
Auxiliary heating
Important safety notes G
DANGER
If the exhaust pipe is blocked or sufficient
ventilation is not possible, toxic exhaust
fumes can enter the vehicle, especially car-
bon monoxide. This is the case, e.g. in
enclosed spaces, or if the vehicle is stuck in
snow. There is a risk of fatal injuries.
You should switch off the auxiliary heating in
enclosed spaces which do not have an extrac- tion system, e.g. a garage. If the vehicle is
stuck in snow and you must leave the auxiliary
heating running, keep the exhaust pipe and
the area around the vehicle clear of snow. To guarantee a sufficient supply of fresh air, open
a window on the side of the vehicle away from the wind. G
WARNING
When the auxiliary heating is switched on,
parts of the vehicle can become very hot.
Flammable materials such as leaves, grass or twigs may ignite if they come into contact
with:
R hot parts of the exhaust system
R the exhaust gas itself
There is a risk of fire.
When the auxiliary heating is switched on,
make sure that:
R no flammable materials come into contact
with hot vehicle components
R the exhaust gas can escape from the
exhaust pipe unhindered
R the exhaust gas does not come into contact
with flammable materials.
The auxiliary heating is fitted under the front
wing on the left-hand side of the vehicle. The
emissions outlet is found behind the left front
wheel.
! Operating the auxiliary heating/ventilation
draws on the vehicle battery. After you have
heated or ventilated the vehicle a maximum of two times, drive for a longer distance. Switch the auxiliary heating on regularly once a
month for about ten minutes.
The auxiliary heating heats the air in the vehicle
interior to the set temperature. This occurs with- out using the heat of the running engine. The
auxiliary heating is operated directly using the
vehicle's fuel. For this reason, the tank content
must be at least at reserve fuel level to ensure
that the auxiliary heating functions.
The auxiliary heating or auxiliary ventilation
automatically adjusts to changes in tempera-
ture and weather conditions. For this reason,
the auxiliary heating could switch from ventila-
tion mode to heating mode or from heating
mode to ventilation mode.
The auxiliary heating switches off when the
engine is switched off. The auxiliary ventilation
switches off when you turn the key to position 2
(Y page 146).
The auxiliary heating switches off automatically after 50 minute s.This time limit can be altered.
To do this, visit a qualified specialist workshop.
You cannot use the auxiliary ventilation to cool
the vehicle interior to a temperature lower than
the outside temperature.
Before switching on X
Turn the key to position 2in the ignition lock
(Y page 146).
X Set the desired temperature.
The auxiliary heating/ventilation can be activa-
ted even when climate control is set to manual.
Optimum comfort can be attained when the sys-
tem is set to automatic mode. Set the temper-
ature to 22 †.
The auxiliary heating or auxiliary ventilation can
be switched on/off using the button on the
centre console or the remote control.
The on-board computer can be used to specify
up to three departure times, one of which may
be preselected (Y page 247).138
Operating the climate control systemClimate control 

Problems with the fuel and fuel tank
Problem
Possible causes/consequences and
M
MSolutions Fuel is leaking from the
vehicle.
G
WARNING
The fuel line or the fuel tank is faulty.
There is a risk of fire or explosion. X Apply the electric parking brake.
X Switch off the engine.
X Remove the key from the ignition lock.
or, on vehicles with KEYLESS-GO start function or KEYLESS ‑GO:
X Open the driver's door.
The on-board electronics now have status 0. This is the same as the
key having been removed.
X Do not restart the engine under any circumstances.
X Consult a qualified specialist workshop. The engine does not
start. The fuel tank of a vehicle with a diesel engine has been run completely
dry.
X Refuel the vehicle with at least 5 litres of diesel.
X Turn the ignition on for approximately ten seconds (Y page 146).
X Start the engine continuously for a maximum of ten seconds until it
runs smoothly.
If the engine does not start: X Turn the ignition on again for a maximum of ten seconds
(Y page 146).
X Start the engine again continuously for a maximum of ten seconds
until it runs smoothly.
If the engine does not start after three attempts:
X Consult a qualified specialist workshop. The fuel filler flap cannot
be opened. The fuel filler flap is not unlocked.
X Unlock the vehicle (Y page 79). The key battery is discharged or nearly discharged.
X Unlock the vehicle using the emergency key element (Y page 80).The fuel filler flap is unlocked, but the opening mechanism is jammed.
X Consult a qualified specialist workshop. AdBlue
®
(BlueTEC vehicles only)
General notes To function properly, BlueTEC exhaust gas after-
treatment must be operated with the reducing
agent AdBlue ®
. Topping up AdBlue ®
is part of
the maintenance work. Under normal operating conditions, a full tank of AdBlue
®
should last
until the next service due date.
When the supply of AdBlue ®
is down to approx-
imately 3.8 l, the Refill AdBlue See Own‐ Refill AdBlue See Own‐
er's Manual
er's Manual message is shown in the multi-
function display. 164
RefuellingDriving and parking 

X
Add at least 3.8 lof AdBlue ®
.
X Switch on the ignition for at least 60 seconds.
X Start the engine.
i You can also have the AdBlue ®
tank refilled
at a qualified specialist workshop.
Before driving your vehicle outside Europe, have
the AdBlue ®
supply checked at a qualified spe-
cialist workshop.
Further information about BlueTEC exhaust gas
aftertreatment and about AdBlue ®
can
be obtained from any Mercedes-Benz Service
Centre.
Important safety notes 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.
Do not swallow AdBlue ®
or let it come into con-
tact with skin, eyes or clothing. Keep AdBlue ®
away from children.
If you or others come into contact with AdBlue ®
,
observe the following:
R immediately rinse AdBlue ®
off your skin with
soap and water.
R if AdBlue ®
comes into contact with your eyes,
immediately rinse them thoroughly with clean water. Seek medical attention immediately.
R if AdBlue ®
is swallowed, immediately rinse
your mouth out thoroughly. Drink plenty of
water. Seek medical attention immediately.
R change immediately out of clothing that has
come into contact with AdBlue ®
.
! Only use AdBlue ®
in accordance with
ISO 22241. Do not mix any additives with AdBlue
®
, and do not dilute AdBlue ®
with
water. This may destroy the BlueTEC exhaust
gas aftertreatment system.
! In order to fill the AdBlue ®
tank, the vehicle
must be parked on a level surface. The
AdBlue ®
tank can only be filled as intended
with the vehicle parked on a level surface.
Fluctuations in capacity will thus be avoided.
Filling a vehicle standing on an uneven sur-
face is not permitted. There is a danger of
overfilling, which can cause damage to Blue-
TEC exhaust gas aftertreatment components.
! Surfaces which have come into contact with
AdBlue ®
while refilling should be rinsed
immediately with water, or remove AdBlue ®
with a moist cloth and cold water. If AdBlue ®
has already crystallised, use a sponge and
cold water to clean the area. AdBlue ®
residue
crystallises after a certain amount of time and soils the affected surfaces.
! AdBlue ®
is not a fuel additive and must not
be added to the fuel tank. If AdBlue ®
is added
to the fuel tank, this can lead to engine dam-
age.
Have the AdBlue ®
tank refilled at a qualified
specialist workshop. However, you can also top
up the AdBlue ®
tank:
R at a filling station with an AdBlue ®
filling pump
R with AdBlue ®
refill bottles
R with an AdBlue ®
refill canister
When the pump nozzle switches off automati-
cally during filling at a filling pump, the AdBlue ®
tank has been completely filled. Do not fill the
AdBlue ®
tank any further. AdBlue ®
may leak
out.
To avoid transporting already opened refill con-
tainers in the vehicle, completely empty refill
bottles or canisters when filling the AdBlue ®
tank, if possible.
Further information on AdBlue ®
(Y page 377). Refuelling
165Driving and parking Z 

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
31.8 l
Engine oil
General notes When handling engine oil, observe the important
safety notes on service products (Y page 374).
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-
Approval" and the corresponding designation,
e.g. MB-Freigabe or MB-Approval 229.51.
You can call up an overview of approved engine oils on the Internet at
http://bevo.mercedes-benz.com by entering
the designation, e.g. 229.5.
The table shows which engine oils have been
approved for your vehicle.
You can find the correct values for your model
with the help of the VIN on the vehicle identifi-
cation plate (Y page 373).378
Service products and capacitiesTechnical data