air condition MERCEDES-BENZ E-Class CABRIOLET 2012 C207 User Guide

Notes on using 3-zone automatic
climate control
The following contains instructions and
recommendations to enable you to get the
most out of your automatic climate control.
R Activate climate control using the à and
¿ buttons. The indicator lamps above
the à and ¿ buttons light up. You
can also set the airflow and air distribution
of the automatic climate control to one of
three levels (FOCUS/MEDIUM/DIFFUSE).
You can set the desired level using button
G . The MEDIUM level is recommended.
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 ZONE function to adopt the
temperature settings on the driver's side
for the front-passenger side and the rear
compartment as well. The indicator lamp
above the á button goes out.
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 button ( Y page 135).
Activating/deactivatingXTurn the SmartKey to position 2 in the
ignition lock.XTo switch on: press the à button.
The indicator lamp above the à button
lights up. Airflow and air distribution are set
to automatic mode.
or
XPress the ^ button.
The indicator lamp above the ^ button
goes out. The previously selected settings
come into effect again.XTo switch off: press the ^ button.
The indicator lamp above the ^ button
lights up.
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.
134Operating the climate control systemClimate control

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 above the ¿ button
lights up.XTo switch off: press the ¿ button.
The indicator lamp above 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.
XTurn the SmartKey to position 2 in the
ignition lock.XSet the desired temperature.XTo activate: press the à button.
The indicator lamp above the à button
lights up. Automatic air distribution and
airflow are activated.
i 3-zone automatic climate control: when
automatic mode is activated, you can
select a climate mode setting
( Y page 135).
XTo deactivate: press the air distribution
button.
Dual-zone automatic climate control: press
button F(Y page 131).
3-zone automatic climate control: press
button I(Y page 133).
The indicator lamp above the à button
goes out.
or
XPress the airflow button.
Dual-zone automatic climate control: press
button G(Y page 131).
3-zone automatic climate control: press
button H(Y page 133).
The indicator lamp above the à button
goes out.
Adjusting the climate mode settings
(AIR FLOW)
This function is only available with 3-zone
automatic climate control.
The climate mode settings are especially
effective at high temperatures.
You can select the following climate mode
settings in automatic mode:
FOCUShigh airflow that is set slightly
coolerMEDIUMmedium airflow, standard settingDIFFUSElow airflow that is set slightly
warmer and with less draftOperating the climate control system135Climate controlZ

XTurn the SmartKey to position 2 in the
ignition lock.XPress the ¤ button.
The indicator lamp above 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.
XTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the g button.
The indicator lamp above the g button
lights up.i In the event of high pollution levels 14
or at
high outside temperatures, air-
recirculation mode is automatically
activated. When air-recirculation mode is
activated automatically, the indicator lamp
above the g button does not light up.
Outside air is added after about 30
minutes.XTo switch off: press the g button.
The indicator lamp above 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.
Coupe: the residual heat function only works
optimally if the side windows and panorama
roof with power tilt/sliding panel are closed.
Cabriolet: the residual heat function only
works optimally if the soft top is closed.
i The blower will run at a low speed
regardless of the airflow setting.
14 Automatic climate control only.Operating the climate control system139Climate controlZ

iIf you activate the residual heat function
at high temperatures, only the ventilation
will be activated. The blower runs at
medium speed.
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.XTurn the SmartKey to position 0 in the
ignition lock or remove it.XTo activate: press the Ì button.
The indicator lamp above the Ì button
lights up.XTo switch off: press the Ì button.
The indicator lamp above 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.
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 inlet between the windshield
and 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
:Center air vent, left;Center air vent, right=Center vent thumbwheel, right?Center vent thumbwheel, leftXTo open/close: turn thumbwheels =
and ? up or down.
Setting the side air vents
140Setting the air ventsClimate control

Rolling with the engine switched offGWARNING
There is no power assistance for the steering
and the brake when the engine is not running.
Steering and braking requires significantly
more effort and you could lose control of the
vehicle and cause an accident as a result.
Do not turn off the engine while the vehicle is
in motion.
Exhaust check
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.
Certain engine systems are designed to keep
the level of poisonous components in exhaust
fumes within legal limits.
These systems only work at peak efficiency
when they are maintained exactly in
accordance with the manufacturer's
specifications. For this reason, all work on the
engine must be carried out only by qualified
and authorized Mercedes-Benz technicians.
The engine settings must not be changed in
any circumstances. Furthermore, all specific
service work must be carried out at regular
intervals and in accordance with the
Mercedes-Benz service requirements. Details
can be found in the Service Booklet.
Brakes
Important safety notesGWARNING
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
Make sure that you do not endanger other
road users when you apply the brakes.
Downhill gradients
! On long and steep gradients, you must
reduce the load on the brakes by shifting
early to a lower gear. This allows you to take
advantage of the engine braking effect and
helps avoid overheating and excessive
wear of the brakes.
When you take advantage of the engine
braking effect, a drive wheel may not turn
for some time, e.g. on a slippery road
surface. This could cause damage to the
drive train. This type of damage is not
covered by the Mercedes-Benz warranty.
Heavy and light loads
GWARNING
Depressing the brake pedal constantly results
in excessive and premature wear to the brake
pads.
It may also cause the brakes to overheat,
seriously impairing their effectiveness. It may
then not be possible to stop the vehicle in
sufficient time to avoid an accident.
If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately, but
drive on for a short while. This allows the
airflow to cool the brakes more quickly.
Driving tips161Driving and parkingZ

Wet roadsGWARNING
After driving in heavy rain for some time
without applying the brakes or through water
deep enough to wet brake components, the
first braking action may be somewhat
reduced. You have to depress the brake pedal
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 roads
GWARNING
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.
! 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 parking brake on a brake
dynamometer.
R you intend to have the vehicle towed with
one of the axles raised.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
If your brake system is subject only to
moderate loads, you should test the
functionality of your brakes at regular
intervals by pressing firmly on the brake pedal
at high speeds. This improves the grip of the
brake pads.
162Driving tipsDriving and parking

GWARNING
Make sure that you do not endanger other
road users when you apply the brakes.
You can find a description of Brake Assist
(BAS) on ( Y page 62) or of BAS PLUS on
( Y page 62).
Driving on wet roads
Hydroplaning
If water has accumulated to a certain depth
on the road surface, there is a danger of
hydroplaning occurring, even if:
R you drive at low speeds.
R the tires have adequate tread depth.
For this reason, in the event of heavy rain or
in conditions in which hydroplaning can occur
you must drive in the following manner:
R reduce your speed
R avoid ruts
R brake carefully
Driving on flooded roads
! Do not drive through flooded areas.
Check the depth of any water before driving
through it. Drive slowly through standing
water. Otherwise, water may enter the
vehicle interior or the engine compartment.
This can damage the electronic
components in the engine or the automatic
transmission. Water can also be drawn in
by the engine's air suction nozzles and this
can cause engine damage.
Winter driving
General notes
GWARNING
If the vehicle becomes trapped in snow,
ensure that snow is kept away from the
exhaust pipe and from around the vehicle as
long as the engine is running. Otherwise,
poisonous carbon monoxide (CO) may enter
the vehicle, resulting in loss of consciousness
and even death.
To assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind.
At the onset of winter, have your vehicle
winterproofed at a qualified specialist
workshop, e.g. at an authorized Mercedes-
Benz Center.
Driving with summer tires
Observe the notes in the "Winter operation"
section ( Y page 310).
Slippery road surfaces
GWARNING
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges.
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.
Drive particularly carefully on slippery road
surfaces. Avoid sudden acceleration, steering
and braking maneuvers. Do not use cruise
control or DISTRONIC PLUS.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
XShift the transmission to position N.
i
For more information on driving with
snow chains, see ( Y page 311).
Driving tips163Driving and parkingZ

conditions. Additionally, the driver must
provide the steering, braking and other driving
inputs necessary to remain in control of the
vehicle.
High-frequency sources such as toll stations,
speed measuring systems etc. can cause the
DISTRONIC PLUS system to temporarily
cease functioning.GWARNING
The DISTRONIC PLUS cannot take road and
traffic conditions into account. Only use the
DISTRONIC PLUS if the road, weather and
traffic conditions make it advisable to travel
at a constant speed.
GWARNING
Use of the DISTRONIC PLUS can be
dangerous on slippery roads. Rapid changes
in tire traction can result in wheel spin and
loss of control.
The DISTRONIC PLUS does not function in
adverse sight and distance conditions. Do not
use the DISTRONIC PLUS during conditions of
fog, heavy rain, snow or sleet.
GWARNING
The DISTRONIC PLUS cannot take weather
conditions into account. Switch off the
DISTRONIC PLUS or do not switch it on if:
R roads are slippery or covered with snow or
ice. The wheels could lose traction while
braking or accelerating, and the vehicle
could skid.
R the DISTRONIC PLUS system sensor covers
are dirty or visibility is diminished due to
snow, rain or fog, for example. The distance
control system functionality could be
impaired.
Always pay attention to surrounding traffic
conditions even while the DISTRONIC PLUS is
switched on. Otherwise, you may not be able
to recognize dangerous situations until it is
too late. This could cause an accident in which
you and/or others could be injured.
GWARNING
The "Resume" function should only be
operated if the driver is fully aware of the
previously set speed and wishes to resume
this particular preset speed.
GWARNING
Your undivided attention to street and traffic
conditions is necessary at all times whether
DISTRONIC PLUS is active or not.
The use of DISTRONIC PLUS can be
dangerous on winding roads or in heavy traffic
because conditions do not allow safe driving
at a constant speed.
DISTRONIC PLUS does not react to stationary
objects on the road (for example, a vehicle
stopped in traffic or an abandoned vehicle).
DISTRONIC PLUS likewise does not react to
oncoming vehicles.
Deactivate DISTRONIC PLUS:
R when changing to the right lane, if the
vehicles in the left lane are driving slower
R when driving into a filter lane or an
expressway exit
R in complex driving situations, for example
in construction sites on an expressway
In these situations DISTRONIC PLUS will
maintain the set speed if it is not deactivated.
DISTRONIC PLUS is intended only for
maintaining a set speed and a set distance
from the objects moving in front of the
vehicle.
GWARNING
An intermittent warning sounds and the
distance warning lamp · in the instrument
cluster is illuminated if the DISTRONIC PLUS
system calculates that the distance to the
vehicle ahead and your vehicle's current
speed indicate that the DISTRONIC PLUS will
not be capable of slowing the vehicle
sufficiently to maintain the preset following
distance, which creates a danger of a
collision.
Driving systems167Driving and parkingZ

monitoring range. This warning is always
given when a vehicle enters the blind spot
monitoring range from behind or from the
side. When you are passing another vehicle,
the warning is emitted only if the difference
in speed is less than 7 mph (12 km/h).
The yellow indicator lamp goes out if reverse
gear is engaged. In this event, Blind Spot
Assist is no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light.GWARNING
Blind Spot Assist is not active at speeds under
approximately 20 mph (30 km/h). The
indicator lamps in the exterior mirrors are
yellow. Vehicles in the monitoring range are
then not indicated.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognize dangers in time, cause an accident
and injure yourself and others.
Collision warning
If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the turn
signal, a double warning tone sounds. Red
warning lamp : flashes. If the turn signal
remains on, detected vehicles are indicated
by the flashing of red warning lamp :. There
are no further warning tones.
Switching on Blind Spot Assist
XMake sure that the radar sensor system
( Y page 210) and Blind Spot Assist
( Y page 207) are activated in the on-board
computer.XTurn the SmartKey to position 2 in the
ignition lock.
Warning lamps : light up red in the
exterior mirrors for approximately 1.5
seconds and then turn yellow.Lane Keeping Assist
Important safety notes
Lane Keeping Assist monitors the area in
front of your vehicle by means of a camera at
the top of the windshield. Lane Keeping Assist
detects lane markings on the road and warns
you before you leave your lane
unintentionally.
If you have chosen the (Y page 208) function
in the on-board computer and select as the
unit of measurement, Active Lane Keeping
Assist is active from speeds of 60 km/h. If
the display unit is selected, the assistance
range begins at 40 mph.
GWARNING
Lane Keeping Assist does not keep your
vehicle in its lane. It is only an aid and may
detect the lane markings on the road
incorrectly or not at all.
The system may be impaired or may not
function if:
R there is poor visibility, e.g. due to
insufficient illumination of the road, or due
to snow, rain, fog or spray.
R there is glare, e.g. from oncoming traffic,
the sun, or reflection from other vehicles.
R the windshield is dirty, fogged up or
covered, for instance by a sticker, in the
vicinity of the camera.
R several or no lane markings for a single lane
are present.
R the lane markings are worn away, dark or
covered up, e.g. by dirt or snow.
R the distance to the vehicle in front is too
small and the lane markings thus cannot be
detected.
R the lane markings on the road are unclear,
e.g. near roadworks.
R the lane markings change quickly, e.g.
lanes branch off, cross one another or
merge.
R the road is narrow and winding.
188Driving systemsDriving and parking

Lane Keeping Assist cannot detect road and
traffic conditions. It is not a substitute for
attentive driving. You are responsible for the
vehicle's speed, braking in good time, and
steering correctly. Always adapt your driving
style to suit the prevailing road and weather
conditions. Always pay attention to traffic
conditions and your surroundings. Otherwise,
you may fail to recognize dangers in time,
cause an accident and injure yourself and
others.
A warning can be given when a front wheel
passes over a lane marking. It will warn you
by means of intermittent vibration in the
steering wheel for up to 1.5 seconds.
Switching on Lane Keeping AssistXSymbol : appears in the multifunction
display.
Active Driving Assistance package
General notes
The Active Driving Assistance package
consists of DISTRONIC PLUS ( Y page 166),
Active Blind Spot Assist ( Y page 189) and
Active Lane Keeping Assist ( Y page 192).
Active Blind Spot Assist
Important safety notes
Active Blind Spot Assist uses a radar sensor
system to monitor the side areas of your
vehicle which are in back of the driver. A
warning display in the exterior mirrors draws
your attention to vehicles detected in the
monitored area. If you then switch on the
corresponding turn signal to change lane, you
will also receive an optical and audible
collision warning. If a risk of lateral collision
is detected, corrective braking may help you
avoid a collision. To support the course-
correcting brake application, Active Blind
Spot Assist also uses the forward-facing radar
sensor system. Active Blind Spot Assist
supports you from speeds of approximately
20 mph (30 km/h).GWARNING
Active Blind Spot Assist is only an aid, and
may detect vehicles/obstacles incorrectly or
not at all.
The system may be impaired or may not
function if:
R there is poor visibility, e.g. due to snow,
rain, fog or spray.
R the rear and/or front sensors are dirty.
Active Blind Spot Assist may not detect
narrow vehicles, such as motorcycles or
bicycles, or may only detect them too late. It
cannot detect vehicles that are overtaken at
a small distance and then enter the blind spot
area.
Active Blind Spot Assist cannot detect road
and traffic conditions. It is not a substitute for
attentive driving. You are responsible for the
vehicle's speed, braking in good time, and
steering correctly. Always adapt your driving
style to suit the prevailing road and weather
conditions. Always pay attention to traffic
conditions and your surroundings. Otherwise,
you may fail to recognize dangers in time,
cause an accident and injure yourself and
others.
i USA only:
This device has been approved by the FCC
as a “Vehicular Radar System”. The radar
sensor is intended for use in an automotive
radar system only. Removal, tampering, or
altering of the device will void any
warranties, and is not permitted by the
FCC. Do not tamper with, alter, or use in
any non-approved way.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
For Active Blind Spot Assist to assist you
when driving, the radar sensor system must
be activated ( Y page 210) and operational.
Driving systems189Driving and parkingZ