heating MERCEDES-BENZ E-CLASS CABRIOLET 2015 Service Manual

Display messages
Possible causes/consequences and
M
MSolutions #
See Owner's Manual See Owner's Manual The battery is not being charged.
A warning tone also sounds.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
! Do not continue driving. The engine could otherwise overheat.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 157).
X Consult a qualified specialist workshop. #
Stop vehicle See Stop vehicle See
Owner's Manual Owner's Manual The battery is no longer being charged and the battery charge level is
too low.
A warning tone also sounds.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Safeguard the vehicle against rolling away (Y page 157).
X Observe the instructions in the #See SeeOwner's
Owner's Manual
Manualdisplay
message.
X Consult a qualified specialist workshop. 4
Check Check
eng.
eng.oil
oillev.
lev.
when
when next
nextrefuelling
refuelling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
! Avoid long journeys when there is too little coolant in the cooling
system. Otherwise the engine will be damaged.
X Check the oil level when next refuelling, at the latest (Y page 291).
X If necessary, top up the engine oil (Y page 292).
X Have the engine checked at a qualified specialist workshop if the
engine oil needs topping up more often than usual.
Information on approved engine oils can be obtained from any quali-
fied specialist workshop or on the Internet at http://bevo.mercedes-
benz.com. 8
Reserve fuel level Reserve fuel level 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. C There is very little fuel in the fuel tank.
The auxiliary heating cannot be operated.
X Refuel at the nearest filling station without fail. Display
messages
239On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions j
Check Check
trailer
trailer hitch
hitch
lock
lock The trailer tow hitch is not correctly engaged.
A warning tone also sounds.
G WARNING
If the ball coupling is not engaged, the trailer may come loose. There
is a risk of an accident.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Apply the parking brake.
X Engage the trailer coupling's ball coupling in the end position
(Y page 210). &
inoperative inoperative
Battery
Battery
Low
Low The on-board voltage is too low. The auxiliary heating has switched
itself off or cannot be switched on (Y page 132).
X Drive for a considerable distance.
The battery charges. The auxiliary heating is operational again as
soon as the on-board electrical system voltage is sufficient. &
inoperative Refuel inoperative Refuel
vehicle vehicle There is too little fuel in the fuel tank. The auxiliary heating cannot be
switched on (Y page 132).
X Refuel at the nearest filling station. &
inoperative inoperative
See
SeeOwn‐
Own‐
er's Man.
er's Man. The auxiliary heating is temporarily malfunctioning or faulty.
X When the vehicle is on a level surface and the engine has cooled
down, make up to four attempts to switch on the auxiliary heating,
waiting several minutes between each attempt (Y page 132).
X If the auxiliary heating does not switch on, consult a qualified spe-
cialist workshop. Telephone Telephone
No
Noservice
service Your vehicle is outside the network provider's transmitter/receiver
range.
X Wait until the mobile phone operational readiness symbol appears
in the multifunction display. Ð
Power steering mal‐ Power steering mal‐
function See Own‐ function See Own‐
er's Manual er's Manual The power steering assistance is faulty.
A warning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a risk of an accident.
X Check whether you 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. Display
messages
251On-board computer and displays Z

Engine
Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
MSolutions ;
N
The yellow engine diagnostics warning lamp lights up while the engine is run-
ning.
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 engine may be running in
emergency mode.
X Consult a qualified specialist workshop immediately.
Vehicles with a diesel engine: the fuel tank has been run dry (Y page 157).
X After refuelling start the engine three to four times.
If the yellow engine diagnostics warning lamp goes out, emergency running
mode is cancelled. You do not need to have the vehicle checked. 8
N
The yellow reserve fuel warning lamp is on while the engine is running.
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. ?
N
The red coolant warning lamp lights up while the engine is running and the
coolant temperature gauge is at the start of the 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 traffic conditions,
and switch off the engine. Do not continue driving under any circumstances.
X Safeguard the vehicle against rolling away (Y page 157).
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
259On-board computer and displays Z

X
To open: pull cover ;out by its top edge.
X To remove the insert: press release button
= and lift the insert up and out.
X To fit the insert: fit insert:into the holder
from above and press down into the holder
until it engages. Cigarette lighter
Important safety notes G
WARNING
You can burn yourself if you touch the hot
heating element or the socket of the cigarette lighter.
In addition, flammable materials can ignite if:
R the hot cigarette lighter falls
R a child holds the hot cigarette lighter to
objects, for example
There is a risk of fire and injury.
Always hold the cigarette lighter by the knob.
Always make sure that the cigarette lighter is
out of reach of children. Never leave children unattended in the vehicle.
Your attention must always be focused on the
traffic conditions. Only use the cigarette lighter when road and traffic conditions permit.
Cigarette lighter in the front compart-
ment Example: vehicles with automatic transmission X
Turn the key to position 2in the ignition lock
(Y page 139).
X To open: slide cover :forwards until it
engages.
X Press in cigarette lighter ;.
Cigarette lighter ;will pop out automatically
when the heating element is red-hot.
X To close: briefly press cover :at the front.
The cover retracts. 12 V sockets
General notes X
Turn the key to position 1in the ignition lock
(Y page 139).
The sockets can be used for accessories with a
maximum draw of 180 W(15 A). Accessories
include such items as mobile phone chargers.
If you use the sockets for long periods when the engine is switched off, the battery may dis-
charge.
An emergency cut-off ensures that the on-boardvoltage does not drop too low. If the on-board
voltage is too low, the power to the sockets is
automatically cut. This ensures that there is suf-
ficient power to start the engine.
Socket in the front centre console Example: vehicles with automatic transmission
X To open: slide cover :forwards until it
engages.
X Lift up the cover of socket ;.
X To close: briefly press cover :at the front.
The cover retracts. 280
FeaturesStowing and fea
tures

Engine compartment
Bonnet
Important safety notes G
WARNING
An unlocked bonnet may open up when the
vehicle is in motion and block your view. There is a risk of an accident.
Never unlock the bonnet when driving. Before
every trip, ensure that the bonnet is locked. G
WARNING
When being opened and closed, the bonnet
may suddenly fall into the closed position.
There is a risk of injury to persons in the range of movement of the bonnet.
Open and close the bonnet only when nobody
is in the range of movement. G
WARNING
If you open the bonnet while the engine is
overheating or while there is a fire in the
engine compartment, you could come into
contact with hot gases or other leaking ser-
vice products. There is a danger of injury.
Allow an overheating engine to cool down
before opening the bonnet. If there is a fire in the engine compartment, leave the bonnet
closed and notify the fire brigade. G
WARNING
There are moving components in the engine
compartment. Certain components may con-
tinue to move or suddenly move again even
after the ignition has been switched off, e.g.
the radiator fan. There is a risk of injury.
If you have to carry out work in the engine
compartment:
R switch off the ignition
R never touch the dangerous areas surround-
ing moving components, e.g. the rotation
area of the fan R
remove jewellery and watches
R keep items of clothing and hair, for exam-
ple, away from moving parts. G
WARNING
The ignition system and the fuel injection sys- tem operate with a high voltage. If you touch
the live components, you could receive an
electric shock. There is a danger of injury.
Never touch components of the ignition sys-
tem or the fuel injection system when the
ignition is switched on.
Active bonnet (pedestrian protection) Operating principle
! An active bonnet that had been triggered
must be repaired at a qualified specialist
workshop. The active bonnet function will
then be available again. The additional pedes- trian protection provided by the active bonnet will then be restored.
! Do not try to press down the raised bonnet
at the back. Otherwise, the bonnet could be
damaged.
i The active bonnet is only available in certain
countries.
The active bonnet can reduce the risk of injury to pedestrians in certain accident situations. Rais-
ing the active bonnet increases the clearance to hard components, such as the engine. If active bonnet
:has been triggered, it will be
raised at the back by approximately 50 mm.
Lids ;will then no longer rest on housings =.
The active bonnet is triggered by pyrotechnics.
You can reset a triggered active bonnet yourself. Engine compartment
289Maintenance and care Z

!
When DISTRONIC PLUS or the HOLD func-
tion is activated, the vehicle brakes automat- ically in certain situations.
To avoid damage to the vehicle, deactivate
DISTRONIC PLUS and the HOLD function in
the following or similar situations:
R when towing away
R in a car wash
! Preferably use car washes with adjustable
high-pressure jets for pre-washing. This cor-
responds with the specifications for cabriolet
programmes. In car washes that use high
water pressures, there is a risk that a small
amount of water may leak into the vehicle.
! Make sure that the vehicle is not subse-
quently treated with hot wax.
! Make sure that:
R the side windows and sliding sunroof or
soft top are closed completely.
R the blower for the ventilation/heating is
switched off (OFF button is depressed).
R the windscreen wiper switch is at position
0.
The vehicle could otherwise be damaged.
! In car washes with a towing mechanism,
make sure that the automatic transmission is
in transmission position N; otherwise, the
vehicle could be damaged.
R Vehicles with DIRECT SELECT lever and
key:
do not remove the key from the ignition
lock. Do not open the driver's door or front- passenger door when the engine is
switched off. Otherwise, the automatic
transmission selects park position Pauto-
matically and locks the wheels. You can
prevent this by shifting the automatic trans-
mission to Nbeforehand.
R Vehicles with DIRECT SELECT lever and
KEYLESS-GO:
do not open the driver's door or front-
passenger door when the engine is
switched off. Otherwise, the automatic
transmission selects park position Pauto-
matically and locks the wheels.
Observe the following to make sure that the
automatic transmission on vehicles with DIRECT
SELECT stays in position N:X
Make sure the vehicle is stationary and the
ignition is switched off.
X Turn the key to position 2in the ignition lock
(Y page 139).
Use the key instead of the Start/Stop button on vehicles with KEYLESS-GO.
X Depress the brake pedal and keep it
depressed.
X Shift the automatic transmission to position
N.
X Release the brake pedal.
X Release the parking brake.
X Switch off the ignition and leave the key in the
ignition lock.
You can wash the vehicle in an automatic car
wash from the very start.
Wash off excess dirt before cleaning the vehicle
in an automatic car wash.
After using an automatic car wash, wipe off wax
from the windscreen and the wiper blades. This
will prevent smears and reduce wiping noises
caused by residue on the windscreen.
Washing by hand In some countries, washing by hand is only
allowed at specially equipped washing bays.
Observe the legal requirements for each indi-
vidual country.
X Do not use hot water and do not wash the
vehicle in direct sunlight.
X Use a soft sponge to clean.
X Use a mild cleaning agent, such as a car
shampoo approved by Mercedes-Benz.
X Thoroughly hose down the vehicle with a gen-
tle jet of water.
X Do not point the water jet directly towards the
air inlet.
X Use plenty of water and rinse out the sponge
frequently.
X Rinse the vehicle with clean water and dry
thoroughly with a chamois.
X Do not let the cleaning agent dry on the paint-
work.
When using the vehicle in winter, remove all
traces of road salt deposits carefully and as
soon as possible. 296
CareMaintenance and care

Do not use a rapid charging device to start the vehicle. If your vehicle's battery is discharged, the
engine can be jump-started from another vehicle or from a second battery using jump leads.
Observe the following points:
R The battery is not accessible in all vehicles. If the other vehicle's battery is not accessible, jump-
start the vehicle using a second battery or a jump-starting device.
R Vehicles with a petrol engine: only jump-start the vehicle when the engine and exhaust system
are cold.
R Jump-starting may only be performed using batteries with a nominal voltage of 12 V.
R Only use jump leads that have a sufficient cross-section and insulated terminal clamps.
R If the battery is fully discharged, leave the battery that is being used to jump-start connected for
a few minutes before attempting to start. This charges the empty battery a little.
R Make sure that the two vehicles do not touch.
Make sure that:
R The jump leads are not damaged.
R Non-insulated parts of the terminal clamps do not come into contact with other metal parts while
the jump leads are connected to the battery.
R The jump leads cannot come into contact with parts which can move when the engine is running,
such as the V-belt pulley or the fan.
X Firmly depress the parking brake.
X Manual transmission: depress the clutch pedal fully and shift to neutral.
X Automatic transmission: shift the transmission to position P.
X Make sure the ignition is switched off. All indicator lamps in the instrument cluster must be off.
When using the key, turn the key to position 0in the ignition lock and remove it (Y page 139).
X Switch off all electrical consumers, e.g. rear window heating, lighting etc.
X Open the bonnet. Position number
Bidentifies the charged battery of the other vehicle or an equivalent jump-starting
device. 314
Jump-startingBreakdown assistance

You must avoid fire, naked flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the auxiliary heating before refuelling. G
WARNING
Fuels are poisonous and hazardous to health. There is a danger of injury.
Do not swallow fuel or let it come into contact
with skin, eyes or clothing. Do not inhale fuel
vapours. Keep fuels out of the reach of chil-
dren.
If you or others come into contact with fuel,
observe the following:
R Wash the fuel off any affected areas of skin
with water and soap immediately.
R If you get fuel in your eyes, rinse them thor-
oughly with clean water immediately. Seek immediate medical attention.
R If fuel is swallowed, seek immediate medi-
cal attention. Do not induce vomiting.
R Change any clothing that has come into
contact with fuel immediately.
Tank capacity Model Total capa-
city All models
66.0 l
Model Of which
reserve fuel All models
Approx. 8.0 l
Petrol
Fuel grade
!
Do not use diesel to refuel vehicles with a
petrol engine. Do not switch on the ignition if
you accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel system. Even small amounts of the wrong fuel can
result in damage to the fuel system and the
engine. Notify a qualified specialist workshop
and have the fuel tank and fuel lines drained
completely. !
Only refuel using unleaded petrol with at
least 95 ROZ, that conforms to the European standard EN 228 or E DIN or an equivalent
specification.
Fuel of this specification may contain up to
10% ethanol. Your vehicle is suitable for use
with E10 fuel. You may refuel your vehicle
using E10 fuel.
Fuel that does not conform to EN 228 can lead
to increased wear as well as damage to the
engine and exhaust system.
! Only use the fuel recommended. Operating
the vehicle with other fuels can lead to engine
failure.
! Do not use the following:
R E85 (petrol with 85% ethanol)
R E100 (100% ethanol)
R M15 (petrol with 15% methanol)
R M30 (petrol with 30% methanol)
R M85 (petrol with 85% methanol)
R M100 (100% methanol)
R petrol with additives containing metal
R diesel
Do not mix such fuels with the fuel recom-
mended for your vehicle.
Usually you will find information about the fuel
grade on the pump. If you cannot find the label
on the petrol pump, ask the filling station staff.
E 250: as a temporary measure, if the recom-
mended fuel is not available, you may also use
regular unleaded petrol with an octane rating of 93 RON.
All other models: as a temporary measure, if
the recommended fuel is not available, you may
also use regular unleaded petrol with an octane rating of 91 RON. This may reduce engine per-
formance and increase fuel consumption. Avoiddriving at full throttle and sudden acceleration.
Never refuel using fuel with a lower RON.
i In some countries, the available petrol may
not be sufficiently low in sulphur. This fuel can temporarily produce unpleasant odours,
especially on short journeys. As soon as sul-
phur-free fuel (sulphur content < 10 ppm) is
used for refuelling, the odours are reduced.
Information on refuelling (Y page 155).338
Service products and capacitiesTechnical data

E 200, E 250, E 400 (only for certain coun-
tries)
! Only refuel using sulphur-free unleaded pet-
rol with at least 95 ROZ, that conforms to the
European standard EN 228 or E DIN or an
equivalent specification.
You could otherwise impair engine output or
damage the emission control system.
i In some countries, the available petrol may
not be sufficiently low in sulphur. This fuel can temporarily produce unpleasant odours,
especially on short journeys. As soon as sul-
phur-free fuel (sulphur content < 10 ppm) is
used for refuelling, the odours are reduced.
Additives ! Operating the engine with fuel additives
added later can lead to engine failure. Do not mix fuel additives with fuel. This does not
include additives for the removal and preven-
tion of residue build-up. Petrol must only be
mixed with additives recommended by
Mercedes-Benz. Observe the instructions for
use in the product description. More informa- tion about recommended additives can be
obtained from any Mercedes-Benz Service
Centre.
Mercedes-Benz recommends that you use fuel
brands that have additives.
The quality of the fuel available in some coun-
tries may not be sufficient. Residue could build
up in the injection system as a result. In this
case, in consultation with a Mercedes-Benz Ser- vice Centre, the petrol may be mixed with the
cleaning additive recommended by Mercedes-
Benz. Always observe the notes and mixing
ratios specified on the container.
Diesel Fuel grade
G
WARNING
If you mix diesel fuel with petrol, the flash
point of this fuel mixture is lower than that of pure diesel fuel. When the engine is running,
components in the exhaust system may over-
heat unnoticed. There is a risk of fire.
Never refuel with petrol. Never add petrol to
diesel fuel. !
When refuelling, only use diesel fuel that
conforms to the European standard EN 590 or is of equivalent quality. Fuel that does not
conform to EN 590 can lead to increased wear
as well as damage to the engine and exhaust system.
! Do not use the following:
R marine diesel
R heating oil
R bio-diesel
R vegetable oil
R petrol
R paraffin
R kerosene
Do not mix such fuels with diesel fuel and do
not use any special additives. Otherwise,
engine damage may occur.
! Vehicles with diesel particle filters:
in
countries outside the EU, only use low sulphur
Euro diesel with a sulphur content of under
50 ppm. Otherwise, the emission control sys- tem could be damaged.
! Vehicles without a diesel particle filter:
in countries where only diesel fuel with a high sulphur content is available, you will need to
carry out your vehicle's oil change at shorter
intervals. More information about the interval for oil change can be obtained from any quali-
fied specialist workshop.
Usually you will find information about the fuel
grade on the pump. If you cannot find the label
on the petrol pump, ask the filling station staff.
Information on refuelling (Y page 155).
Low outside temperatures In winter months, diesel fuel with an improved
cold flow quality is available. In Europe, the
EN 590 standard defines various climate-
dependent temperature categories. Malfunc-
tions can be avoided by refuelling with diesel
fuel that corresponds to the climatic specifica-
tions outlined in EN 590. At unusually low out-
side temperatures, it is possible that the flow
characteristics of the diesel fuel could be insuf- ficient. Accordingly, diesel fuel from warmer
areas may not be suitable for operation in colder
climatic conditions.
i Further information on country-specific fuel
properties and fuel types with low-tempera- Service products and capacities
339Technical data Z

ture resistance can be obtained from oil com-
panies, e.g. at filling stations. AdBlue
®
Important safety notes Comply with the important safety notes for ser-
vice products when handling AdBlue ®
(Y page 337).
AdBlue ®
is a water-soluble fluid for the exhaust
gas aftertreatment of diesel engines. It is:
R non-toxic
R colourless and odourless
R non-flammable
If you open the AdBlue ®
tank, small amounts of
ammonia vapour may be released.
Ammonia vapours have a pungent odour and are
particularly irritating to the skin, to mucous
membranes and to the eyes. You may experi-
ence a burning sensation in your eyes, nose and throat. You may also experience coughing and
watery eyes.
Do not inhale any ammonia vapours that may be
released. Only fill the AdBlue ®
tank in well-ven-
tilated areas.
Low outside temperatures AdBlue
®
freezes at a temperature of approx-
imately -11 †. The vehicle is delivered from the
factory equipped with an AdBlue ®
preheating
system. Winter operation can thus be guaran-
teed even at temperatures below -11 †.
Additives !
Only use AdBlue ®
in accordance with ISO
22241. Do not use additives with AdBlue ®
and do not dilute AdBlue ®
with water. This
may destroy the BlueTEC exhaust gas after-
treatment system.
Purity !
Impurities in AdBlue ®
(e.g. due to other ser-
vice products, cleaning agents or dust) lead
to:
R increased emission values
R damage to the catalytic converter R
engine damage
R malfunctions in the BlueTEC ®
exhaust gas
aftertreatment system
Assuring the purity of AdBlue ®
is particularly
important with respect to avoiding malfunctions in the BlueTEC exhaust gas aftertreatment sys-
tem.
If AdBlue ®
is pumped out of the AdBlue ®
tank,
e.g. during repair work, do not use this fluid to
refill the tank. The purity of the fluid can no lon-
ger be guaranteed.
Capacities Model Total capacity
All models
25.0 l
Engine oil
General notes When handling engine oil, observe the important
safety notes on service products (Y page 337).
The quality of the engine oil is decisive for the
function and service life of an engine. After
extensive tests, Mercedes-Benz approves
engine oils that correspond to the current tech-
nical standard.
Therefore, only Mercedes-Benz approved
engine oils may be used in Mercedes-Benz
engines.
Further information on tested and approved
engine oils can be obtained from any Mercedes-
Benz Service Centre. Mercedes-Benz recom-
mends that you have the oil change carried out
at a qualified specialist workshop. Mercedes-
Benz approval is indicated on the oil container
by the inscription "MB-Freigabe" or "MB- 340
Service products and capacitiesTechnical data