ignition MERCEDES-BENZ CLS 2012 Service Manual

iThe cooling with air dehumidification
function uses refrigerant R134a. This
coolant does not contain
chlorofluorocarbons, and therefore does
not damage the ozone layer.
Activating/deactivatingXTo activate: press the ¿ button.
The indicator lamp in the ¿ button lights
up.XTo switch off: press the ¿ button.
The indicator lamp in the ¿ button goes
out. The cooling with air dehumidification
function has a delayed switch-off feature.
Problems with the cooling with air
dehumidification function
When you press the ¿ button, the
indicator lamp in the button flashes three
times or remains off. You can no longer switch
on the cooling with air dehumidification
function.
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.
Adjusting the climate mode settings
(AIR FLOW)
This function is only available with automatic
climate control.
The climate control settings are especially
effective at high temperatures.
You can select the following climate control
settings in automatic mode:FOCUShigh airflow that is set slightly
coolerMEDIUMmedium airflow, standard settingDIFFUSElow airflow that is set slightly
warmer and with a lower rate of
airflowXTurn the SmartKey to position 2 in the
ignition lock.XPress the à button.XPress the ñ button repeatedly until the
desired climate mode appears in the
display.
Setting the temperature
Dual-zone automatic climate control
Different temperatures can be set for the
driver's and front-passenger sides.
XTurn the SmartKey to position 2 in the
ignition lock.XTo increase/reduce: turn controls : and
B clockwise or counter-clockwise
( Y page 119).
Only change the temperature setting in
small increments. Start at 72 ‡ (22 † ).Operating the climate control system123Climate controlZ

3-zone automatic climate control
Automatic climate control climate zones
You can select different temperature settings
for the driver's and front-passenger sides as
well as for the rear compartment.
XTurn the SmartKey to position 2 in the
ignition lock.XTo increase/reduce the temperature in
the front: turn controls : and B
clockwise or counter-clockwise
( Y page 121).
Only change the temperature setting in
small increments. Start at 72 ‡ (22 † ).XTo increase/reduce the temperature in
the rear compartment using the front
control panel: press the á button.
The indicator lamp in the á button goes
out.XTurn control : clockwise or counter-
clockwise ( Y page 121).
Only change the temperature setting in
small increments. Start at 72 ‡ (22 † ).
The temperature setting for the driver's
side is adopted for the rear compartment
and the front-passenger side.XTo increase/reduce the temperature in
the rear compartment using the rear
control panel: press the r or s
button on the rear control panel.
Only change the temperature setting in
small increments. Start at 72 ‡ (22 † ).i If you leave the vehicle parked for longer
than 30 minutes, the temperature setting
for the rear compartment then switches
back to 72 ‡.
Setting the air distribution
PDirects the airflow through the center
and side air ventsODirects the airflow through the
footwell air ventsSDirects the airflow through the center
and side air vents as well as the
footwell air vents¯Directs the airflow through the
defroster ventsbDirects the airflow through the
defroster, center and side air vents. 11aDirects the airflow through the
footwell and defroster vents_Directs the airflow through the
defroster, center and side air vents as
well as the footwell air vents 11
i
Regardless of the air distribution setting,
airflow is always directed through the side
air vents. The side air vents can only be
closed when the controls on the side air
vents are turned downwards.
XTurn the SmartKey to position 2 in the
ignition lock.XPress the _ button repeatedly until the
desired symbol appears in the display.
Setting the airflow
XTurn the SmartKey to position 2 in the
ignition lock.XTo increase: press the K button.XTo reduce: press the I button.11
Canada only.124Operating the climate control systemClimate control

iYou can use automatic climate control to
set the airflow in the rear compartment
separately.
Switching the ZONE function on/off
XTo switch on: press the á button.
The indicator lamp in the á button lights
up.
Dual-zone automatic climate control: the
temperature setting for the driver's side is
not adopted for the front-passenger side.
3-zone automatic climate control: the
temperature setting for the driver's side is
not adopted for the front-passenger side
and the rear compartment.
When the buttons or controls for
temperature, airflow or air distribution are
activated, the temperature setting for the
driver's side is not adopted for the other
climate control zones.
XTo switch off: press the á button.
The indicator lamp in the á button goes
out.
Dual-zone automatic climate control: the
temperature setting for the driver's side is
adopted for the front-passenger side.
3-zone automatic climate control: the
temperature setting for the driver's side is
adopted for the front-passenger side and
the rear compartment.
Defrosting the windshield
You can use this function to defrost the
windshield or to defrost the inside of the
windshield and the side windows.
i You should only select the defrosting
function until the windshield is clear again.
XTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the ¬ button.
The indicator lamp in the ¬ button lights
up.
The climate control system switches to the
following functions:
R cooling with air dehumidification on
R high airflow 12
R high temperature 12
R air distribution to the windshield and
front side windows
R air-recirculation mode offXTo switch off: press the ¬ button.
The indicator lamp in the ¬ button goes
out. The previously selected settings come
into effect again. The cooling with air
dehumidification function remains on. Air-
recirculation mode remains deactivated.
or
XPress the à button.
The indicator lamp in the ¬ button goes
out. Airflow and air distribution are set to
automatic mode.
or
XTurn controls : or B clockwise or
counter-clockwise ( Y page 119),
( Y page 121).
or
XPress the K or I button.
MAX COOL maximum cooling
The MAX COOL function is only available in
vehicles for the USA.
MAX COOL is only operational when the
engine is running.
12 Depending on the outside temperature.Operating the climate control system125Climate controlZ

When you activate MAX COOL, climate
control switches to the following functions:
R maximum cooling
R maximum airflow
R air-recirculation mode onXTo activate: press the Ù button.
The indicator lamp in the button lights up.XTo deactivate: press the Ù button
again.
The indicator lamp goes out. The previously
selected settings come into effect again.
Defrosting the windows
Windows fogged up on the inside
XActivate the ¿ cooling with air
dehumidification function.XActivate automatic mode Ã.XIf the windows continue to fog up, activate
the defrosting function ( Y page 125).
i
You should only select this setting until
the windshield is clear again.
Windows fogged up on the outside
XSwitch on the windshield wipers.XPress the _ button repeatedly until the
P or O symbol appears in the
display.
i You 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 ¤ button.
The indicator lamp in the ¤ button 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.
The operation of air-recirculation mode is the
same for all control panels.
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.
126Operating the climate control systemClimate control

XTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the g button.
The indicator lamp in the g button lights
up.
i In the event of high pollution levels 13
or at
high outside temperatures, air-
recirculation mode is automatically
activated. When air-recirculation mode is
activated automatically, the indicator lamp
in the g button is not lit.
Outside air is added after about 30
minutes.
XTo switch off: press the g button.
The indicator lamp in the g button 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 †)
Activating/deactivating the residual
heat function
The residual heat function is only available in
vehicles for Canada with automatic climate
control.
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 button.
The indicator lamp in the Ì button lights
up.XTo switch off: press the Ì button.
The indicator lamp in the Ì button 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.
13 Automatic climate control only.Setting the air vents127Climate controlZ

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 22).
Driving
Important safety notes
GWARNING
Make sure absolutely no objects are
obstructing the pedals' range of movement.
Keep the driver's footwell clear of all
obstacles. If there are any floormats or
carpets in the footwell, make sure the pedals
still have sufficient clearance.
During sudden driving or braking maneuvers
the objects could get caught between the
pedals. You could then no longer brake or
accelerate. This could lead to accidents and
injury.
GWARNING
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
control. Your vehicle's ABS will not prevent
this type of loss of control.
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.
! Warm up the engine quickly. Do not use
the engine's full performance until it has
reached operating temperature.
Only shift the automatic transmission to
the desired drive position when the vehicle
is stationary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery
roads. You could otherwise damage the
drive train.
! AMG vehicles: at low engine oil
temperatures (below 68 ‡ (+20 †), the
maximum engine speed is restricted in
order to protect the engine. To protect the
engine and maintain smooth engine
operation, avoid driving at full throttle when
the engine is cold.
SmartKey positions
SmartKey
gTo remove the SmartKey(shift the transmission to position P)1Power supply for some consumers, such
as the windshield wipers2Ignition (power supply for all consumers)
and drive position3To start the engine
If the SmartKey is in position 0 in the ignition
lock for an extended period of time, it can no
132DrivingDriving and parking

longer be turned in the ignition lock. The
steering is then locked. To unlock, remove the
SmartKey and reinsert it into the ignition lock.
The steering is locked when you remove the
SmartKey from the ignition lock.
i The SmartKey can be turned in the
ignition lock even if it is not the correct
SmartKey for the vehicle. The ignition is not
switched on. The engine cannot be started.
KEYLESS-GO
General information
Vehicles with KEYLESS-GO are equipped with
a SmartKey featuring an integrated KEYLESS-
GO function and a detachable Start/Stop
button.
The Start/Stop button must be inserted into
the ignition lock and the SmartKey must be in
the vehicle.
Pressing the Start/Stop button several times
in succession corresponds to the different
SmartKey positions in the ignition lock. This
is only the case if you are not depressing the
brake pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts
immediately.
The Start/Stop button can be removed from
the ignition lock. Then, you can insert the
SmartKey into the ignition lock.
i You 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.
Driving133Driving and parkingZ

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 243).
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 The catalytic converter is preheated for
up to 30 seconds after a cold start. During
this time, the engine sound may be
different.
i The catalytic converter is preheated for
up to 30 seconds after a cold start. During
this time, the engine sound may be
different.
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.
XTurn the SmartKey to position 3 in the
ignition lock (Y page 132) and release it as
soon as the engine is running.
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.XPress the Start/Stop button ( Y page 133)
once.
The engine starts.134DrivingDriving and parking

:ECO symbol;ECO start/stop display message
The ECO start/stop function is activated each
time the engine is switched on. If all the
requirements are fulfilled for automatic
engine switch-off ( Y page 136), green ECO
symbol : is shown in the multifunction
display and Stop/Start active ; appears.
If all the requirements are not fulfilled, ECO
symbol : is shown in yellow and Stop/
Start inactive ; appears.
If the ECO start/stop function is deactivated
( Y page 137), ECO symbol : is not shown.
GWARNING
If the engine is switched off and the ECO
symbol is shown in green in the multifunction
display, the engine has been switched off
automatically. All of the vehicle's systems
remain active. If you open the door, unfasten
your seat belt or remove your foot from the
brake pedal, the engine will automatically
start. The vehicle may begin moving. You
could suffer serious or even fatal injury or
cause an accident resulting in injury or death.
Never leave the vehicle while the ECO symbol
in the multifunction display is shown in green
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 front 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 by
pressing the ECO button
R switch to drive program S, 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.
136DrivingDriving and parking

Problems with the engineProblemPossible causes/consequences and M SolutionsThe engine does not
start. The starter motor
can be heard.R There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.XBefore attempting to start the engine again, turn the SmartKey
in the ignition back to position 0 or press the Start/Stop button
repeatedly until all indicator lamps in the instrument cluster go
out.XTry to start the engine again ( Y page 134). Avoid excessively
long and frequent attempts to start the engine as these will drain
the battery.
If the engine does not start after several attempts:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the battery is too weak
or discharged.XJump-start the vehicle ( Y page 305).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.The starter motor was exposed to a thermal load that was too high.XAllow the starter motor to cool down for approximately two
minutes.XTry to start the engine again.
If the engine still does not start:
XConsult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center.138DrivingDriving and parking