warning lights MERCEDES-BENZ S-Class 2012 W221 Owner's Guide

Windshield wipers
Switching the windshield wipers on/
off
GWARNING
Wiper blades are components that are subject
to wear and tear. Replace the wiper blades
twice a year, preferably in the spring and fall.
Otherwise the windshield will not be wiped
properly. As a result, you may not be able to
observe surrounding traffic conditions and
could cause an accident.
! Do not operate the windshield wipers
when the windshield is dry, as this could
damage the wiper blades. Moreover, dust
that has collected on the windshield can
scratch the glass if wiping takes place when
the windshield is dry.
! If the windshield wipers leave smears on
the windshield after the vehicle has been
washed in an automatic car wash, wax or
other residues may be the reason for this.
Clean the windshield using washer fluid
after washing the vehicle in an automatic
car wash.
Combination switch
1$ Windshield wipers off2Ä Intermittent wipe, low 143Å
Intermittent wipe, high 154°
Continuous wipe, slow5¯ Continuous wipe, fastBí Single wipe/ î To wipe the
windshield using washer fluidXSwitch on the ignition.XTurn the combination switch to the
corresponding position.
! Intermittent wiping with rain sensor: due
to optical influences and the windshield
becoming dirty in dry weather conditions,
the windshield wipers may be activated
inadvertently. This could then damage the
windshield wiper blades or scratch the
windshield.
For this reason, you should always switch
off the windshield wipers in dry weather.
In the Ä or Å position, the appropriate
wiping frequency is set automatically
according to the intensity of the rain. In
the Å position, the rain sensor is more
sensitive than in the Ä position, causing
the windshield wipers to wipe more
frequently.
Replacing the wiper blades
Important safety notes
GWARNING
For safety reasons, switch off the windshield
wipers and remove the key from the ignition
lock before changing the wiper blades
(vehicles with KEYLESS-GO: make sure that
the on-board electronics are in state 0).
Otherwise, the wiper motor could be switched
on suddenly and cause injury.
! To avoid damaging the wiper blades,
make sure that you touch only the wiper
arm of the wiper.
! Never open the hood if a windshield wiper
arm has been folded away from the
windshield.
14 Rain sensor set to low sensitivity.
15 Rain sensor set to high sensitivity.Windshield wipers285Lights and windshield wipersZ

Notes on using climate control
Below, you can find a number of notes and
recommendations to help you use climate
control optimally.
R Activate climate control using the Ã
rocker switch. The indicator lamp in the
à rocker switch lights up.
R Set the temperature to 72 ‡ (22 †).
R Only use the "defrosting" function briefly
until the windshield is clear again.
R Only use "air-recirculation" mode briefly,
e.g. if there are unpleasant outside odors
or when in a tunnel. The windows could
otherwise fog up as, in air-recirculation
mode, no fresh air is drawn into the vehicle.
R Use the residual heat function if you want
to heat or ventilate the vehicle interior
when the ignition is switched off. The
"residual heat" function can only be
activated or deactivated with the ignition
switched off.
Operating the climate control system
Activating/deactivating climate
control
Important information
GWARNING
When the climate control system is
deactivated, the outside air supply and
circulation are also deactivated. Only choose
this setting for a short time. Otherwise the
windows could fog up, impairing visibility and
endangering you and others.
i Switch on climate control primarily using
the à rocker switch ( Y page 293).
Switching the front climate control on/
off using the front control panelXTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the ^ rocker switch
up or down.
The indicator lamp in the rocker switch
goes out. The previously selected settings
come into effect again.XTo deactivate: press the ^ rocker
switch up or down.
The indicator lamp in the rocker switch
lights up.
Switching the rear-compartment
climate control on/off using the front
control panel
XTurn the SmartKey to position 2 in the
ignition lock.XActivate the Y rear compartment
function via COMAND ( Y page 268).
The rear-compartment climate control can
be controlled via the front control panel
using the Y rear compartment function.XTo activate: press the ^ rocker switch
up or down.
The indicator lamp in the rocker switch
goes out. The previously selected settings
come into effect again.XTo deactivate: press the ^ rocker
switch up or down.
The indicator lamp in the rocker switch
lights up.292Operating the climate control systemClimate control

Switching the rear-compartment
climate control on/off using the rear
control panelXTurn the SmartKey to position 2 in the
ignition lock.XTo switch on: press rocker switch
K (Y page 291) up or down and select
AUTO .
or
XPress rocker switch K(Y page 291) up or
down and select MAN.XTo switch off: press rocker switch
K (Y page 291) up or down and select
OFF .
Activating/deactivating cooling with
the air dehumidification function
Important information
The cooling with air dehumidification function
is only available when the engine is running.
The air inside the vehicle is cooled and
dehumidified according to the temperature
selected.
GWARNING
If you switch off the cooling function, the
vehicle will not be cooled when weather
conditions are warm. The windows can fog up
more quickly. Window fogging may impair
visibility and endanger you and others.
Condensation may drip from the underside of
the vehicle when it is in cooling mode. This is
normal and not a sign that there is a
malfunction.
You can activate or deactivate the cooling
with air dehumidification function via
COMAND ( Y page 267).
i The cooling with air dehumidification
function uses refrigerant R134a. This
coolant does not contain
chlorofluorocarbons, and therefore does
not damage the ozone layer.
Problems with the cooling with air
dehumidification function
If you can no longer switch on the cooling with
air dehumidification function via COMAND,
the cooling with air dehumidification function
is switched off due to a malfunction.
XConsult a qualified specialist workshop.
Setting climate control to automatic
GWARNING
If you switch off the cooling function, the
vehicle will not be cooled when weather
conditions are warm. The windows can fog up
more quickly. Window fogging may impair
visibility and endanger you and others.
In automatic mode, the set temperature is
maintained automatically at a constant level.
The system automatically regulates the
temperature of the dispensed air, the airflow
and the air distribution.
Automatic mode will achieve optimal
operation if cooling with air dehumidification
is also activated. If desired, cooling with air
dehumidification can be deactivated.
Controlling the front climate control
using the front control panel
XTurn the SmartKey to position 2 in the
ignition lock.XSet the desired temperature.X To switch on: press the à rocker
switch up or down.
The indicator lamp in the à rocker
switch lights up.Operating the climate control system293Climate controlZ

Windows fogged up on the outsideXSwitch on the windshield wipers.XActivate automatic climate control.
iYou should only select this setting until
the windshield is clear again.
Rear window defroster
Activating/deactivating
GWARNING
Any accumulation of snow and ice should be
removed from the rear window before driving.
Visibility could otherwise be impaired,
endangering you and others.
The rear window defroster has a high current
draw. You should therefore switch it off as
soon as the window is clear as it only switches
off automatically after several minutes.
If the battery voltage is too low, the rear
window defroster may switch off.
XTurn the SmartKey to position 2 in the
ignition lock.XPress the ¤ rocker switch up or down.
The indicator lamp in the ¤ rocker
switch lights up or goes out.
Problems with the rear window
defroster
The rear window defroster has deactivated
itself prematurely or cannot be activated.
XSwitch off any consumers that are not
required, e.g. reading lamps or interior
lighting.
When the battery is sufficiently charged,
the rear window defroster is activated
again automatically.
Activating/deactivating air-
recirculation mode
You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle
from outside. The air already inside the
vehicle will then be recirculated.GWARNING
Fogged windows impair visibility,
endangering you and others. If the windows
begin to fog on the inside, switching off the
air recirculation mode immediately should
clear interior window fogging. If interior
window fogging persists, make sure the air
conditioning is activated, or press the ¬
button.
XTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the g rocker switch
up or down.
The indicator lamp in the g rocker
switch lights up.
i Air-recirculation mode is activated
automatically at high outside
temperatures. The indicator lamp in the
g rocker switch is not lit when
automatic air-recirculation mode is
activated.
Outside air is added after about 30
minutes.
X To deactivate: press the g rocker
switch up or down.
The indicator lamp in the g rocker
switch goes out.
i Air-recirculation mode deactivates
automatically:
R after approximately five minutes if
outside temperatures are less than about
41 ‡ (5 †)
R after approximately five minutes if
cooling with air dehumidification is
deactivated
R after approximately 30 minutes if outside
temperatures are over about
41 ‡ (5 †)
Operating the climate control system297Climate controlZ

Activating/deactivating the residual
heat function
It is possible to make use of the residual heat
of the engine to continue heating the
stationary vehicle for up to 30 minutes after
the engine has been switched off. The heating
time depends on the temperature that has
been set.
i The blower will run at a low speed
regardless of the airflow setting.
i If you activate the residual heat function
at high temperatures, only the ventilation
will be activated. The blower runs at
medium speed.XTurn the SmartKey to position 0 in the
ignition lock or remove it.XTo activate: press the Ì rocker switch
up or down.
The indicator lamp in the Ì rocker
switch lights up.XTo deactivate: press the Ì rocker
switch up or down.
The indicator lamp in the Ì rocker
switch goes out.
i Residual heat is deactivated
automatically:
R after about 30 minutes
R when the ignition is switched on
R if the battery voltage drops
R if the coolant temperature is too low
Setting the air vents
Important safety notes
GWARNING
When operating the climate control, the air
that enters the passenger compartment
through the air vents can be very hot or very
cold (depending on the set temperature). This
could cause burns or frostbite to unprotected
skin in the immediate area of the air vents.
Always keep sufficient distance between
unprotected parts of the body and the air
vents. If necessary, use the air distribution
adjustment to direct the air to air vents in the
vehicle interior that are not in the immediate
area of unprotected skin.
In order to ensure the direct flow of fresh air
through the air vents into the vehicle interior,
please observe the following notes:
R keep the air intake grille on the hood free
of blockages, such as ice, snow or leaves
R never cover the air vents or air intake grille
in the vehicle interior.
i For virtually draft-free ventilation, adjust
the sliders of the air vents to the center
position.
Setting the center air vents
:Fixed center air vent;Center air vent, right=Center vent thumbwheel, right?Center vent thumbwheel, leftACenter air vent, leftXTo open/close: turn thumbwheels =
and ? up or down.298Setting the air ventsClimate control

iYou do not have to remove the Start/Stop
button from the ignition lock when you
leave the vehicle. However, you should
always take the SmartKey with you when
leaving the vehicle. The vehicle can be
started with the Start/Stop button and the
electrical equipment can be operated while
the SmartKey is in the vehicle.:Start/Stop button;Ignition lockXInsert Start/Stop button : into ignition
lock ;.
i
When you insert Start/Stop button :
into ignition lock ;, the system requires a
detection time of approximately two
seconds before you can use Start/Stop
button :.
Start/Stop button
=USA only?Canada onlyXPosition 0: if Start/Stop button : has not
yet been pressed, this corresponds to the
SmartKey being removed from the ignition.XPosition 1: press Start/Stop button :.
You can now activate the windshield
wipers, for example.
i If you then open the driver's door when in
this position, the power supply is
deactivated.
XPosition 2 (ignition): press Start/Stop
button : twice.
i
If you press Start/Stop button : once
when in this position and the driver's door
is open, the power supply is deactivated
again.
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. If an indicator lamp does not go out after
the engine is started or if it lights up while the
vehicle is in motion, see ( Y page 422).
Starting the engine
Important safety notes
GWARNING
Inhalation of exhaust gas is hazardous to your
health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible death.
Do not run the engine in confined areas (such
as a garage) which are not properly ventilated.
If you think that exhaust gas fumes are
entering the vehicle while driving, have the
cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one
window fully open at all times.
! Do not depress the accelerator pedal
when starting the engine.
i Vehicles with a gasoline engine: the
catalytic converter is preheated for up to
304DrivingDriving and parking

30 seconds after a cold start. The sound of
the engine may change during this time.
Automatic transmissionXShift the transmission to position P.
The transmission position display in the
multifunction display shows P.
i
You can also start the engine when the
transmission is in position N.
Starting procedure with the SmartKey
i To start the engine using the SmartKey
instead of KEYLESS-GO, pull the Start/
Stop button out of the ignition lock.
XTo start a gasoline engine: turn the
SmartKey to position 3 in the ignition lock
( Y page 303) and release it as soon as the
engine is running.XTo start a diesel engine: turn the
SmartKey to position 2 in the ignition lock
( Y page 303).
The % preglow indicator lamp in the
instrument cluster lights up.XWhen the % preglow indicator lamp
goes out, turn the SmartKey to position 3
( Y page 303) and release it as soon as the
engine is running.
i You can start the engine without preglow
if the engine is warm.
Using KEYLESS-GO to start the engine
GWARNING
As long as the SmartKey is in your vehicle, the
vehicle can be started. Therefore, never leave
children unattended in the vehicle, as they
could otherwise accidentally start the engine.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Do
not leave children unattended in the vehicle,
or with access to an unlocked vehicle. A
child's unsupervised access to a vehicle could
result in an accident and/or serious personal
injury.
i The Start/Stop button can be used to
start the vehicle manually without inserting
the SmartKey into the ignition lock. The
Start/Stop button must be inserted into
the ignition lock and the SmartKey must be
in the vehicle. This mode for starting the
engine operates independently of the ECO
start/stop automatic engine start function.XDepress the brake pedal and keep it
depressed.XTo start a gasoline engine: press the
Start/Stop button ( Y page 303) once.
The engine starts.XTo start a diesel engine: press the Start/
Stop button ( Y page 303) once.
Preglow is activated and the engine starts.
i If the engine is warm, the preglow time is
shortened.
Pulling away
Automatic transmission
GWARNING
It is dangerous to shift the automatic
transmission out of parking position P or
neutral position N if the engine speed is
higher than idle speed. If your foot is not firmly
on the brake pedal, the vehicle could
accelerate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and when
your right foot is firmly on the brake pedal.
i It is only possible to shift the transmission
from position P to the desired position if
you depress the brake pedal. Only then is
the parking lock released. If you do not
depress the brake pedal, you can move the
DIRECT SELECT lever but the parking lock
remains engaged.
XDepress the brake pedal and keep it
depressed.XShift the transmission to position D or R.Driving305Driving and parkingZ

GWARNING
Keep in mind that turning off the engine alone
only will shift the automatic transmission into
neutral position N automatically.
Always shift the automatic transmission into
park position P before turning off the engine.
Otherwise the vehicle could roll away which
could result in an accident and/or serious
personal injury.
i If you cannot turn off the engine as
described here, see "Engine emergency
stop" ( Y page 487).
Vehicles with automatic transmission
XApply the electric parking brake.XShift the transmission to position P.
Using the SmartKey
XTurn the SmartKey to position 0 in the
ignition lock and remove it.
The immobilizer is activated.
i If you turn off the engine with the
SmartKey and then remove it from the
ignition lock or open a front door, the
automatic transmission shifts to P
automatically.
Using KEYLESS-GO
XPress the Start/Stop button (Y page 303).
The engine stops and all the indicator
lamps in the instrument cluster go out.
i When the driver's door is closed, this
corresponds to SmartKey position 1. When
the driver's door is open, it corresponds to
SmartKey position 0 or "SmartKey
removed".
i If you use the Start/Stop button to switch
off the engine, the automatic transmission
shifts to N automatically. If you then open
the driver's or front-passenger door, the
automatic transmission shifts to P.
i In an emergency, the engine can be
turned off while the vehicle is in motion by
pressing and holding the Start/Stop button
for three seconds. This function operates
independently from the ECO start/stop
automatic engine switch-off function.
Electric parking brake
General information
GWARNING
When leaving the vehicle, always remove the
SmartKey from the starter switch, take it with
you, and lock the vehicle. Do not leave
children unattended in the vehicle, or with
access to an unlocked vehicle. Children could
release the parking brake and/or shift the
automatic transmission out of park position
P , either of which could result in an accident
and/or serious personal injury.
Applying/releasing manually
XTo apply: press handle :.
The red F (USA only) or ! (Canada
only) indicator lamp in the instrument
cluster lights up.
i The electric parking brake can also be
applied when the SmartKey is removed.
XTo release: switch on the ignition.XPull handle :.
The red F (USA only) or ! (Canada
only) indicator lamp in the instrument
cluster goes out.
i The electric parking brake cannot be
released unless the SmartKey is in position
324ParkingDriving and parking

1 in the ignition lock or if the ignition has
been switched on using the Start/Stop
button.
Engaging the electric parking brake
automatically
The electric parking brake is automatically
applied if HOLD or DISTRONIC PLUS brakes
the vehicle until it is stationary and at least
one of the following conditions is fulfilled:
R the engine is switched off.
R the driver's door is open and the seat belt
is not fastened.
R the hood is released.
R the trunk lid is opened while the automatic
transmission is in position R.
R the vehicle is stationary for a lengthy
period.
The red F (USA only) or ! (Canada
only) indicator lamp in the instrument cluster
lights up.
i In addition to the electric parking brake,
P may also be engaged automatically.
Releasing the electric parking brake
automatically
The electric parking brake is released
automatically when the following conditions
are simultaneously fulfilled:
R the engine is running.
R the automatic transmission is in position
D or R.
R the hood is closed.
R your seat belt is fastened.
R you depress the accelerator pedal.
If the automatic transmission is in position
R , the trunk lid must be closed.
If your seat belt is not fastened, the following
conditions must be fulfilled to automatically
release the electric parking brake:
R the driver's door is closed.
R you shift out of P or you have previously
driven faster than 3 km/h.
R you have shifted out of P or you have
previously driven faster than 2 mph
(3 km/h).
Emergency braking
The vehicle can also be braked during an
emergency using the electric parking brake.
XWhile driving, push handle : of the electric
parking brake ( Y page 324).
i
The vehicle is braked as long as you keep
the handle of the electric parking brake
pressed. The longer the electric parking
brake handle is depressed, the greater the
braking force.
During braking:
R a warning tone sounds.
R the Please Release Parking Brake
message appears.
R the red F (USA only) or ! (Canada
only) indicator lamp in the instrument
cluster lights up.
When the vehicle has been braked to a
standstill, the electric parking brake is
engaged.
Parking the vehicle for a long period
If you leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharge.
XConnect a trickle charger.
i You can obtain information about trickle
chargers from a qualified specialist
workshop, e.g. an authorized Mercedes-
Benz Center.
Parking325Driving and parkingZ

more firmly. Maintain a safe distance from
vehicles in front.
After driving on a wet road or having the
vehicle washed, brake firmly while paying
attention to the traffic conditions. This will
warm up the brake discs, thereby drying them
more quickly and protecting them against
corrosion.
Limited braking performance on salt
treated roadsGWARNING
The layer of salt on the brake discs and the
brake pads/linings may cause a delay in the
braking effect, resulting in a significantly
longer braking distance, which could lead to
an accident.
To avoid this danger, you should:
R occasionally brake carefully, without
putting other road users at risk, when you
are driving on salted roads. This helps to
remove any salt that may have started to
build up on the brake discs and the brake
pads/linings.
R maintain a greater distance to the vehicle
ahead and drive with particular care.
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are removed
from the brake discs.
Servicing the brakes
! If the red brake warning lamp lights up in
the instrument cluster and you hear a
warning tone while the engine is running,
the brake fluid level may be too low.
Observe additional warning messages in
the multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked
immediately. This work should be carried
out at an authorized Mercedes-Benz
Center.
All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop. This work
should be carried out at an authorized
Mercedes-Benz Center.
Have the brake pads replaced and the brake
fluid renewed at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center.GWARNING
If brake pads or brake fluid other than those
recommended are used, the braking
properties of the vehicle can be degraded to
an extent that safe braking is substantially
impaired. This could result in an accident.
! Vehicles with 4MATIC: function or
performance tests may only be carried out
on a 2-axle dynamometer. If you are
planning to have the vehicle tested on such
a dynamometer, contact an authorized
Mercedes-Benz Center to obtain further
information first. Otherwise, you could
damage the drive train or the brake system.
! Vehicles with 4MATIC: as the ESP®
system operates automatically, the engine
and the ignition must be switched off
(SmartKey in position 0 or 1 in the ignition
lock or Start/Stop button in position 0 or
1 ) when the electric parking brake is being
tested on a brake dynamometer.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
! Vehicles with 4MATIC: as the ESP®
system operates automatically, the engine
and the ignition system must be switched
off (SmartKey in position 0 or 1 in the
ignition lock or Start/Stop button in
position 0 or 1) when:
R testing the electric parking brake on a
brake dynamometer.
R you intend to have the vehicle towed with
one of the axles raised.
328Driving tipsDriving and parking