fuel pump MERCEDES-BENZ S-CLASS SEDAN 2012 Owners Manual

pump nozzle, which could cause personal
injury.GWARNING
Hybrid vehicles: be sure to read the "HYBRID"
supplement. Otherwise, you could fail to
recognize dangers.
GWARNING
Do not fill diesel tanks with gasoline. Do not
mix diesel fuel with gasoline. Otherwise the
fuel system and engine could be damaged. In
addition, the vehicle could catch fire.
! Do not use gasoline to refuel vehicles with
a diesel engine. Do not use diesel to refuel
vehicles with a gasoline engine. Even a
small quantity of the wrong fuel will
damage 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.
! Overfilling the fuel tank could damage the
fuel system.
! Take care not to spill any fuel on painted
surfaces. You could otherwise damage the
paintwork.
! 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.
Further information on fuel and on fuel grades
can be found in the "Fuel" section
( Y page 525).
Refueling
Fuel filler flap:To open the fuel filler flap;To insert the fuel filler cap=Tire pressure table?Fuel type
The fuel filler flap is unlocked or locked
automatically when you open or close the
vehicle with the SmartKey or with KEYLESS-
GO.
The position of the fuel filler cap 8 is
displayed in the instrument cluster. The arrow
next to the filling pump indicates the side of
the vehicle.
Opening
XSwitch off the engine.XRemove the SmartKey from the ignition
lock.XKEYLESS-GO: open the driver’s door.
This corresponds to SmartKey position 0:
"SmartKey removed".
The driver’s door can be closed again.XPress the fuel filler flap in the direction of
arrow :.
The fuel filler flap opens slightly.XOpen the fuel filler flap fully.XTurn the fuel filler flap counter-clockwise
and remove it.XInsert the fuel filler cap into the holder
bracket on the inside of filler flap ;.322RefuelingDriving and parking

XCompletely insert the filler neck of the fuel
pump nozzle into the tank and refuel.XOnly fill the tank until the pump nozzle
switches off.
i Do not add any more fuel after the pump
stops filling for the first time. Otherwise,
fuel may leak out.
Closing
XReplace the cap on the filler neck and turn
clockwise until it engages audibly.XClose the fuel filler flap.
i If you drive with the fuel filler cap open,
the reserve fuel warning lamp flashes. In
addition, the ; Check Engine warning
lamp may light up. A message appears in
the multifunction display ( Y page 409).
For further information on warning and
indicator lamps in the instrument cluster,
see ( Y page 429).
i Close the fuel filler flap before locking the
vehicle. Otherwise, the locking pin of the
central locking prevents the fuel filler flap
from closing.
Refueling323Driving and parkingZ

with premium-grade unleaded gasoline
as soon as possible.
R do not drive at the maximum speed.
R avoid sudden acceleration.
R if the vehicle is carrying a light load, e.g.
two passengers without luggage, do not
allow the engine to rev above 3000 rpm.
R if the vehicle is fully loaded or is being
operated in mountainous terrain, do not
depress the accelerator pedal further
than Ô of the pedal travel.
Only refuel with premium-grade unleaded
gasoline with a minimum octane number of
91.
Reformulated Gasoline (RFG) and/or
unleaded gasoline with additives can be used.
However, the concentration of additives in
the fuel must be less than 10%, e.g.
R Ethanol
R TAME
R ETBE
R IPA
R TBA
For MTBE, the concentration should not
exceed 15%.
The concentration of methanol in gasoline
including other additives must not exceed
3%.
Using mixtures of methanol and ethanol is not
permitted. Gasohol, a mixture of 10% ethanol
and 90% unleaded gasoline, can be used.
All of these mix fuels must fulfill the fuel
requirements, e.g.:
R knock resistance
R boiling point
R vapor pressure
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.
i For further information, consult an
authorized Mercedes-Benz Center or visit
http://www.mbusa.com (USA only).Information on refueling ( Y page 321).
Additives
! Do not refuel with low-grade fuel and do
not use fuel additives that are not tested
and approved for Mercedes-Benz vehicles.
Damage to or malfunctions of the fuel
system may otherwise occur.
One of the main problems of poor fuel quality
is the forming of deposits that are created
during the gasoline combustion process.
Mercedes-Benz recommends that you use
branded fuels that have additives.
If you use fuels without these additives over
a longer period of time, carbon deposits may
build up. These deposits form at the inlet
valves and in the combustion chamber in
particular.
This could lead to engine problems, e.g.:
R longer engine warm-up phase
R uneven idle
R engine noise
R misfiring
R loss of power
Carbon deposits may form if the availability
of gasoline with relevant additives is
insufficient (in certain regions). In this case,
Mercedes-Benz recommends additives
approved for use in Mercedes-Benz vehicles;
see http://bevo.mercedes-benz.com.
For a list of approved products, consult an
authorized Mercedes-Benz Center. Comply
with the instructions for use on the product
label.
Do not mix other fuel additives with fuel. This
causes unnecessary costs and could damage
the engine.
Diesel
Fuel grade
GWARNING
Do not use gasoline to refuel vehicles with a
diesel engine. Never mix diesel with gasoline.
This causes damage to the fuel system and
526Service products and filling capacitiesTechnical data

engine and could result in the vehicle catching
fire.
! Only use commercially available vehicular
ULTRA-LOW SULFUR DIESEL FUEL (ULSD,
15 ppm maximum sulfur content) that
meets the ASTM D975 standard. If you do
not refuel with ULSD, you may damage the
BlueTEC exhaust gas aftertreatment
system of the vehicle.
! Do not use gasoline to refuel vehicles with
a diesel engine. Do not mix diesel fuel with
gasoline, kerosene or paraffin. This may
otherwise result in damage to the fuel
system and engine.
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.
i For further information, consult a
qualified specialist workshop or on the
Internet at http://www.mbusa.com (USA
only).
Information on refueling ( Y page 321).
Bio-diesel - FAME (fatty acid methyl ester)
Mercedes-Benz USA approves the use of bio-
diesel B5 for all BlueTEC diesel engines. The
concentration of bio-diesel in the ULSD may
not exceed 5 % by volume.
Pure biodiesel and diesel fuel with a higher
percentage of biodiesel, such as B20, can
damage the engine and the fuel system. For
this reason, they are not approved.
For more information, consult the gas station
staff. The bio-diesel B5 label on the gasoline
pump must clearly state that the standard for
ULSD has been fulfilled. If the label is not
clear, do not refuel the vehicle.
Do not refuel your vehicle with fuels unless
they have been approved by Mercedes-Benz.
Information on refueling ( Y page 321).Low outside temperatures
i Diesel fuel with improved cold flow
properties is available during the winter
months. Further information about fuel
properties can be obtained from oil
companies, e.g. at gas stations.
Flow improver
To improve the low-temperature resistance of
diesel fuel, a flow improver can be attached.
The effectiveness of a flow improver is not
guaranteed for every fuel.
Only use flow improvers tested and approved
by Mercedes-Benz. During use, please
observe the information on operation.
Correct dosage and sufficient mixing are
decisive in improving low-temperature
resistance with the flow improver.
Overdosage can potentially even decrease
low-temperature resistance and must
therefore be avoided. Follow the
manufacturer's guidelines on dosage.
Mix the additive into the diesel in good time,
before the flow characteristics of the diesel
become insufficient. Otherwise, malfunctions
can arise through heating the fuel system,
e.g. through parking in a heated garage.
More information about recommended flow
improvers can be obtained from any qualified
specialist workshop.
DEF
Please bear the following in mind
DEF is a non-flammable, non-toxic, colorless,
odorless and water-soluble fluid.
High outside temperatures
GWARNING
If you open the DEF tank cap, small amounts
of ammonia vapor may be released. This
depends in particular upon the age of the DEF.
Service products and filling capacities527Technical dataZ