2019 MERCEDES-BENZ GLS SUV cooling

0076
Sets rear-compartment climate control to automatic (Y page 132)
0077 Directs the airflow through the rear air vents (Y page 133)
0078 Directs the airflow through the footwell vents (Y page 133)
0079 Switches the rear climate control on/off (Y page 131)
007A Reduces the airflow (Y page 133)Canada only
Front control panel
0043 Sets the temperature, left (Y page 132)
0044 Defrosts the windshield (Y page 133)
0087 Switches the ZONE function on/off (Y page 133)
0085 Switches cooling with air dehumidification on/off (Y page 131)
Switches the residual heat on or off (Y page 135)
0083 Switches the rear window defroster on/off (Y page 134)
0084 Sets the temperature, right (Y page 132)
006B Switches the rear climate control on/off
006C Activates/deactivates climate control (Y page 131)
006D Sets the air distribution (Y page 133)
006E Increases the airflow (Y page 133)
006F Reduces the airflow (Y page 133)
0070 Display
0071 Adjusts the climate mode settings (Y page 132)
0072 Switches air-recirculation mode on/off (Y page 135)
0073 Sets climate control to automatic (Y page 132)
Rear control panel
0074 Increases the airflow (Y page 133)
0075 Sets the temperature (Y page 132)
0076 Sets rear-compartment climate control to automatic (Y page 132)
0077 Directs the airflow through the rear air vents (Y page 133)
0078 Directs the airflow through the footwell vents (Y page 133)130
Overview of climate control systemsClimate control

0079
Switches the rear climate control on/off (Y page 131)
007A Reduces the airflow (Y page 133)Optimum use of automatic climate
control
The following contains notes and recommenda-
tions on optimum use of the dual-zone auto-
matic climate control or 3-zone automatic cli-
mate control.
R You can switch on climate control by using the
0058 and005A or0058 and0056 buttons.
The indicator lamps in the 0058and
005A buttons or the 0058and0056 buttons
light up.
R Vehicles with 3-zone automatic climate
control: in automatic mode, you can also use
the 00F0 button to set a climate mode
(FOCUS/MEDIUM/DIFFUSE). The MEDIUM
level is recommended.
R Set the temperature to 72 ‡ (22 †).
R Only use the "Windshield 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,
since no fresh air is drawn into the vehicle in
air-recirculation mode.
R Vehicles with 3-zone automatic climate
control: use the ZONE function to adopt the
temperature settings on the driver's side for
the front-passenger side and the rear com-
partment as well. The indicator lamp above
the 00D6 button goes out.
R Vehicles with 3-zone automatic climate
control: use the "residual heat" function if
you want to heat or ventilate the vehicle inte- rior when the ignition is switched off. The
residual heat function can only be activated or
deactivated with the ignition switched off.
R If you change the settings of the climate con-
trol system, the climate status display
appears for approximately three seconds at
the bottom of the screen in the multimedia
system display. You will see the current set-
tings of the various climate control functions.
During automatic engine switch-off, the climate
control system only operates at a reduced capa-
city. If you require the full climate control output, you can switch off the ECO start/stop function
by pressing the ECO button (Y page 145). Operating the climate control sys-
tems
Activating/deactivating climate con-
trol
General notes When the climate control is switched off, the air
supply and air circulation are also switched off.
The windows could fog up. Therefore, switch off
climate control only briefly
Activate climate control primarily using the
0058 button (Y page 132).
In the rear compartment, you can also switch
climate control on and off using the 0058and
0078 buttons.
Activating/deactivating X
Turn the SmartKey to position 0048in the igni-
tion lock (Y page 140).
X To activate: press the0058button.
The indicator lamp in the 0058button lights
up. Airflow and air distribution are set to auto-
matic mode.
X To deactivate: press the0078button.
The indicator lamp in the 0078button lights
up. Switching cooling with air dehumidi-
fication on/off
Activating/deactivating X
To activate: press the005Aor0056 button.
The indicator lamp in the 005Aor0056 button
lights up.
X To deactivate: press the005Aor0056 but-
ton.
The indicator lamp in the 005Aor0056 button
goes out. The "Cooling with air dehumidifica-
tion" function has a delayed switch-off fea-
ture. Operating the climate control systems
131Climate control

Problems with the "Cooling with air dehumidification" function
Problem
Possible causes/consequences and
0050
0050Solutions The indicator lamp in the
005A or0056 button
flashes three times or
remains off. The "Cool-
ing with air dehumidifi-
cation" function cannot
be switched on. Cooling with air dehumidification has been deactivated due to a mal-
function.
X Visit a qualified specialist workshop. Setting climate control to automatic
General notes In automatic mode, the set temperature is main-
tained automatically at a constant level. The
system automatically regulates the temperature of the dispensed air, the airflow and the air dis- tribution.
The "Cooling with air dehumidification" function
is activated automatically in automatic mode.
In the rear compartment, you can also switch
climate control for the rear seats to automatic
mode using the 0058button.
Automatic control X
Turn the SmartKey to position 0048in the igni-
tion lock (Y page 140).
X Set the desired temperature.
X To activate: press the0058button.
The indicator lamp in the 0058button lights
up. Automatic air distribution and airflow are
activated.
X To switch to manual mode: press the008F
button.
3-zone automatic climate control: when auto-
matic mode is activated, you can select a cli-
mate mode (Y page 132). Adjusting the climate mode settings
You can select the following climate mode set-
tings in automatic mode:
FOCUS high airflow, slightly cooler setting
MEDIUM medium airflow, standard setting
DIFFUSE low airflow, slightly warmer and draft- free setting X
Turn the SmartKey to position 0048in the igni-
tion lock (Y page 140).
X Press the 0058button.
X Press the 00F0button 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 driv-
er's and front-passenger sides.
X Turn the SmartKey to position 0048in the igni-
tion lock (Y page 140).
X To increase or decrease: turn control0043or
0084 counter-clockwise or clockwise
(Y page 125).
Only change the temperature setting in small
increments. Start at 72 ‡ (22 †).
3-zone automatic climate control You can select different temperature settings
for the driver's and front-passenger sides as well
as for the rear compartment.
X Turn the SmartKey to position 0048in the igni-
tion lock (Y page 140).
X To increase or decrease temperature in
the front compartment:
turn control0043or
0084 counter-clockwise or clockwise
(Y page 127).
Only change the temperature setting in small
increments. Start at 72 ‡ (22 †).
X To increase or reduce the temperature in
the rear compartment using the front con-
trol panel: press the00D6button.
The indicator lamp in the 00D6button goes
out. 132
Operating the climate control systemsClimate control

Activating/deactivating
X
Turn the SmartKey to position 0048in the igni-
tion lock (Y page 140).
X To activate: press the0064button.
The indicator lamp in the 0064button lights
up.
The climate control system switches to the
following settings:
R high airflow
R high temperature
R air distribution to the windshield and front
side windows
R air-recirculation mode off
X To deactivate: press the0064button.
The indicator lamp in the 0064button goes
out. The previously selected settings are
restored. Air-recirculation mode remains
deactivated. MAX COOL maximum cooling
The MAX COOL function is only available in vehi-
cles for the USA.
MAX COOL is only operational when the engine is running.
X To activate: press the00C9button.
The indicator lamp in the 00C9button lights
up.
X To deactivate: press the00C9button.
The indicator lamp in the 00C9button goes
out. The previously selected settings are
restored.
When you activate MAX COOL, climate control
switches to the following functions: R maximum cooling
R maximum airflow
R air-recirculation mode on Removing condensation from the win-
dows
Windows fogged up on the inside X
Activate the 005Aor0056 cooling with air
dehumidification function.
X Activate automatic mode 0058.
X If the windows continue to fog up, activate the
"windshield defrosting" function
(Y page 133).
i You should only select this setting until the
windshield is clear again.
Windows fogged up on the outside X
Activate the windshield wipers.
X Press the 008Fbutton repeatedly until the
009C or009B symbol appears in the display.
i You should only select this setting until the
windshield is clear again.
i If you clean the windows regularly, they do
not fog up so quickly. Rear window defroster
General notes The rear window defroster has a high current
draw. You should therefore switch it off as soon
as the rear window is clear. Otherwise, the rear
window defroster switches off automatically
after several minutes.
If the battery voltage is too low, the rear window defroster may switch off.
Activating/deactivating X
Turn the SmartKey to position 0048in the igni-
tion lock (Y page 140).
X Press the 006Cbutton.
The indicator lamp in the 006Cbutton lights
up or goes out. 134
Operating the climate control systemsClimate cont
rol

Problems with the rear window defroster
Problem
Possible causes/consequences and
0050
0050Solutions The rear window
defroster has deactiva-
ted prematurely or can-
not be activated. The battery has not been sufficiently charged.
X Switch off any consumers that are not required, e.g. reading lamps,
interior lighting or the seat heating.
When the battery is sufficiently charged, the rear window defroster can be activated again. Switching air-recirculation mode
on/off
General notes 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.
If you switch on air-recirculation mode, the win-
dows can fog up more quickly, in particular at
low temperatures. Only use air-recirculation
mode briefly to prevent the windows from fog-
ging up.
Activating/deactivating X
Turn the SmartKey to position 0048in the igni-
tion lock (Y page 140).
X To activate: press the0089button.
The indicator lamp in the 0089button lights
up.
i In the event of high pollution levels (3-zone
automatic climate control only) or at high out-
side temperatures, air-recirculation mode is
automatically activated. When air-recircula-
tion mode is activated automatically, the indi-
cator lamp in the 0089button is not lit.
Outside air is added after about 30 minutes.
X To deactivate: press the0089button.
The indicator lamp in the 0089button goes
out.
i Air-recirculation mode deactivates auto-
matically:
R after approximately five minutes at outside
temperatures below approximately 41 ‡
(5 †)
R after approximately five minutes if cooling
with air dehumidification is deactivated
R after approximately 30 minutes at outside
temperatures above approximately 41 ‡ (5 †) if the "Cooling with air dehumidifi-
cation" function is activated Switching the residual heat on or off
General notes The residual heat function is only available on
vehicles for Canada.
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 set interior temperature.
Activating/deactivating X
To activate: press the004Bor0056 button.
The indicator lamp in the 004Bor0056 button
lights up.
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.
X To deactivate: press the004Bor0056 but-
ton.
The indicator lamp in the 004Bor0056 button
goes out.
Residual heat is deactivated automatically:
R after approximately 30 minutes
R when the ignition is switched on
R if the battery voltage drops Ionization
Ionization is used to purify the air in the vehicle interior and attain an improved interior climate. Operating the climate control systems
135Climate control

The ionization of the interior air is odorless and
cannot be perceived directly in the vehicle inte- rior.
You can switch ionization on and off via the mul-
timedia system (see the Digital Operator's Man-
ual).
Ionization can only be operated when the auto-
matic climate control is switched on. The side air vent on the driver's side must be open. Setting the air vents
Important safety notes
G
WARNING
Very hot or very cold air can flow from the air vents. This could result in burns or frostbite in the immediate vicinity of the air vents. There
is a risk of injury.
Make sure that all vehicle occupants always
maintain a sufficient distance to the air out-
lets. If necessary, redirect the airflow to
another area of the vehicle interior.
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 grille on the hood and in the
engine compartment on the front-passenger
side free of blockages, such as ice, snow or
leaves.
R never cover the air vents or air intake grilles 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
0043
Center air vent, left
0044 Center air vent, right
0087 Center vent thumbwheel, right
0085 Center vent thumbwheel, left
X To open or close: turn thumbwheels0087
and 0085to the left or right. Setting the side air vents
Example
0043
Side window defroster vent
0044 Side air vent, left
0087 Thumbwheel for side air vent
X To open or close: turn thumbwheel0087up or
down. Setting the glove box air vent
! Close the air vent when heating the vehicle.
At high outside temperatures, open the air
vent and activate the "cooling with air dehu-
midification" function. Otherwise, tempera-
ture-sensitive items stored in the glove box
could be damaged. 136
Setting the air ventsClimate control

R
is affected more by strong crosswinds
R demands more sensitive steering
R has a larger turning circle
This could impair the handling characteristics.
When towing a trailer, always adjust your speed to the current road and weather conditions. Do
not exceed the maximum permissible speed for
your vehicle/trailer combination. Notes on towing a trailer
General notes !
If you have a trailer tow hitch retrofitted,
changes to the cooling system and drive train may be necessary, depending on the vehicle
type.
If you have a trailer tow hitch retrofitted,
observe the anchorage points on the chassis
frame.
R Do not exceed the legally prescribed maxi-
mum speed for vehicle/trailer combinations
in the relevant country.
This lowers the risk of an accident.
R Only install an approved trailer coupling on
your vehicle.
More information on availability and installa-
tion can be obtained at any qualified special-
ist workshop.
R The bumpers of your vehicle are not suitable
for installing detachable trailer couplings.
R Do not install hired trailer couplings or other
detachable trailer couplings on the bumpers
of your vehicle.
R If you no longer need the ball coupling,
remove it from the ball coupling recess. This
will reduce the risk of damage to the ball cou-
pling.
When towing a trailer, set the tire pressure on
the rear axle of the towing vehicle for the max-
imum load. You will find the values in the tire
pressure table in the fuel filler flap of the vehicle (Y page 371).
Please note that when towing a trailer, the fol-
lowing driving systems have limited availability
or are not available at all:
R Parking Assist PARKTRONIC (Y page 189)
R Blind Spot Assist (Y page 207)
R Active Lane Keeping Assist (Y page 212)On vehicles without level control, the height of
the ball coupling will alter according to the load
placed on the vehicle. If necessary, use a trailer
with a height-adjustable drawbar.
You will find installing dimensions and loads
under "Technical data" (Y page 392).
Driving tips Also observe the notes on pulling away with a
trailer (Y
page 143).
The maximum permissible speed for vehicle/
trailer combinations depends on the type of
trailer. Before beginning the journey, check the
trailer's documents to see what the maximum
permissible speed is for your trailer. Observe the
legally permissible maximum speed in the rele-
vant country.
For certain Mercedes-Benz vehicles, the maxi-
mum permissible rear axle load is increased
when towing a trailer. See "Technical data" to
find out whether this applies to your vehicle
(Y page 392). If you utilize any of the added
maximum rear axle load when towing a trailer,
the vehicle/trailer combination may not exceed
a maximum speed of 60 mph (100 km/h) for
reasons concerning the operating permit. This
also applies in countries in which the maximum
permissible speed for car/trailer combinations
is greater than 60 mph (100 km/h).
When towing a trailer, your vehicle's handling
characteristics will be different in comparison
with when driving without a trailer.
Use the left-hand steering wheel paddle shifter
to shift into a lower gear in good time on long
and steep downhill gradients.
This also applies if you have activated cruise
control or Active Distance Assist DISTRONIC.
This will use the braking effect of the engine, so that less braking will be required to maintain the
speed. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly. If you need additional
braking, depress the brake pedal repeatedly
rather than continuously.
Driving tips If the trailer swings from side to side:
X Do not accelerate.
X Do not counter-steer.
X Brake if necessary. 222
Towing a trailerDriving and parking

Display messages
Possible causes/consequences and
0050
0050Solutions 0049
Switch Off Lights Switch Off Lights You leave the vehicle and the lights are switched on. A warning tone
also sounds.
X Turn the light switch to the 0058position. 0049
Switch On Headlamps Switch On Headlamps You are driving with low-beam headlamps switched off.
X Turn the light switch to the 0058or0058 position. Adaptive Highbeam
Adaptive Highbeam
Assist Currently Assist Currently
Unavailable See Unavailable See
Operator's Manual Operator's Manual Adaptive Highbeam Assist is deactivated and temporarily inoperative.
Possible causes are:
R the windshield in the camera's field of vision is dirty
R visibility is impaired due to heavy rain, snow or fog
X Clean the windshield.
If the system detects that the camera is fully operational, the Adap‐
Adap‐
tive Highbeam Assist Now Available
tive Highbeam Assist Now Available message is displayed.
Adaptive Highbeam Assist is operational again. Adaptive Highbeam
Adaptive Highbeam
Assist Inoperative
Assist Inoperative Adaptive Highbeam Assist is faulty.
X
Visit a qualified specialist workshop. Engine
Display messages
Possible causes/consequences and
0050 0050Solutions 00BD
Check Check
Coolant
Coolant Level Level
See Operator's Man‐
See Operator's Man‐
ual ual The coolant level is too low.
! Avoid longer journeys when there is insufficient coolant in the
engine cooling system. You could otherwise damage the engine.
X Add coolant, observing the warning notes before doing so
(Y page 324).
If you have to add coolant frequently:
X Contact a qualified specialist workshop and have the engine cooling
system checked. 00AC The fan motor is defective.
X At coolant temperatures below 248 ‡(120 †), drive to the nearest
qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in moun-
tainous terrain and stop-and-go traffic. 258
Display messagesOn-board computer and displays