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Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 23).
Overview of climate control systems
Important safety notes
GWARNING
Severe conditions (e.g. strong air pollution)
may require replacement of the filter before
its scheduled replacement interval. A clogged
filter will reduce the air volume to the interior
and the windows could fog up, impairing
visibility and endangering you and others.
Have a blocked filter replaced at a Mercedes-
Benz Center as soon as possible.
GWARNING
Follow the recommended settings for heating
and cooling given on the following pages.
Otherwise, the windows could fog up,
impairing visibility and endangering you and
others.
Automatic climate control controls the
temperature and the humidity in the vehicle
interior and filters undesirable substances
from the air.
Automatic climate control is only operational
when the engine is running. Optimum
operation is only achieved if you drive with the
side windows and panorama roof with power
tilt/sliding panel closed.
i Ventilate the vehicle for a brief period
during warm weather, e.g. using the
convenience opening feature ( Y page 83).
This will speed up the cooling process and
the desired vehicle interior temperature
will be reached more quickly.
i The integrated filter can filter out most
particles of dust and completely filters out
pollen. A clogged filter reduces the amount
of air supplied to the vehicle interior. For
this reason, you should always observe the
interval for replacing the filter, which is
specified in the Service Booklet. As it
depends on environmental conditions, e.g.
heavy air pollution, the interval may be
shorter than stated in the Service Booklet.
i It is possible that the residual heat
function may be activated automatically an
hour after the SmartKey is removed. The
vehicle is then ventilated for 30 minutes to
dry the air-conditioning system.118Overview of climate control systemsClimate control
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an authorized Mercedes-Benz Center for
this purpose.
! To prevent ESP ®
from intervening, the
ignition must be switched off (SmartKey in
position 0 or 1) if:
R the parking brake is being tested on a
brake dynamometer.
R the vehicle is being towed with only one
axle raised (not permitted for vehicles
with 4MATIC).
The brake system could otherwise be
damaged.
Refueling
Important safety notes
GWARNING
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious
personal injury.
Never allow sparks, flames or smoking
materials near gasoline.
Turn off the engine before refueling.
Whenever you are around gasoline, avoid
inhaling fumes and any skin or clothing
contact.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging to your
health.
GWARNING
Overfilling of the fuel tank may create
pressure in the system which could cause a
gas discharge. This could cause the gasoline
to spray back out when removing the fuel
pump nozzle, which could cause personal
injury.
! Do not use diesel to refuel vehicles with a
gasoline engine. Even small amounts of the
wrong fuel result in damage to the fuel
system and engine.
! Do not switch on the ignition if you
accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel lines.
Notify a qualified specialist workshop and
have the fuel tank and fuel lines drained
completely.
Gasoline
Fuel grade
! You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
! Use a filter when refueling from a fuel can.
Otherwise, the fuel lines and/or injection
system could be blocked by particles from
the fuel can.
i Only refuel with premium-grade unleaded
gasoline with a specified minimum octane
number of 91 (average value of 96 RON/
86 MON).
You will usually find information about the
fuel grade on the pump. If you cannot find
the label on the pump, ask the staff for
assistance.
You can find more information under "Fuel"
( Y page 304), or by contacting an
authorized Mercedes-Benz Service Center
or visiting http://www.mbusa.com (USA
only).
Refueling
Fuel filler flap
The fuel filler flap is unlocked or locked
automatically when you open or close the
vehicle with the SmartKey or using KEYLESS-
GO.
The position of the fuel filler cap is displayed
in the instrument cluster 8. The arrow
Refueling141Driving and parkingZ
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! Never use engine oil or an oil filter of a
specification other than is necessary to
fulfill the prescribed service intervals. Do
not change the engine oil or oil filter in
order to achieve longer replacement
intervals than those prescribed. You could
otherwise cause engine damage or damage
to the exhaust gas aftertreatment.
Follow the instructions in the service
interval display regarding the oil change.
Otherwise, you may damage the engine and
the exhaust gas aftertreatment.
The table shows which engine oils have been
approved for your vehicle.ModelEngine
modelMB
ApprovalGLK 350 36
GLK 350 4MATIC272229.5
i MB approval is indicated on the oil
containers.
Additives
! Do not use any additives in the engine oil.
This could damage the engine.
Engine oil viscosity
Viscosity describes the flow characteristics
of a fluid. If an engine oil has a high viscosity,
this means that it is thick; a low viscosity
means that it is thin.
Select an engine oil with an SAE (viscosity)
classification suitable for the prevailing
outside temperatures. The following table
shows the correct SAE classification to be
used. The low-temperature characteristics of
engine oils can deteriorate significantly, e.g.
as a result of aging, soot and fuel deposits. It
is therefore strongly recommended that you
carry out regular oil changes using an
approved engine oil with the appropriate SAE
classification.
Refrigerant of the air-conditioning
system
The air-conditioning system is filled with
R134a refrigerant and a special PAG
lubricant.
! Never use refrigerant R 12 (CFC) or
mineral lubricants. Otherwise, you could
damage the air-conditioning system.
Brake fluid
GWARNING
Over a period of time, the brake fluid absorbs
moisture from the air; this lowers its boiling
point.
If the boiling point of the brake fluid is too low,
vapor pockets may form in the brake system
when the brakes are applied hard (e.g. when
driving downhill). This would impair braking
efficiency.
You should have the brake fluid renewed at
regular intervals. The brake fluid change
intervals can be found in the Service Booklet.
Only use brake fluid approved by Mercedes-
Benz. Information about approved brake
fluids can be obtained from any authorized
Mercedes-Benz Center or on the Internet at
http://bevo.mercedes-benz.com.
36 USA only.306Service products and capacitiesTechnical data