engine MERCEDES-BENZ GLS 2018 Service Manual

Replacing the rear window wiper blade Removing a wiper blade X
Remove the SmartKey from the ignition lock. X
Fold wiper arm C away from the rear window
until it engages. X
Position wiper blade D at a right angle to
wiper arm C . X
Hold wiper arm C and press wiper blade D
in the direction of the arrow until it releases. X
Remove wiper blade D .
Installing a wiper blade X
Place new wiper blade D onto wiper arm C .X
Hold wiper arm C and press wiper blade D
in the opposite direction to the arrow until it
engages. X
Make sure that wiper blade D is seated cor-
rectly. X
Position wiper blade D parallel to wiper
arm C . X
Fold wiper arm C back onto the rear window.
Problems with the windshield wipers Problem
Possible causes/consequences and P Solutions
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 igni-
tion 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 work-
shop.124
Windshield wipers
Lights and windshield wipers

Overview of climate control systems
General notes Observe the settings recommended on the fol-
lowing pages. The windows could otherwise 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 dehumidifica-
tion 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.
The residual heat function can only be activated
or deactivated with the ignition switched off
( Y
page 135).
i Ventilate the vehicle for a brief period during
warm weather, e.g. using the convenience
opening feature ( Y
page 90). This will speed
up the cooling process and the desired inte-
rior temperature will be reached more
quickly. If you start the engine using your smartphone,
the last selected climate control setting is reac-
tivated ( Y
page 142).
i The integrated filter filters out most parti-
cles of dust and soot and completely filters
out pollen. It also reduces gaseous pollutants
and odors. A clogged filter reduces the
amount of air supplied to the vehicle interior.
Depending on the operating conditions and
environmental influences, the interval for
replacing the filter may be shorter than speci-
fied.
i Vehicles with ionization of the interior
air and air filter: in addition to ionization, the
vehicle has an air filter with anti-allergenic
properties that contribute to improved air fil-
tration.
i It is possible that under certain circumstan-
ces the residual heat function may be activa-
ted automatically an hour after the SmartKey
has been removed in order to dry the auto-
matic climate control. The vehicle is then ven-
tilated for 30 minutes.
Control panel for dual-zone automatic climate control
USA only
Front control panel
C
Sets the temperature, left ( Y
page 132)
D
Defrosts the windshield ( Y
page 133)Overview of climate control systems 125
Climate 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
C
Center air vent, left D
Center air vent, right

Notes on breaking-in a new vehicle
Important safety notes The sensor system of some driving and driving
safety systems adjusts automatically while a
certain distance is being driven after the vehicle
has been delivered or after repairs. Full system
effectiveness is not reached until the end of this
teach-in procedure.
New and replaced brake pads and discs only
reach their optimum braking effect after several
hundred kilometers of driving. Compensate for
this by applying greater force to the brake pedal.
The first 1000 miles (1500 km) The more you look after the engine when it is
new, the more satisfied you will be with its per-
formance in the future. R
You should therefore drive at varying vehicle
and engine speeds for the first 1000 miles
(1500 km). R
Avoid heavy loads, e.g. driving at full throttle,
during this period. R
Change gear in good time, before the tach-
ometer needle is

! Do not warm up the engine while stationary.
Pull away immediately. Avoid high engine
speeds and full throttle until the engine has
reached its operating temperature.
In vehicles with automatic transmission,
engage positions P and R only when the vehi-
cle is stationary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery roads.
You could otherwise damage the drive train.
! Mercedes-AMG vehicles: at low engine oil
temperatures below 68 ‡ (+20 †), the max-
imum engine speed is restricted in order to
protect the engine. To protect the engine and
maintain smooth engine operation, avoid driv-
ing at full throttle when the engine is cold.
Key positions
SmartKey
Z
To remove the SmartKeyG
Power supply for some consumers, such as
the windshield wipersH
Ignition (power supply for all consumers)
and drive positionI
To start the engine
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 notes
Vehicles with KEYLESS-GO are equipped with a
SmartKey featuring an integrated KEYLESS-GO
function and a detachable Start/Stop button. A check which periodically establishes a radio
connection between the vehicle and the Smart-
Key determines whether a valid SmartKey is in
the vehicle. This occurs, for example, when
starting the engine.
When you insert the Start/Stop button into the
ignition lock, the system needs approximately
two seconds recognition time. You can then use
the Start/Stop button.
Pressing the Start/Stop button several times in
succession corresponds to the different Smart-
Key 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 immedi-
ately.
To start the vehicle without actively using the
SmartKey: R
the Start/Stop button must be inserted in the
ignition lock R
the SmartKey must be in the vehicle R
the vehicle must not be locked with the
SmartKey or KEYLESS-GO ( Y
page 78).
Do not keep the SmartKey: R
with electronic devices, e.g. a mobile phone
or another SmartKey R
with metallic objects, e.g. coins or metal foil R
inside metallic objects, e.g. a metal case
This can impair the functionality of the KEY-
LESS-GO key.
Do not keep the KEYLESS-GO key in the tem-
perature-controlled cup holder ( Y
page 309).
Otherwise, the KEYLESS-GO key will not be rec-
ognized.
If you lock the vehicle with the SmartKey remote
control or with KEYLESS-GO, after a short time: R
you will not be able to switch on the ignition
with the Start/Stop button R
you will not be able to start the engine with the
Start/Stop button until the vehicle is
unlocked again
If you lock the vehicle centrally using the button
on the front door ( Y
page 83), you can continue
to start the engine with the Start/Stop button.
The engine can be switched off while the vehicle
is in motion by pressing and holding the Start/
Stop button for three seconds. This function
operates independently of the ECO start/stop
automatic engine switch-off function.140
Driving
Driving and parking

Key positions with KEYLESS- GO
C
Start/Sto p butto nD
Ignition loc k
As soo n as th e ignition is switched on , all th e
indicator lamps in th e instrumen t cluste r ligh t
up. Further information on situation s wher e an
indicator lamp either fails to go out after starting
th e engin e or lights up while driving
( Y
page 281).
If Start/Sto p butto n C has no t yet been
pressed, this correspond s to th e SmartKey
bein g remove d from th e ignition .X
To switch on th e power supply : press
Start/Sto p butto n C once.
The power suppl y is switched on . You can no w
activat e th e windshield wipers, for example .
The power suppl y is switched off again if:R
th e driver' s door is opened andR
you press Start/Sto p C butto n twice when in
this position X
To switch on th e ignition: press Start/Sto p
butto n C twice.
The ignition is switched on .
If you press Start/Sto p butto n C once when
in this position , th e ignition is deactivated
again .
Removing the Start/S top but ton
You can remove th e Start/Sto p butto n from th e
ignition loc k and start th e vehicl e as normal
usin g th e SmartKey.
It is possible to switch between KEYLESS-GO
mod e and ke y operation only when th e trans -
mission is in position ] .X
Remove Start/Sto p butto n C fr om ignition
loc k D . You do no t have to remove th e Start/Sto p but -
to n from th e ignition loc k when you leav e th e
vehicle. You should, however , always tak e th e
SmartKey wit h you when leaving th e vehicle. As
lon g as th e SmartKey is in th e vehicle:R
th e vehicl e can be started usin g th e Start /
Stop butto n R
th e electrically powered equipmen t can be
operate d
Starting the engine
Important safety notes
G WARNIN G
If children are lef t unsupervised in th e vehicle,
they could: R
open th e doors, thus endangering other
people or road users. R
get out and disrupt traffic. R
operate th e vehicle's equipment.
Additionally, children could set th e vehicl e in
motion if, for example , they:R
release th e parking brake. R
shiftin g th e automatic transmission out of
park positio n P R
Start th e engine.
Ther e is a ris k of an acciden t and injury.
When leaving th e vehicle, always tak e th e
SmartKey wit h you and loc k th e vehicle. Never
leav e children or animals unattended in th e
vehicle. Always keep th e SmartKey out of
reac h of children .
G WARNIN G
Combustion engines emit poisonous exhaust
gase s suc h as carbon monoxide. Inhalin g
these exhaust gase s leads to poisoning . Ther e
is a ris k of fatal injury. Therefore never leav e
th e engin e runnin g in enclosed spaces with-
out sufficien t ventilation .
G WARNIN G
Flammable materials introduce d throug h
environmental influence or by animals can Driving 141
Driving and parking Z

ignite if in contact with the exhaust system or
parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
General notes Vehicles with a gasoline engine: the catalytic
converter is preheated for up to 30 seconds
after a cold start. The sound of the engine may
change during this time.
Automatic transmission X
Shift the transmission to position ]
( Y
page 148).
The transmission position indicator on the
multifunction display shows ]
( Y
page 149).
i You can start the engine in transmission
position ] and \\ .
Starting procedure with the SmartKey X
To start a diesel engine: turn the SmartKey
to position H in the ignition lock
( Y
page 140).
The \( preglow indicator lamp in the instru-
ment cluster lights up. X
Turn the SmartKey to position I in the igni-
tion lock ( Y
page 140) and release it as soon
as the engine is running.
i Vehicles with a diesel engine: you can
start the engine without preglow if the engine
is warm.
Using KEYLESS-GO to start the engine The Start/Stop button can be used to start the
vehicle without inserting the SmartKey into the
ignition lock. The Start/Stop button must be
inserted in 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. X
Depress the brake pedal and keep it
depressed. X
Press the Start/Stop button once
( Y
page 140).
Vehicles with a gasoline engine: the engine
starts.
Vehicles with a diesel engine: preglow is
activated and the engine starts.
Starting procedure via smartphone Observe the important safety notes on starting
the engine ( Y
page 141).
You can also start your engine via your smart-
phone from outside the vehicle. In this case, the
previously selected climate control setting is
activated. In this way you can cool or heat the
interior of the vehicle before starting the jour-
ney.
Only start the engine via your smartphone if it is
safe to start and run the engine where your vehi-
cle is parked.
Observe the legal stipulations in the area where
your vehicle is parked. Engine start via smart-
phone may be limited to certain countries or
regions.
You can execute a maximum of two consecutive
starting attempts via your smartphone. If you
insert the SmartKey into the ignition lock, you
can carry out two more starting attempts.
Once you have started the engine, you can
switch the engine off via your smartphone at any
time.
You can only start the engine via your smart-
phone if: R
the SmartKey is in the ignition lock R
park position ] is selectedR
the accelerator pedal is not depressed R
the anti-theft alarm system is not activated R
the panic alarm is not activated R
the hazard warning lamps are switched off R
the hood is closed R
the doors are closed and locked R
the windows and sliding sunroof are closed
Also make sure that: R
the fuel tank is sufficiently filled R
the starter battery is sufficiently charged142
Driving
Driving and parking

G WARNING
Limbs could be crushed or trapped if the
engine is started unintentionally during ser-
vice or maintenance work. There is a risk of
injury.
Always secure the engine against uninten-
tional starting before carrying out mainte-
nance or repair work.
Make sure that the engine cannot be started via
your smartphone before carrying out mainte-
nance or repairs. You can prevent an engine
start via your smartphone, for example, if you: R
switch on the hazard warning lamps R
do not lock the doors R
open the hood
Pulling away
General notes
G WARNING
If the engine speed is above the idling speed
and you engage transmission position D or R ,
the vehicle could pull away suddenly. There is
a risk of an accident.
When engaging transmission position D or R ,
always firmly depress the brake pedal and do
not simultaneously accelerate.
Depress the accelerator carefully when pulling
away.
The vehicle locks centrally once you have pulled
away. The locking knobs in the doors drop down.
You can open the doors from the inside at any
time.
You can also deactivate the automatic locking
feature ( Y
page 244).
It is only possible to shift the transmission from
position P to the desired position if you depress
the brake pedal. Only then is the parking lock
released. If you do not depress the brake pedal,
the DIRECT SELECT lever can still be moved but
the parking lock remains engaged.
i Upshifts take place at higher engine speeds
after a cold start. This helps the catalytic con-
verter to reach its operating temperature
more quickly. Information on the automatic release of the
electric parking brake ( Y
page 163).
Pulling away with a trailer
To ensure that you do not roll backwards when
pulling away on an uphill slope, engage the elec-
tric parking brake. X
Press and hold handle C .
The electric parking brake continues to brake
and prevent the vehicle from rolling back-
wards.
The red I (USA only) or $ (Canada
only) indicator lamp in the instrument cluster
remains on. X
Depress the accelerator pedal. X
As soon as the vehicle/trailer combination is
held by the driving force of the engine, release
lever C .
the electric parking brake is released.
The red I (USA only) or $ (Canada
only) indicator lamp in the instrument cluster
goes out.
Hill start assist Hill start assist helps you when pulling away for-
wards or in reverse on an uphill gradient. It holds
the vehicle for a short time after you have
removed your foot from the brake pedal. This
gives you enough time to move your foot from
the brake pedal to the accelerator pedal and to
depress it before the vehicle begins to roll.
G WARNING
After a short time, hill start assist will no lon-
ger brake your vehicle and it could roll away.
There is a risk of an accident and injury.
Therefore, quickly move your foot from the
brake pedal to the accelerator pedal. Never Driving 143
Driving and parking Z

leave the vehicle when it is held by hill start
assist.
Hill start assist is not active if: R
you are pulling away on a level road or on a
downhill gradient. R
the transmission is in position N .R
the electric parking brake is applied. R
ESP ®
is malfunctioning.
ECO start/stop function
Introduction The ECO start/stop function switches the
engine off automatically if the vehicle is stopped
under certain conditions.
The engine starts automatically when the driver
wants to pull away again. The ECO start/stop
function thereby helps you to reduce the fuel
consumption and emissions of your vehicle.
Important safety notes
G WARNING
If the engine is switched off automatically and
you exit the vehicle, the engine is restarted
automatically. The vehicle may begin moving.
There is a risk of accident and injury.
If you wish to exit the vehicle, always turn off
the ignition and secure the vehicle against
rolling away.
General notes
C
ECO start/stop display
The ECO start/stop function is activated when-
ever you start the engine using the SmartKey or
the Start/Stop button.
If the engine has been switched off automati-
cally by the ECO start/stop function, the

Aut oma tic engine startThe engin e start s automatically if:R
you switch off th e ECO start/sto p function by
pressing th e ECO butto nR
in transmission position D or N th e brak e
pedal is release d and th e HOLD function is no t
active R
you depress th e accelerato r pedalR
you engage revers e gear RR
you mov e th e transmission out of position PR
you switch to th e Sport Plu s or Sport drive
program (Mercedes-AM G vehicles)R
you activat e manual gearshifting (Mercedes-
AM G vehicles)R
you switch to th e Offroa d drive program
(vehicles without Off-Road Engineering pack-
age) R
you switch to th e Offroa d or Offroa d Plu s
drive program (vehicles wit h Off-Road Engi-
neering package) R
you unfasten your seat belt or open th e driv-
er' s doorR
th e vehicl e start s to rol lR
th e brak e system require s thisR
th e temperature in th e vehicl e interior devi-
ate s from th e set rangeR
th e system detects moisture on th e wind-
shield when th e air-conditioning system is
switched on R
th e battery's condition of charge is to o low
Shifting th e transmission to position P does no t
start th e engine. Deactivating or activating the ECO
start/stop function All vehicles (excep t Mercedes-AM G veh i-
cles) X
To deactivate: press ECO butto n C .
Indicato r lamp D goe s out .X
To activate: press ECO butto n C .
Indicato r lamp D lights up.
If indicator lamp D is off , th e ECO start/sto p
function has been deactivated manually or as
th e result of a malfunction .
Mercedes-AM G veh icles
X
To deactivate: in th e Comfor t drive pro -
gram , press ECO butto n C .
or X
Activat e manual gearshifting ( Y
page 152).
or X
Switc h to th e Sport Plu s or Sport drive pro -
gram ( Y
page 147).
Indicato r lamp D goes out .X
To activate: press ECO butto n C .
Indicato r lamp D lights up. When th e
Sport Plu s or Sport drive program is activa-
ted, th e automatic transmission switches to
th e Comfor t drive program .Driving 145
Driving and parking Z