climate control MERCEDES-BENZ GL 2012 Owner's Manual

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 d button.
The indicator lamp in the d button lights
up.
i Air-recirculation mode is activated
automatically at high outside
temperatures. When air-recirculation mode
is activated automatically, the indicator
lamp in the d button is not lit.
Outside air is added after about 30
minutes.
XTo switch off: press the d button.
The indicator lamp in the d 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 †)
i The air-recirculation mode is not
deactivated automatically at outside
temperatures above 79 ‡ (26 †). After
approximately 30 minutes, outside air is
added. 21
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 Á button.
The indicator lamp in the Á button lights
up.XTo switch off: press the Á button.
The indicator lamp in the Á button goes
out.21 Vehicles with automatic climate control144Operating the climate control systemClimate control

iResidual 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:Center air vent, left;Center air vent, right=Center vent thumbwheel, right?Center vent thumbwheel, leftXTo open/close: turn thumbwheels =
and ? to the right or left.
Setting the side air vents
XTo open/close: turn thumbwheel = to the
left or right.
i Side window defroster vent : is never
completely shut, even if side air vent ; is
shut.
Setting the air vents145Climate controlZ

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 control panel 22
When the climate control panel is switched
on/off, the air supply through the rear-
compartment air vents is also switched on/
off.
Center vents in the rear compartment (3rd row of
seats)
:Rear-compartment air vent, left;Rear-compartment air vent, right=Rear-compartment air vent thumbwheel,
right?Rear-compartment air vent thumbwheel,
leftXTo open/close: turn thumbwheel =
or ? up or down.Setting the B-pillar air vents:B-pillar air vent;B-pillar air vent=Thumbwheel for B-pillar air vent, rear?Thumbwheel for B-pillar air vent, frontXTo open/close: turn thumbwheel =
or ? up or down.22
Vehicles with automatic climate control.146Setting the air ventsClimate control

Maximum tire load : is the maximum
permitted weight for which the tire is
approved.
Further information on tire loads
( Y page 355).
Uniform Tire Quality Grading
Standards
Overview of Tire Quality Grading
Standards
The Uniform Tire Quality Grading is a U.S.
Government requirement. Their purpose is to
provide drivers with consistent and reliable
information regarding tire performance. Tire
manufacturers are required to grade tires
using three performance factors: tread
wear :, tire traction ;, and temperature
resistance =. Although not a Government of
Canada requirement, all tires made for sale in
North America have these grades branded on
the sidewall.
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
Where applicable, the tire grading
information can be found on the tire sidewall
between the tread shoulder and maximum
tire width.
For example:
Tread wearTractionTemperature200AAAAll passenger car tires must conform to the
statutory safety requirements in addition to
these grades.
Tread wear
The tread wear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified
U.S. government course. For example, a tire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm, due to variations in driving habits,
service practices and differences in road
characteristics and climate conditions.
Traction
GWARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
the tire's ability to stop on a wet surface as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance.
GWARNING
If ice has formed on the road, tire traction will
be substantially reduced. Under such weather
conditions, drive, steer and brake with
extreme caution.
The safe speed on a wet, snow covered or icy
road is always lower than on dry road
surfaces.
354Uniform Tire Quality Grading StandardsWheels and tires