light MERCEDES-BENZ GL 2016 Repair Manual

Problems with the rear window defroster Problem
Possible causes/consequences and P Solutions
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 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 or deactivating
X
Turn the SmartKey to position 2 in the igni-
tion lock ( Y
page 165).X
To activate: press the

Activating or deactivatingX
To act iva te: press th e K or V but -
ton.
The indicator lamp in th e K or V
butto n lights up.
i The blowe r will run at a low spee d regard-
less of th e airflow setting .
i If you activat e th e residual heat function
at high temperatures , only th e ventilation
will be activated. The blowe r run s at
medium speed. X
To deacti va te: press th e K or V
button.
The indicator lamp in th e K or V
butto n goes out .
Residual heat is deactivated automatically: R
after approximately 30 minute sR
when th e ignition is switched onR
if th e battery voltag e drops
Setting the air vents
Import ant safety notes
G WARNIN G
Ver y hot or ver y cold air can flo w from th e air
vents . This could result in burn s or frostbit e in
th e immediat e vicinity of th e air vents . There
is a ris k of injury.
Mak e sur e that all vehicl e occupant s always
maintai n a sufficien t distanc e to th e air out -
lets. If necessary, redirect th e airflow to
another area of th e vehicl e interior. In order to en sure th e direct flo w of fr esh air
throug h th e air vents int o th e vehicl e interior,
pleas e observ e th e followin g notes:R
keep th e air inlet grille on th e hoo d and in
th e engin e compartmen t on th e front-
passenger side free of blockag es, suc h as
ice , sn ow or leav es. R
never cover th e air vents or air intake grilles
in th e vehicl e interior.
i Fo r virtually draft-free ventilation , adjust
th e sliders of th e air vents to th e center
position .
Setting the center air vents
C
Cente r air vent, lef tD
Cente r air vent, right

Pressing the Start/Stop button several times
in succession corresponds to the different
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 83).
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 349).
Otherwise, the KEYLESS-GO key will not be
recognized.
If you lock the vehicle with the SmartKey's
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 but-
ton on the front door ( Y
page 91), you can
continue to start the engine with the Start/
Stop button.
The engine can be switched off while the vehi-
cle 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 func-
tion.
Key positions with KEYLESS-GO
C
Start/Stop button D
Ignition lock
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. Further information on situations where
an indicator lamp either fails to go out after
starting the engine or lights up while driving
( Y
page 326).
If Start/Stop button C has not yet been
pressed, this corresponds to the key being
removed from the ignition. X
To switch on the power supply: press
Start/Stop button C once.
The power supply is switched on. You can
now activate the windshield wipers, for
example.
The power supply is switched off again if: R
the driver's door is opened and R
you press Start/Stop button C twice when
in this position X
To switch on the ignition: press Start/
Stop button C twice.
The ignition is switched on.
If you press Start/Stop button C once
when in this position, the ignition is deac-
tivated again.
Removing the Start/Stop button
You can remove the Start/Stop button from
the ignition lock and start the vehicle as nor-
mal using the SmartKey.166
Driving
Driving and parking

It is only possible to switch between KEY-
LESS-GO mode and SmartKey operation
when the transmission is in position P .X
Remove Start/Stop button C from ignition
lock D .
You do not have to remove the Start/Stop
button from the ignition lock when you leave
the vehicle. You should, however, always take
the SmartKey with you when leaving the vehi-
cle. As long as the SmartKey is in the vehicle: R
the vehicle can be started using the Start/
Stop button R
the electrically powered equipment can be
operated
Starting the engine
Important safety notes
G WARNING
If children are left unsupervised in the vehicle,
they could: R
open the doors, thus endangering other
people or road users. R
get out and disrupt traffic. R
operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake. R
shifting the automatic transmission out of
park position PR
Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
G WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There
is a risk of fatal injury. Therefore never leave the engine running in enclosed spaces with-
out sufficient ventilation.
G WARNING
Flammable materials introduced through
environmental influence or by animals can
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.
! Do not depress the accelerator when
starting the engine.
General notes Vehicles with a gasoline engine: the cata-
lytic converter is preheated for up 30 seconds
after a cold start. The sound of the engine may
change during this time.
Automatic transmission X
Shift the transmission to position P
( Y
page 174).
The transmission position display in the
multifunction display shows
P ( Y
page 174).
i You can start the engine in transmission
position P and N .
Starting procedure with the SmartKey X
To start a diesel engine : turn the Smart-
Key to position 2 in the ignition lock
( Y
page 165).
The \( preglow indicator lamp in the
instrument cluster lights up. X
Turn the SmartKey to position 3 in the igni-
tion lock and release it as soon as the
engine is running ( Y
page 165).
i Vehicles with a diesel engine: you can
start the engine without preglow if the
engine is warm. Driving 167
Driving and parking Z

The HOLD function can also be activated if the
engine has been switched off automatically. It
is then not necessary to continue applying the
brakes during the automatic stop phase.
When you depress the accelerator pedal, the
engine starts automatically and the braking
effect of the HOLD function is deactivated.
All vehicles (except Mercedes-AMG vehi-
cles): automatic engine switch-off can take
place a maximum of four times in a row (initial
stop, then three subsequent stops).
Mercedes-AMG vehicles: the number of
consecutive automatic engine switch-offs is
unlimited.
Automatic engine start The engine starts automatically if: R
you switch off the ECO start/stop function
by pressing the ECO button R
in transmission position D or N the brake
pedal is released and the HOLD function is
not active R
you depress the accelerator pedal R
you engage reverse gear RR
you move the transmission out of position
P R
you switch to drive program S or M
(Mercedes-AMG vehicles) R
you switch to an off-road program (except
Mercedes-AMG vehicles) R
you unfasten your seat belt or open the
driver's door R
the vehicle starts to roll R
the brake system requires this R
the temperature in the vehicle interior devi-
ates from the set range R
the system detects moisture on the wind-
shield when the air-conditioning system is
switched on R
the battery's condition of charge is too low
Shifting the transmission to position P does
not start the engine. Deactivating or activating the ECO
start/stop function All vehicles (except Mercedes-AMG vehi-
cles) X
To deactivate: press ECO button C .
Indicator lamp D goes out. X
To activate: press ECO button C .
Indicator lamp D lights up.
If the indicator lamp on the ECO button is off,
the ECO start/stop function has been deac-
tivated manually or as the result of a mal-
function.
Mercedes-AMG vehicles
X
To deactivate: in drive program C , press
ECO button C .
or X
Switch to drive program S or M
( Y
page 177).
Indicator lamp D goes out.170
Driving
Driving and parking

X
To activate: press ECO button C .
Indicator lamp D lights up. If drive pro-
gram S or M is active, the automatic trans-
mission switches to drive program C .
If the indicator lamp on the ECO button is off,
the ECO start/stop function has been deac-
tivated manually or as the result of a mal-
function.
Driving 171
Driving an d parking Z

Problem
Possible causes/consequences and P Solutions
Vehicles with a gaso-
line engine:
The engine is not run-
ning smoothly and is
misfiring. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system. X
Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic con-
verter and damage it. X
Have the cause rectified immediately at a qualified specialist
workshop.
The coolant tempera-
ture gage shows a value
above 248 ‡ (120 †). The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently. X
Stop as soon as possible and allow the engine and the coolant to
cool down. X
Check the coolant level ( Y
page 373). Observe the warning
notes as you do so and add coolant if necessary.
Automatic transmission
Important safety 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.
G WARNING
The automatic transmission switches to neu-
tral position N when you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P . Prevent the parked vehi-
cle from rolling away by applying the parking
brake. DIRECT SELECT lever
Overview of transmission positions
]
Park position with parking lock ^
Reverse gear \\
Neutral [
Drive
The DIRECT SELECT lever is on the right of the
steering column.
The DIRECT SELECT lever always returns to
its original position. The current transmission
position P , R , N or D appears in the transmis-
sion position display in the multifunction dis-
play ( Y
page 174).Automatic transmission 173
Driving and parking Z

The function of the electric parking brake is
dependent on the on-board voltage. If the on-
board voltage is low or there is a malfunction
in the system, it may not be possible to apply
the released parking brake. X
If this is the case, only park the vehicle on
level ground and secure it to prevent it roll-
ing away. X
Shift the automatic transmission to posi-
tion P .
It may not be possible to release an applied
parking brake if the on-board voltage is low or
there is a malfunction in the system. Contact
a qualified specialist workshop.
i The electric parking brake performs a
function test at regular intervals while the
engine is switched off. The sounds that can
be heard while this is occurring are normal.
Applying or releasing manually
X
To engage: push handle C .
When the electric parking brake is
engaged, the I (USA only) or $
(Canada only) red indicator lamp lights up
in the instrument cluster.
i The electric parking brake can also be
applied when the SmartKey is removed. X
To release: pull handle C .
The red I (USA only) or $ (Canada
only) indicator lamp in the instrument clus-
ter goes out.
i The electric parking brake can only be
released: R
if the SmartKey is in position 1 in the
ignition lock ( Y
page 165) or R
if the ignition was switched on using the
Start/Stop button
To ensure that you do not roll backwards
when pulling away on an uphill slope, engage
the electric parking brake ( Y
page 168).
Applying automatically The electric parking brake is applied auto-
matically: R
if DISTRONIC PLUS brings the vehicle to a
standstill or R
if the HOLD function is keeping the vehicle
stationary
In addition, at least one of the following con-
ditions must be fulfilled: R
the engine is switched off. R
the driver's door is open and the seat belt is
not fastened. R
the vehicle is stationary for a lengthy
period.
The red I (USA only) or $ (Canada
only) indicator lamp in the instrument cluster
lights up.
The electric parking brake is not automati-
cally engaged if the engine is switched off by
the ECO start/stop function.
Releasing automatically
The electric parking brake is released auto-
matically when all of the following conditions
are fulfilled: R
the engine is running. R
the transmission is in position D or R .R
the seat belt has been fastened. R
you depress the accelerator pedal. Parking 191
Driving and parking Z

The percent value is the average value of the
three bars. The three bars and the mean value
begin at the value of 50%. A higher percent-
age indicates a more economical driving
style.
The ECO display does not indicate the actual
fuel consumption. A fixed percentage count
in the ECO display does not indicate a fixed
consumption.
Apart from driving style, consumption is
dependent on many factors such as, e.g.: R
load R
tire pressure R
cold start R
choice of route R
electrical consumers switched on
These factors are not included in the ECO dis-
play.
The evaluation of your driving style is carried
out using the following three categories: R
Accel. (evaluation of all acceleration pro-
cesses): -
The bar fills up: moderate acceleration,
especially at higher speeds -
The bar empties: sporty acceleration R
Constant (assessment of driving behavior
at all times): -
The bar fills up: constant speed and
avoidance of unnecessary acceleration
and deceleration -
The bar empties: fluctuations in speed R
Coasting (assessment of all deceleration
processes): -
The bar fills up: anticipatory driving,
keeping your distance and early release
of the accelerator. The vehicle can coast
without use of the brakes. -
The bar empties: frequent braking
i An economical driving style specially
requires driving at moderate engine
speeds.
To achieve a higher value in the categories
Accel.
and Constant , observe the gear-
shift recommendations. i On long journeys at a constant speed, e.g.
on the highway, only the bar for Constant
will change.
i The ECO display summarizes the driving
characteristics from the start of the journey
to its completion. For this reason, the bars
change dynamically at the beginning of the
journey. On longer journeys, there are
fewer changes. For more dynamic changes,
carry out a manual reset.
For further information on the ECO display,
see ( Y
page 276).
Braking
Important safety notes
G WARNING
If you shift down on a slippery road surface in
an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface.
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 sur-
face. This could cause damage to the drive
train. This type of damage is not covered by
the Mercedes-Benz warranty.
Do not depress the brake pedal continuously
while the vehicle is in motion, e.g. causing the
brakes to rub by constantly applying light
pressure to the pedal. This results in exces-
sive and premature wear to the brake pads.194
Driving tips
Driving and parking

Heavy and light loads
G WARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This
increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately.
Drive on for a short while. This allows the air-
flow to cool the brakes more quickly.
Wet roads If you have driven for a long time in heavy rain
without braking, there may be a delayed reac-
tion from the brakes when braking for the first
time. This may also occur after the vehicle has
been washed or driven through deep water.
You then have to depress the brake pedal
more firmly. Maintain a greater distance from
the vehicle in front.
After driving on a wet road or having the vehi-
cle washed, brake firmly while paying atten-
tion to the traffic conditions. This will warm up
the brake discs, thereby drying them more
quickly and protecting them against corro-
sion.
Limited braking performance on salt-
treated roads
If you drive on salted roads, a layer of salt
residue may form on the brake discs and
brake pads. This can result in a significantly
longer braking distance. R
Brake occasionally to remove any possible
salt residue. Make sure that you do not
endanger other road users when doing so. R
Carefully depress the brake pedal and the
beginning and end of a journey. R
Maintain a greater distance to the vehicle
ahead.
Servicing the brakes
! If the red brake warning lamp lights up in
the instrument cluster and you hear a warn-
ing tone while the engine is running, the
brake fluid level may be too low. Observe
additional warning messages in the multi-
function display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked immedi-
ately. This work should be carried out at a
qualified specialist workshop.
! A function or performance test should
only be carried out on a 2-axle dynamom-
eter. If you are planning to have the vehicle
tested on such a dynamometer, contact an
authorized Mercedes-Benz Center to
obtain further information first. Otherwise,
you could damage the drive train or the
brake system.
! Because ESP ®
is an automatic system,
the engine and ignition must be switched
off (SmartKey in position 0 or 1 or Start/
Stop button in position 0 or 1 ) when the
electric parking brake is being tested on a
brake dynamometer (maximum
10 seconds).
Braking triggered automatically by ESP ®
may seriously damage the brake system.
All checks and maintenance work on the
brake system must be carried out at a quali-
fied specialist workshop. Consult a qualified
specialist workshop to arrange this.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop. Driving tips 195
Driving and parking Z