2018 MERCEDES-BENZ GLS SUV parking brake

Problems with the transmission
ProblemPossible causes/consequences andMSolutions
The transmission has
problems shifting gear.The transmission is losing oil.
XHave the transmission checked at a qualified specialist workshop
immediately.
7G-TRONIC:
The acceleration ability
is deteriorating.
The transmission no lon-
ger changes gear.The transmission is in emergency mode.
It is only possible to shift intosecondgear and reverse gear.
XStop the vehicle.
XShift the transmission to position P.
XSwitch off the engine.
XWait at least ten seconds before restarting the engine.
XShift the transmission to positionDor R.
If D is selected, the transmission shifts into secondgear; ifRis
selected, the transmission shifts into reverse gear.
XHave the transmission checked at a qualified specialist workshop
immediately.
9G-TRONIC:
The acceleration ability
is deteriorating.
The transmission no lon-
ger changes gear.The transmission is in emergency mode.
It is only partly possible to engage the gears or the transmission is in
position N.
XStop the vehicle.
XShift the transmission to position P.
XSwitch off the engine.
XWait at least ten seconds before restarting the engine.
XShift the transmission to positionDor R.
XHave the transmission checked at a qualified specialist workshop
immediately.
Transfer case
This section is only valid for vehicles with 4-
wheel drive (4MATIC). Power is always trans-
mitted to both axles.
!Performance tests may only be carried out
on a 2-axle dynamometer. The brake system
or transfer case could otherwise be damaged. Contact a qualified specialist workshop for a
performance test.
!Because ESP®is an automatic system, the
engine and ignition must be switched off
(SmartKey in position 0or 1or Start/Stop
button in position 0or 1) when the electric
parking brake is being tested on a brake dyna-
mometer (maximum 10 seconds).
Braking triggered automatically by ESP
®may
seriously damage the brake system.
!Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised, as
doing so will damage the transmission.
Refueling
Important safety notes
GWARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and explo-
sion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the auxiliary heating before refueling.
Refueling155
Driving and parking
Z

Problems with fuel and the fuel tank
ProblemPossible causes/consequences andMSolutions
Fuel is leaking from the
vehicle.GWARNING
The fuel line or the fuel tank is faulty.
Risk of explosion or fire.
XApply the electric parking brake.
XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, on vehicles with KEYLESS‑GO:
XOpen the driver's door.
The vehicle electronics are now in key position u. This is the same
as the SmartKey having been removed.
XDo not restart the engine under any circumstances.
XConsult a qualified specialist workshop.
The engine does not
start.The fuel tank of a vehicle with a diesel engine has been run completely
dry.
XRefuel the vehicle with at least 5.3 US qt (5 liters) of diesel.
XTurn the ignition on for approximately ten seconds (Ypage 140).
XStart the engine continuously for up to ten seconds until it runs
smoothly.
If the engine does not start:
XTurn the ignition on again for approximately ten seconds
(Ypage 140).
XStart the engine again continuously for up to ten seconds until it
runs smoothly.
If the engine does not start after three attempts:
XConsult a qualified specialist workshop.
The fuel filler flap cannot
be opened.The fuel filler flap is not unlocked.
XUnlock the vehicle (Ypage 77).
The SmartKey battery is discharged or nearly discharged.
XUnlock the vehicle using the mechanical key (Ypage 79).
The fuel filler flap is unlocked, but the opening mechanism is jammed.
XConsult a qualified specialist workshop.
DEF (BlueTEC vehicles only)
General notes
To function properly, BlueTEC exhaust gas after-
treatment must be operated with the reducing
agent DEF. Adding DEF is one of the tasks per-
formed during maintenance. When the supply of DEF is almost used up, the
Check Additive See Operator's Manual
message is shown in the multifunction display.
If you drive the vehicle faster than 10 mph
(16 km/h), the
Check Additive See Opera‐
tor's Manualmessage goes out after approx-
imately one minute.
158Refueling
Driving and parking

overfilling. DEF may leak if overfilled. Mercedes-
Benz offers a special disposable hose with over-
fill protection. You can obtain this from any
authorized Mercedes-Benz Center. DEF is avail-
able in a variety of containers and receptacles.
Only use the disposable hose with the
Mercedes-Benz DEF refill canisters.
DEF refill bottle
!Only screw on the DEF refill bottle hand-
tight. Otherwise, the thread of the DEF refill
bottle could be damaged and DEF could leak
out.
XUnscrew the protective cap from DEF refill
bottle :.
XPlace DEF refill bottle :on the filler neck as
shown and screw it on clockwise until hand-
tight.
XPress DEF refill bottle :towards the filler
neck.
The DEF tank is filled. This may take up to one
minute.
iWhen DEF refill bottle :is no longer
pressed, filling stops and the bottle may be
taken off again after being only partially emp-
tied.
XRelease DEF refill bottle :.
XTurn DEF refill bottle:counter-clockwise
and remove it.
XScrew the protective cap onto DEF refill bot-
tle : again.
DEF refill bottles are available at many gas sta-
tions or at a qualified specialist workshop. Refill
bottles without a threaded cap do not provide
overfill protection. DEF may leak if overfilled.
Mercedes Benz offers special refill bottles with a threaded seal. These are available at any author-
ized Mercedes-Benz Center.
Parking
Important safety notes
GWARNING
Flammable material such as leaves, grass or
twigs may ignite if they come into contact with
hot parts of the exhaust system or exhaust
gas flow. There is a risk of fire.
Park the vehicle so that no flammable mate-
rials come into contact with parts of the vehi-
cle which are hot. Take particular care not to
park on dry grassland or harvested grain
fields.
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking position P.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
!Always secure the vehicle correctly against
rolling away. Otherwise, the vehicle or its driv-
etrain could be damaged.
To ensure that the vehicle is secured against
rolling away unintentionally:
Rthe electric parking brake must be applied
Rthe transmission must be in position jand
the SmartKey must be removed from the igni- tion lock
Rthe front wheels must be turned towards the
curb on steep uphill or downhill gradients
Rthe empty vehicle must be secured at the
front axle with a wheel chock or similar, for
example, on uphill or downhill gradients
Ra laden vehicle must also be secured at the
rear axle with a wheel chock or similar, for
example, on uphill or downhill gradients
Parking161
Driving and parking
Z

Switching off the engine
GWARNING
The automatic transmission switches to neu-
tral position Nwhen 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.
XApply the electric parking brake.
XShift the transmission to position j.
XWith the SmartKey:turn the SmartKey to
position uin the ignition lock and remove it.
The immobilizer is activated.
XWith KEYLESS-GO:
Press the Start/Stop button (
Ypage 140)
The engine stops and all the indicator lamps in
the instrument cluster go out.
If you switch the engine off with the transmis-
sion in position korh, the automatic trans-
mission shifts to iautomatically.
If you then open the driver's or front-passenger
door, the automatic transmission shifts to j
automatically.
If you want the automatic transmission to
remain in neutral i, e.g. when having the vehi-
cle cleaned in an automatic, tow-through car
wash:
XVehicles with a SmartKey: switch on the
ignition.
XVehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock.
XInsert the SmartKey into the ignition lock.
XSwitch on the ignition.
XAll vehicles: depress the brake pedal and
keep it depressed.
XEngage neutral i.
XRelease the brake pedal.
XRelease the electric parking brake.
XSwitch off the ignition and leave the SmartKey
in the ignition lock.
iThe engine can be switched off in an emer-
gency while the vehicle is in motion by press-
ing and holding the Start/Stop button for
three seconds.
Electric parking brake
General notes
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking position P.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
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.
XIf this is the case, only park the vehicle on
level ground and secure it to prevent it rolling
away.
XShift the automatic transmission to position
j.
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.
iThe electric parking brake performs a func-
tion test at regular intervals while the engine
is switched off. The sounds that can be heard
while this is occurring are normal.
162Parking
Driving and parking

Emergency braking
The vehicle can also be braked during an emer-gency by using the electric parking brake.
XWhile driving, push handle :of the electric
parking brake.
The vehicle is braked for as long as the handle
of the electric parking brake is pressed. The
longer the electric parking brake handle is
depressed, the greater the braking force.
During braking:
Ra warning tone sounds
Rthe ReleasePark.Brakemessage appears
Rthe red F(USA only) or !(Canada
only) indicator lamp in the instrument cluster flashes
When the vehicle has been braked to a stand-
still, the electric parking brake is engaged.
Parking the vehicle for a long period
If you leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharging.
If you leave the vehicle parked for longer than six
weeks, the vehicle may suffer damage as a
result of lack of use.
XVisit a qualified specialist workshop and seek
advice.
iYou can obtain information about trickle
chargers from a qualified specialist work-
shop.
Driving tips
General notes
Important safety notes
GWARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving.
GWARNING
If you operate mobile communication equip-
ment when driving, you may be distracted
from the traffic situation. You could also lose
control of the vehicle. There is a risk of an
accident.
Only operate this equipment when the vehicle
is stationary.
Observe the legal requirements for the country
in which you are driving. Some jurisdictions pro-
hibit the driver from using a mobile phone while driving a vehicle.
If you make a call while driving, always use
hands-free mode. Only operate the telephone
when the traffic situation permits. If you are
unsure, pull over to a safe location and stop
before operating the telephone.
Bear in mind that at a speed of only 30 mph
(approximately 50 km/h), the vehicle covers a
distance of 44 ft (approximately 14 m)per sec-
ond.
Drive sensibly – save fuel
Observe the following tips to save fuel:
XThe tires should always be inflated to the rec-
ommended tire pressure.
XRemove unnecessary loads.
XRemove roof carriers when they are not nee-
ded.
XWarm up the engine at low engine speeds.
164Driving tips
Driving and parking

The ECO display consists of three sections, with
an inner and outer area. The sections corre-
spond to the following three categories:
:Acceleration(evaluation of all accel-
eration processes):
Rthe outer area fills up and the inner area lights up green: moderate
acceleration, especially at higher
speeds
Rthe outer area empties and the
inner area is gray: sporty acceler-
ation
;Coasting (evaluation of all decelera-
tion processes):
Rthe outer area fills up and the inner area lights up green: anticipatory
driving, keeping your distance and
early release of the accelerator.
The vehicle can coast without use
of the brakes.
Rthe outer area empties and the
inner area is gray: frequent heavy
braking
=Constant (continuous evaluation
over the entire journey):
Rthe outer area fills up and the inner area lights up green: constant
speed and avoidance of unneces-
sary acceleration and deceleration
Rthe outer area empties and the
inner area is gray: fluctuations in
speed
The three inner areas display the current driving
style and light up green as a result of a particu-
larly economical driving style. Depending on thedriving situation, up to two areas may light up
simultaneously.
At the beginning of the journey, the three outer
areas are empty and fill up as a result of eco-
nomical driving. A higher level indicates a more
economical driving style. If the three outer areas
are completely filled at the same time, the driver
has adopted the most economical driving style
for the selected settings and prevailing condi-
tions. The ECO display border lights up.
The ECO display does not indicate the actual fuel consumption. The additionally achieved range
displayed under Bonus fr. Start
does not
indicate a fixed consumption reduction. In addition to driving style, the actual consump-
tion is affected by other factors, such as:
Rload
Rtire pressure
Rcold start
Rchoice of route
Relectrical consumers switched on
These factors are not included in the ECO dis-
play.
An economical driving style specially requires
driving at moderate engine speeds.
Achieving a higher value in the categories
"Acceleration" and "Constant":
Robserve the gearshift recommendations.
Rdrive the vehicle in the Comfortdrive pro-
gram.
On long journeys at a constant speed, e.g. on the
highway, only the outer area for "constant" will
change.
The ECO display summarizes the driving style
from the start of the journey to its completion.
Therefore, there are more marked changes in
the outer areas at the start of a journey. On lon- ger journeys, there are fewer changes. For more
marked changes, perform a manual rest
(
Ypage 237).
For further information on the ECO display, see
(
Ypage 237).
Brakes
Important safety notes
GWARNING
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 to a
lower gear in good time. This allows you to
take advantage of the engine's braking effect.
166Driving tips
Driving and parking

This helps you to avoid overheating the
brakes and wearing them out excessively.
When you take advantage of engine braking, a
drive wheel may not turn for some time, e.g.
on a slippery road surface. This could cause
damage to the drive train. This type of damage is not covered by the Mercedes-Benz war-
ranty.
Do not depress the brake pedal continuously
while the vehicle is in motion, e.g. causing the
brakes to rub by constantly applying light pres-
sure to the pedal. This results in excessive and
premature wear to the brake pads.
Use the left-hand steering wheel paddle shifter
to shift into a lower gear in good time on long
and steep downhill gradients. This is especially
important if the vehicle is laden.
This also applies if you have activated cruise
control, the speed limiter or Distance Pilot
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.
Heavy and light loads
GWARNING
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 airflow 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 vehicle
washed, brake firmly while paying attention to
the traffic conditions. This will warm up the
brake discs, thereby drying them more quickly
and protecting them against corrosion.
Limited braking performance on salt-
treated roads
If you drive on salted roads, a layer of salt resi-
due may form on the brake discs and brake
pads. This can result in a significantly longer
braking distance.
RBrake occasionally to remove any possible
salt residue. Make sure that you do not
endanger other road users when doing so.
RCarefully depress the brake pedal and the
beginning and end of a journey.
RMaintain a greater distance to the vehicle
ahead.
Servicing the brakes
!The brake fluid level may be too low, if:
Rif the red brake warning lamp lights up in
the instrument cluster and
Ryou hear a warning tone while the engine is
running
Observe additional warning messages in the
multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked immediately.
Consult a qualified specialist workshop to
arrange this.
!A function or performance test should only
be carried out on a 2-axle dynamometer. If
you wish to operate the vehicle on such a
dynamometer, please consult a qualified spe-
cialist workshop in advance. You could oth-
erwise 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 0or 1or Start/Stop
button in position 0or 1) when the electric
Driving tips167
Driving and parking
Z

parking brake is being tested on a brake dyna-
mometer (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 qualified spe-
cialist workshop.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
If the brake system has only been subject to
moderate loads, you should test the functional-
ity of your brakes at regular intervals. To do so,
depress the brake pedal firmly when driving at a high speed. This improves the grip of the brake
pads.
You can find a description of Brake Assist (BAS)
on (
Ypage 67) or of BAS PLUS on (Ypage 72).
Mercedes-Benz recommends that you only have
brake pads/linings installed on your vehicle
which have been approved for Mercedes-Benz
vehicles or which correspond to an equivalent
quality standard. Brake pads/linings which have
not been approved for Mercedes-Benz vehicles
or which are not of an equivalent quality could
affect your vehicle's operating safety.
Mercedes-Benz recommends that you only use
brake fluid that has been specially approved for
your vehicle by Mercedes-Benz, or which corre-
sponds to an equivalent quality standard. Brake
fluid which has not been approved for
Mercedes-Benz vehicles or which is not of an
equivalent quality could affect your vehicle's
operating safety.
High-performance brake system
(Mercedes-AMG vehicles)
The high-performance brake system is designed
for heavy loads. This may lead to noise when
braking. This will depend on:
RSpeed
RBraking force
REnvironmental conditions, such as tempera-
ture and humidity
The wear of individual components of the brake
system, such as the brake pads/linings or brake
discs, depends on the individual driving style
and operating conditions.
For this reason, it is impossible to state a mile-
age that will be valid under all circumstances. An
aggressive driving style will lead to high wear. You can obtain further information about this
from your authorized Mercedes-Benz Center.
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.
Keep this in mind, and adapt your driving and
braking accordingly during this break-in period.
Excessive heavy braking results in correspond-
ingly high brake wear. Observe the #brake
wear warning lamp in the instrument cluster and
note any brake status messages in the multi-
function display. Especially for high perform-
ance driving, it is important to maintain and have
the brake system checked regularly.
Driving on wet roads
Hydroplaning
If water has accumulated to a certain depth on
the road surface, there is a danger of hydro-
planing occurring, even if:
Ryou drive at low speeds.
Rthe tires have adequate tread depth.
For this reason, in the event of heavy rain or in
conditions in which hydroplaning may occur,
you must drive in the following manner:
Rlower your speed.
Ravoid ruts.
Ravoid sudden steering movements.
Rbrake carefully.
Driving on flooded roads
!Do not drive through flooded areas. Check
the depth of any water before driving through it. Drive slowly through standing water. Oth-
erwise, water may enter the vehicle interior or
the engine compartment. This can damage
the electronic components in the engine or
the automatic transmission. Water can also
be drawn in by the engine's air suction nozzles
and this can cause engine damage.
iVehicles with the AIRMATIC package:
select the raised vehicle level before driving
through a body of water.
168Driving tips
Driving and parking