air conditioning MERCEDES-BENZ S-Class 2012 W221 User Guide

Setting the side air ventsXTo open/close: turn thumbwheel = up or
down.
i Side window defroster vent : is never
completely shut, even if side air vent ; is
shut.
Setting the glove box air vent
When automatic climate control is activated,
the glove box can be ventilated, for instance
to cool its contents. The level of airflow
depends on the airflow and air distribution
settings.
! Close the air vent when heating the
vehicle.
At high outside temperatures, open the air
vent and activate the "cooling with air
dehumidification" function. Otherwise,
temperature-sensitive items stored in the
glove box could be damaged.
XTo open: turn thumbwheel : counter-
clockwise from position 3 to position 2.XTo close: turn thumbwheel : clockwise
from position 2 to position 3.
Setting the rear-compartment air
vents
Setting the center vents in the rear
compartment
:Rear-compartment air vent, left;Rear-compartment air vent, right=Rear-compartment air vent thumbwheel,
right?Rear control panel for automatic climate
controlARear-compartment air vent thumbwheel,
leftXTo open/close: turn thumbwheel = or
A to the right or left.
i
In vehicles without rear-compartment air-
conditioning system: close the rear-
compartment air vents when heating mode
is activated, as no warm air flows through
the rear vents in the basic heating setting.
Setting the air vents299Climate controlZ

or yellow. Always secure the vehicle against
rolling away before leaving it.
! Always switch the ignition off and take the
key with you when leaving the vehicle.
Automatic engine switch-off
The ECO start/stop function switches the
engine off automatically if the vehicle is
braked to a standstill and the brake remains
depressed with the transmission in position
D or N.
i You can still activate the HOLD function
when the vehicle is stationary, even if the
engine has been switched off
automatically. It is then not necessary to
continue applying the brakes during the
automatic stop phase. When you depress
the accelerator pedal, the engine starts
automatically and the braking effect of the
HOLD function is deactivated. Depress the
accelerator pedal carefully, as the engine
must be started first.
The engine is only switched off if:
R the outside temperature is within the range
which is suitable for the system.
R the engine is at normal operating
temperature.
R the set temperature for the vehicle interior
has been reached.
R the battery is sufficiently charged.
R the system detects that the windshield is
not fogged up when the air-conditioning
system is switched on.
R the hood is closed.
R no engine-relevant diagnostics are active.
R the driver's door is closed and the seat belt
is fastened.
Automatic engine start
The engine is started automatically if you:
R release the brake pedal when HOLD is not
activated and the transmission is in
position D or N
R shift the transmission to position R
R depress the accelerator pedal
R switch off the ECO start/stop function or
switch to drive program S or M
R unfasten your seat belt or open the driver's
door
The engine is also started automatically if:
R the vehicle starts to roll.
R the brake system requires this.
R the system detects moisture on the
windshield when the air-conditioning
system is switched on.
R the temperature in the vehicle interior
deviates from the set range.
R the charge level of the battery is too low.
Deactivating/activating the ECO start/
stop function
General information
You can deactivate and activate the ECO
start/stop function using COMAND
( Y page 261).
i You can also use the programmable
button ( Y page 120) to activate and
deactivate the ECO start/stop function if
you have assigned this function to the
button.
Deactivating
XDeactivate the ECO start/stop function
using COMAND ( Y page 261):
The ¤ ECO symbol goes out and the
Stop/Start deactivated display
message is shown in the multifunction
display.
i If drive program S or M has been selected,
the ECO start/stop function is always
deactivated.
Driving307Driving and parkingZ

XTo make brighter or dimmer: make sure
that Night View Assist Plus is activated.XTurn control : counter-clockwise or
clockwise.
Fogged up or dirty windshield
If the windshield in front of the camera is
fogged up or dirty on the inside or outside, the
Night View Assist Plus display is affected.
GWARNING
Please do not forget that your primary
responsibility is to drive the vehicle. A driver's
attention to the road must always be his/her
primary focus when driving. For your safety
and the safety of others, stop before trying to
remove window fogging or cleaning the
windshield in front of the Night View Assist
Plus camera.
Bear in mind that at a speed of just 30 mph
(approximately 50 km/h), your vehicle is
covering a distance of 44 feet
(approximately 14 m) every second.
XTo defrost: check the automatic air
conditioning settings (Y page 296) and fold
down the camera cover ( Y page 467).XTo defrost the inside of the windshield:
fold down the camera cover ( Y page 467)
and clean the windshield ( Y page 466).Driving systems359Driving and parkingZ

Display messagesPossible causes/consequences and M SolutionsÁ
Night View Assist
Currently
UnavailableThe temperature of the camera is too high.XWait until you see the Night View Assist Available
Again display message.
You can also:
XFold the camera cover down ( Y page 467).XAdjust the air distribution of the automatic air conditioning
upwards.Á
Night View Assist
Lights Must Be Set
to AUTO or ONA condition for activating Night View Assist Plus has not been
fulfilled.XTurn the light switch to c or L .Á
Night View Assist
Not In Reverse GearA condition for activating Night View Assist Plus has not been
fulfilled.XShift the transmission to P, N or D.Á
Night View Assist
Lights ON or AUTO,
Not in R GearA condition for activating Night View Assist Plus has not been
fulfilled.XTurn the light switch to c or L .XShift the transmission to P, N or D.Á
Night View Assist
Only When It Is
DarkYou have attempted to activate Night View Assist Plus in the
daytime.
Night View Assist Plus can only be activated when it is dark.¨
Vehicle RisingYour vehicle is adjusting to the level you have selected.¨
Vehicle Rising
Please Wait BrieflyThe vehicle level is too low when the vehicle is stationary. A
warning tone also sounds.XDo not pull away.
The vehicle level is set when the display message disappears.¨
STOP Car Too LowYou have pulled away while the vehicle level is still too low.
AIRMATIC sets the vehicle to the selected level after a short
period.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XApply the electric parking brake.XWait until the display message disappears before pulling away.Display messages409On-board computer and displaysZ

Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa is the
equivalent of 1 psi. Another unit for tire
pressure is bar. There are 100 kilopascals
(kPa) to 1 bar.
Load index
In addition to the load bearing index, the load
index may also be imprinted on the sidewall
of the tire. This specifies the load bearing
capacity more precisely.
Curb weight
The weight of a vehicle with standard
equipment including the maximum capacity
of fuel, oil and coolant. It also includes the air-
conditioning system and optional equipment
if these are installed in the vehicle, but does
not include passengers or luggage.
Maximum load rating
The maximum load rating in kilograms or
pounds is the maximum weight for which a
tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire.
Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axle
by two.
PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
This is pressure inside the tire applying an
outward force to each square inch of the tire's
surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold.
Tire pressure of cold tires
The tires are cold:
R if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
R if the vehicle has not been driven more than
1 mile (1.6 km).
Tread
The part of the tire that comes into contact
with the road.
Bead
The tire bead ensures that the tire sits
securely on the wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim.
Sidewall
The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
part and more than 2.3 kilograms (5 lbs).
512Definition of terms for tires and loadingWheels and tires

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
ApprovalS 550 36
S 550 4MATIC 36278229.5S 600275S 63 AMG157229.537S 65 AMG275S 350 BlueTEC
4MATIC642228.51,
229.31,
229.51
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
36 BlueEFFICIENCY
37 Restriction: only SAE 0W-40 or SAE 5W-40 engine oils may be used.528Service products and capacitiesTechnical data