engine MERCEDES-BENZ GL-Class 2015 X166 Service Manual

0047
0063
Left-hand standing lamps
0048 0064
Right-hand standing lamps
0049 0060
Parking lamps, license plate and
instrument cluster lighting
004A 0058
Automatic headlamp mode, control-
led by the light sensor
004B 0058
Low-beam/high-beam headlamps
0084 005E
Rear fog lamp
Even if the light sensor does not detect that it is dark, the parking lamps and low-beam
headlamps switch on when the ignition is
switched on and the light switch is set to the 0058 position. This is a particularly useful
function in the event of rain and fog.
X To switch on the low-beam headlamps:
turn the SmartKey in the ignition lock to
position 2or start the engine.
X Turn the light switch to 0058.
The green 0058indicator lamp in the instru-
ment cluster lights up.
Rear fog lamp 0047
0063
Left-hand standing lamps
0048 0064
Right-hand standing lamps 0049
0060
Parking lamps, license plate and
instrument cluster lighting
004A 0058
Automatic headlamp mode, control-
led by the light sensor
004B 0058
Low-beam/high-beam headlamps
0084 005E
Rear fog lamp
The rear fog lamp improves visibility of your
vehicle for the traffic behind in the event of
thick fog. Please take note of the country-
specific regulations for the use of rear fog
lamps.
X To switch on the rear fog lamps: turn the
SmartKey in the ignition lock to position 2
or start the engine.
X Turn the light switch to 0058or0058.
X Press the 005Ebutton.
The yellow 005Eindicator lamp in the
instrument cluster lights up.
X To switch off the rear fog lamp: press the
005E button.
The yellow 005Eindicator lamp in the
instrument cluster goes out.
Parking lamps ! If the battery has been excessively dis-
charged, the parking lamps or standing
lamps are automatically switched off to
enable the next engine start. Always park
your vehicle safely and sufficiently lit
according to legal standards. Avoid the
continuous use of the 0060parking lamps
for several hours. If possible, switch on the
0064 right or the 0063left standing lamp. 130
Exterior lightingLights and windshield wipers

High-beam headlamps
0043
High-beam headlamps
0044 Turn signal, right
0087 High-beam flasher
0085 Turn signal, left
X To switch on the high-beam headlamps:
turn the SmartKey in the ignition lock to
position 2or start the engine.
X Turn the light switch to 0058or0058.
X Press the combination switch beyond the
pressure point in the direction of arrow 0043.
In the 0058position, the high-beam head-
lamps are only switched on when it is dark
and the engine is running.
The blue 0057indicator lamp in the instru-
ment cluster lights up when the high-beam headlamps are switched on.
X To switch off the high-beam head-
lamps: move the combination switch back
to its normal position.
The blue 0057indicator lamp in the instru-
ment cluster goes out.
i Vehicles with Adaptive Highbeam Assist:
when Adaptive Highbeam Assist is active, it controls activation of the high-beam head-
lamps (Y page 134). High-beam flasher 0043
High-beam headlamps
0044 Turn signal, right
0087 High-beam flasher
0085 Turn signal, left
X To switch on: turn the SmartKey in the
ignition lock to position 1or 2or start the
engine.
X Pull the combination switch in the direction
of arrow 0087. Hazard warning lamps
X
To switch on the hazard warning lamps:
press button 0043.
All turn signals flash. If you now switch on a turn signal using the combination switch,
only the turn signal lamp on the corre-
sponding side of the vehicle will flash.
X To switch off the hazard warning lamps:
press button 0043.132
Exterior lightingLights and windshield wipers

0083
003D To switch the right-hand front read-
ing lamp on/off
0084 To switch the automatic interior lighting
control on
X To switch the front interior lighting on:
set the switch to the 004Aposition.
X To switch the interior lighting off: set the
switch to the 0033position or (if the door is
closed) to the center position.
X To switch the rear interior lighting on/
off: press the 0042button.
X To switch the reading lamps on/off:
press the 003Dbutton. Crash-responsive emergency lighting
The interior lighting is activated automatically
if the vehicle is involved in an accident.
X To switch off the crash-responsive
emergency lighting: press the hazard
warning lamp button.
or X Lock and then unlock the vehicle using the
SmartKey. Replacing bulbs
Important safety notes
G
DANGER
Xenon bulbs carry a high voltage. You can get an electric shock if you remove the cover of
the Xenon bulb and touch the electrical con-
tacts. There is a risk of fatal injury.
Never touch the parts or the electrical con-
tacts of the Xenon bulb. Always have work on
the Xenon bulbs carried out at a qualified spe-
cialist workshop.
If your vehicle is equipped with Xenon bulbs,
you can recognize this by the following: the
cone of light from the Xenon bulbs moves
from the top to the bottom and back again
when you start the engine. For this to be observed, the lights must be switched on
before starting the engine. G
WARNING
Bulbs, lamps and connectors can get very hot when operating. If you change a bulb, you
could burn yourself on these components.
There is a risk of injury.
Allow these components to cool down before changing a bulb.
Do not use a bulb that has been dropped or if
its glass tube has been scratched.
The bulb may explode if:
R you touch it
R it is hot
R you drop it
R you scratch it
Only operate bulbs in enclosed lamps
designed for that purpose. Only install spare
bulbs of the same type and the specified volt- age.
Marks on the glass tube reduce the service
life of the bulbs. Do not touch the glass tube
with your bare hands. If necessary, clean the
glass tube when cold with alcohol or spirit and
rub it off with a lint-free cloth.
Protect bulbs from moisture during opera-
tion. Do not allow bulbs to come into contact
with liquids.
There are bulbs other than the Xenon bulbs
that you cannot replace. Replace only the
bulbs listed (Y page 138). Have the bulbs that
you cannot replace yourself changed at a
qualified specialist workshop.
If you require assistance changing bulbs, con- sult a qualified specialist workshop.
If the new bulb still does not light up, consult
a qualified specialist workshop.
Bulbs and lamps are an important aspect of
vehicle safety. You must therefore make sure that these function correctly at all times.
Have the headlamp setting checked regularly. Replacing bulbs
137Lights and windshield wipers Z

Problems with the windshield wipers
Problem
Possible causes/consequences and
0050
0050Solutions The windshield wipers
are jammed. Leaves or snow, for example, may be obstructing the windshield
wiper movement. The wiper motor has been deactivated.
X For safety reasons, you should remove the SmartKey from the
ignition lock.
or X Switch off the engine using the Start/Stop button and open the
driver's door.
X Remove the cause of the obstruction.
X Switch the windshield wipers back on. The windshield wipers
fail completely. The windshield wiper drive is malfunctioning.
X Select another wiper speed on the combination switch.
X Have the windshield wipers checked at a qualified specialist
workshop. Windshield wipers
143Lights and windshield wipers Z

Useful information
i This Operator's Manual describes all
models and all standard and optional equip- ment 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 Read the information on qualified special-
ist workshops (Y page 29). Overview of climate control systems
General notes
Observe the settings recommended on the
following pages. The windows could other-
wise fog up.
To prevent the windows from fogging up:
R switch off climate control only briefly
R switch on air-recirculation mode only
briefly
R switch on the cooling with air dehumidifi-
cation function
R switch on the defrost windshield function
briefly, if required
Climate control regulates the temperature
and the humidity in the vehicle interior and
filters undesirable substances out of the air.
Climate control can only be operated when
the engine is running. Optimum operation is
only achieved with the side windows and roof closed.
The residual heat function can only be acti-
vated or deactivated with the ignition
switched off (Y page 161).
i Ventilate the vehicle for a brief period
during warm weather, e.g. using the con-
venience opening feature (Y page 97).
This will speed up the cooling process and
the desired interior temperature will be
reached more quickly. i
The integrated filter filters out most par-
ticles of dust and soot and completely fil-
ters out pollen. It also reduces gaseous pol-
lutants and odors. A clogged filter reduces the amount of air supplied to the vehicle
interior. For this reason, you should alwaysobserve the interval for replacing the filter,which is specified in the Maintenance
Booklet. As it depends on environmental
conditions, e.g. heavy air pollution, the
interval may be shorter than stated in the
Maintenance Booklet.
i It is possible that the residual heat func-
tion may be activated automatically an hour
after the SmartKey has been removed in
order to dry the air-conditioning system.
The vehicle is then ventilated for 30
minutes. 146
Overview of climate control systemsClimate control

0087
To direct the airflow through the rear air vents
0085 To direct the airflow through the footwell vents Optimum use of dual-zone automatic
climate control
The following contains notes and recommen-
dations on optimum use of the dual-zone
automatic climate control.
R Activate climate control using the 0058and
005A/0056 buttons. The indicator lamps in
the 0058 and005A/0056 buttons light up.
R Set the temperature to 72 ‡ (22 †).
R Only use the "Windshield defrosting" func-
tion 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 oth-
erwise fog up, since no fresh air is drawn
into the vehicle in air-recirculation mode.
R Use the ZONE function to adopt the tem-
perature settings on the driver's side for
the front-passenger side as well. The indi-
cator lamp above the 00D6button goes
out.
R Vehicles with COMAND: if you change the
settings of the climate control system, the
climate status display appears for approx-
imately three seconds at the bottom of the
screen in the COMAND display. See also
the separate COMAND operating instruc-
tions. You will see the current settings of
the various climate control functions.
During automatic engine switch-off, the cli-
mate control system only operates at a
reduced capacity. If you require the full cli-
mate control output, you can switch off the
ECO start/stop function by pressing the ECO
button (Y page 173). Overview of climate control systems
149Climate control

0079
To switch rear-compartment climate control on/off (Y page 154)
007A To reduce the airflow (Y page 158)Optimum use of 3-zone automatic cli-
mate control
The following contains instructions and rec-
ommendations to enable you to get the most
out of your 3-zone automatic climate control.
R Activate climate control using the 0058and
005A/0056 buttons. The indicator lamps
above the 0058and005A/0056 buttons
light up.
R 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" func-
tion 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 oth-
erwise fog up, since no fresh air is drawn
into the vehicle in air-recirculation mode.
R Use the ZONE function to adopt the tem-
perature 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 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 deac- tivated with the ignition switched off.
R Vehicles with COMAND: if you change the
settings of the climate control system, the
climate status display appears for approx-
imately three seconds at the bottom of the
screen in the COMAND display. See also
the separate COMAND operating instruc-
tions. You will see the current settings of
the various climate control functions. During automatic engine switch-off, the cli-
mate control system only operates at a
reduced capacity. If you require the full cli-
mate control output, you can switch off the
ECO start/stop function by pressing the ECO
button (Y page 173). Operating the climate control sys-
tems
Switching climate control on/off
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
i Switch on climate control primarily using
the 0058 button (Y page 156).
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 2in the igni-
tion lock (Y page 167).
X To activate: press the0058button.
The indicator lamp in the 0058button lights
up. Airflow and air distribution are set to
automatic mode.
or
X Press the 0078button.
The indicator lamp in the 0078button goes
out. The previously selected settings are
restored.
X To deactivate: press the0078button.
The indicator lamp in the 0078button lights
up. 154
Operating the climate control systemsClimate control

Activating/deactivating cooling with
air dehumidification
General notes If you deactivate the "Cooling with air-dehu-
midification" function, the air inside the vehi-
cle will not be cooled. The air inside the vehi-
cle will also not be dehumidified. The win-
dows can fog up more quickly. Therefore, only deactivate the "Cooling with air-dehumidifi-
cation" function briefly.
The "Cooling with air dehumidification" func-
tion is only available when the engine is run-
ning. The air inside the vehicle is cooled and
dehumidified according to the temperature
selected.
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 malfunc- tion.
Activating/deactivating Example:
005Abutton
X To activate: press the005A/0056 button.
The indicator lamp in the 005A/0056but-
ton lights up.
X To deactivate: press the005A/0056 but-
ton.
The indicator lamp in the 005A/0056but-
ton goes out. The "Cooling with air dehu-
midification" function has a delayed switch-
off feature. Operating the climate control systems
155Climate control

MAX COOL is only operational when the
engine is running.
X To activate: press the00C9button.
The indicator lamp in the button lights up.
X To activate: press off-road button 00C9
again.
The indicator lamp goes out. The previously
selected settings are restored.
When you activate MAX COOL, climate con-
trol switches to the following functions:
R maximum cooling
R maximum airflow
R air-recirculation mode on Defrosting the windows
Windows fogged up on the inside X
Activate the 005A/0056cooling with air
dehumidification function.
X Activate automatic mode 0058.
X If the windows continue to fog up, activate
the "windshield defrosting" function
(Y page 159).
i You should only select this setting until
the windshield is clear again.
Windows fogged up on the outside X
Press the 008Fbutton repeatedly until the
009C or009B symbol appears in the dis-
play.
i You should only select this setting until
the windshield is clear again. 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 auto-
matically after several minutes.
If the battery voltage is too low, the rear win-
dow defroster may switch off.
Switching on/off X
Turn the SmartKey to position 2in the igni-
tion lock (Y page 167).
X Press the 006Cbutton.
The indicator lamp in the 006Cbutton lights
up or goes out. 160
Operating the climate control systemsClimate control

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. Activating/deactivating air-recircula-
tion mode
General notes You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle
from outside. The air already inside the vehi-
cle will then be recirculated.
If you switch on air-recirculation mode, the
windows can fog up more quickly, in particu-
lar at low temperatures. Only use air-recircu-
lation mode briefly to prevent the windows
from fogging up.
Activating/deactivating The operation of air-recirculation mode is the
same for all control panels.
X Turn the SmartKey to position 2in the igni-
tion lock (Y page 167).
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 outside temperatures, air-recircula-
tion mode is automatically activated. When
air-recirculation mode is activated auto-
matically, the indicator lamp in the 0089
button 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 out-
side temperatures below approximately
41 ‡ (5 †)
R after approximately five minutes if cool-
ing with air dehumidification is deactiva-
ted
R after approximately 30 minutes at out-
side temperatures above approximately
41 ‡ (5 †) if the "Cooling with air dehu-
midification" function is activated Activating/deactivating the residual
heat function
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 station- ary vehicle for up to 30 minutes after the
engine has been switched off. The heating
time depends on the set interior temperature. Operating the climate control systems
161Climate control