
Make sure that nobody can become trapped
as you close the bonnet. X
Lower the bonnet and let it fall from a
height of approximately 20 cm.
X Check that the bonnet has engaged prop-
erly.
If the bonnet can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force. Radiator
Vehicles with adiesel engine: do not cover
the radiator .Do not use thermal mats, insect
protection covers or anything similar. Doing
so can cause the Onboard Diagnostics Sys-
tem to display inaccurate values. Some of
these values are legally required and must
always be correct. Engine oil
General notes Depending on your driving style, the vehicle
consumes up to 0.8 l of oil per 1,000 km. The
oil consumption may be higher than this when
the vehicle is new or if you frequently drive at
high engine speeds.
Depending on the engine, the oil dipstick may
be installed at a different location.
When checking the oil level:
R park the vehicle on a level surface.
R the engine should be switched off for
approximately five minutes if the engine is
at normal operating temperature.
R if the engine is not at normal operating
temperature, e.g. if the engine was only
started briefly: wait about 30 minutes
before carrying out the measurement. 308
Engine compartmentMaintenance and care

i
When you park the vehicle, remove the
key if you do not require any electrical con-
sumers. The vehicle will then use very little
energy, thus conserving battery power.
i After an interruption of the power supply,
e.g. the battery was discharged, you have
to:
R set the clock. Information on setting the
clock can be found in the separate oper-
ating instructions.
On vehicles with COMAND Online and a
navigation system, the clock is set auto-
matically.
R reset the function for folding the exterior
mirrors in/out automatically, by folding
the mirrors out once (Y page 118).Charging the battery
G
WARNING
Only charge the battery in a well-ventilated
area. As the battery is being charged, gases
can escape and generate minor explosions.
This could injure you and other persons or
cause damage to the paintwork or acid cor-
rosion on the vehicle.
You can obtain information on battery charg-
ers which allow the batter yto be charged
while still installed from a qualified specialist
workshop. G
WARNING
There is a risk of acid burns during the charg-
ing process due to the gases which escape
from the battery. Do not lean over the battery
during the charging process. G
WARNING
Battery acid is caustic. Avoid contact with the
skin, eyes or clothing.
! Only charge the installed battery with a
battery charger which has been tested and
approved by Mercedes-Benz. These battery chargers allow the battery to be charged
while still installed in the vehicle.
! Only use battery chargers with a maxi-
mum charging voltage of 14.8 V.
! Only charge the battery using the jump-
start connection point.
The jump-starting connection point is in the
engine compartment (Y page 331).
Read the battery charger's operating instruc-
tions before charging the battery.
X Open the bonnet (Y page 307).
X Connect the battery charger to the positive
terminal and earth point in the same order
as when connecting the donor battery in
the jump-starting procedure
(Y page 331). 330
Battery (vehicle)Breakdown assistance