2018 MERCEDES-BENZ GLS SUV tow

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
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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
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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
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Familiarize yourself with the characteristics of
your vehicle and the gear shift operation before
driving through difficult terrain.
The following driving systems are specially
adapted to off-road driving:
RtheOff-road drive program (vehicles without
Off-Road Engineering package)
(
Ypage 219)
ROff-road andOff-road Plus drive programs
(vehicles with Off-Road Engineering package)
(
Ypage 220)
RLOW RANGE off-road gear (vehicles with the
Off-Road Engineering package)
(
Ypage 221)
RDifferential lock (vehicles with the Off-Road
Engineering package) (Ypage 221)
ROff-road ABS (Ypage 67)
ROff-road 4ETS (Ypage 70)
ROff-road ESP®(Ypage 71)
RAIRMATIC package (vehicle level)
(Ypage 188)
RDSR (Downhill Speed Regulation)
(Ypage 218)
Observe the following notes:
RStop the vehicle before starting to drive along
an off-road route. If necessary, select the off- road program (
Ypage 220) or shift to the
LOW RANGE off-road gear (Ypage 221).
RSelect a vehicle level that is suitable for the
terrain. To avoid damaging the vehicle, make
sure there is always sufficient ground clear-
ance.
RCheck that items of cargo and loads are
stowed safely and are well secured
(
Ypage 305).
RAlways keep the engine running and in gear
when driving on a downhill gradient. Activate
DSR (
Ypage 218).
RAlways keep the engine running and in gear
when driving down an incline.
RAdapt your speed to the terrain. The rougher,
steeper or more ruts on the terrain, the slower
your speed should be.
RDo not jump with the vehicle as this will inter- rupt the vehicle's propulsion.
RDrive with extreme care on unfamiliar off-road
routes where visibility is poor. For safety rea-
sons, get out of the vehicle first and survey
the off-road route.
RLook out for obstacles, such as rocks, holes,
tree stumps and furrows.
RTake care when turning on an uphill or down-hill slope or when driving across a slope. The
vehicle could otherwise tip over.
RAlways keep the doors, the tailgate, the side
windows and the sliding sunroof closed whilethe vehicle is in motion.
RDo not shift the automatic transmission to
position i.
RObserve the notes on off-road fording
(Ypage 169).
iInformation about retrofitting special all-ter-
rain tires is available from any qualified spe-
cialist workshop.
iDo not use the HOLD function when driving
off-road, on steep uphill or downhill gradients
or on slippery or loose surfaces. The HOLD
function cannot hold the vehicle on such sur-
faces.
Checklist before driving off-road
!If the engine oil warning lamp lights up while
the vehicle is in motion, stop the vehicle in a
safe place as soon as possible. Check the
engine oil level. The engine oil warning lamp
warning must not be ignored. Continuing the
journey while the symbol is displayed could
lead to engine damage.
XEngine oil level: check the engine oil level
and add oil if necessary.
When driving on steep gradients, the engine
oil level must be sufficiently high to ensure a
correct oil supply in the vehicle.
XDEF tank (BlueTEC vehicles): check the
level and add if necessary (Ypage 158).
XTire-changing tool kit: check that the jack is
working and make sure you have the lug
wrench, a robust tow cable and a folding
spade in the vehicle.
XWheels and tires: check the tread depth and
pressure of the tires.
XCheck for damage and remove any foreign
objects, e.g. small stones, from the wheels/
tires.
XReplace any missing valve caps.
XReplace dented or damaged wheels.
XRims: dented or bent rims can result in a loss
of tire pressure and damage the tire bead.
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Hilltops
When driving up an uphill gradient, slightly
reduce pressure on the accelerator immediately
before reaching the brow of the hill. Make use of
the vehicle's own impetus to travel over the
brow.
This style of driving prevents:
Rthe vehicle from lifting off the ground on the
brow of a hill
Rthe vehicle from traveling too quickly down
the other side
Driving downhill
RDrive slowly.
RDo not drive at an angle down steep inclines.
Steer into the line of fall and drive with the
front wheels aligned straight. Otherwise, the
vehicle could slip sideways, tip and rollover.
RShift to a lower gear using the left-hand pad-
dle shifter before tackling steep downhill gra-
dients.
RActivate DSR. If this is not sufficient, brake
gently. When doing so, make sure that the
vehicle is facing in the direction of the line of
fall.
RCheck that the brakes are working normally
after a long downhill stretch.
iThe special off-road ABS setting enables a
precise, brief and repeated locking of the
front wheels. This causes them to dig into
loose earth. Be aware that the front wheels
easily skid across the ground surface if com-
pletely braked and therefore lose their ability
to steer.
Driving systems
Intelligent Drive
Mercedes-Benz Intelligent Drive stands for inno-
vative driver assistance and safety systems
which enhance comfort and support the driver in critical situations. With these intelligent co-ordi-
nated systems Mercedes-Benz has set a mile-
stone on the path towards autonomous driving.
Mercedes-Benz Intelligent Drive embraces all
elements of active and passive safety in one well
thought out system – for the safety of the vehi-
cle occupants and that of other road users. Further information on driving safety systems
(
Ypage 66).
Cruise control
General notes
Cruise control maintains a constant road speed
for you. It brakes automatically in order to avoid
exceeding the set speed. You must select a
lower gear in good time on long and steep down-
hill gradients, especially if the vehicle is laden or
towing a trailer. By doing so, you will make use of
the braking effect of the engine. This relieves the
load on the brake system and prevents the
brakes from overheating and wearing too
quickly.
Use cruise control only if road and traffic con-
ditions make it appropriate to maintain a steady
speed for a prolonged period. You can store any
road speed above 20 mph (30 km/h).
iCruise control should not be activated when
driving off-road.
Important safety notes
If you fail to adapt your driving style, cruise con- trol can neither reduce the risk of an accident
nor override the laws of physics. Cruise control
cannot take into account the road, traffic and
weather conditions. Cruise control is only an
aid. You are responsible for the distance to the
vehicle in front, for vehicle speed, for braking in
good time and for staying in your lane.
Do not use cruise control:
Rin road and traffic conditions which do not
allow you to maintain a constant speed, e.g. in
heavy traffic or on winding roads
Ron slippery road surfaces. Braking or accel-
erating could cause the drive wheels to lose
traction and the vehicle could then skid
Rwhen there is poor visibility, e.g. due to fog,
heavy rain or snow
If there is a change of drivers, advise the new
driver of the speed stored.
174Driving systems
Driving and parking

Cruise control lever
:Activates or increases speed
;Activates or reduces speed
=Deactivates cruise control
?Activates at the current speed/last stored
speed
When you activate cruise control, the stored
speed is shown in the multifunction display for
five seconds.
Activation conditions
To activate cruise control, all of the following
activation conditions must be fulfilled:
Rthe electric parking brake must be released.
Ryou are driving faster than 20 mph (30 km/h).
RESP®must be active, but not intervening.
Rthe transmission must be in position D.
RDSR must be deactivated.
Rthe Offroad Plus drive program must be deac-
tivated (vehicles with the Off-Road Engineer-
ing package).
Storing, maintaining and calling up a
speed
Storing and maintaining a speed
XAccelerate the vehicle to the desired speed.
XBriefly press the cruise control lever up :or
down ?.
XRemove your foot from the accelerator pedal.
Cruise control is activated. The vehicle auto-
matically maintains the stored speed.
iCruise control may be unable to maintain
the stored speed on uphill gradients. The
stored speed is resumed when the gradient
evens out. Cruise control maintains the stored speed on downhill gradients by auto-
matically applying the brakes.
Storing or calling up a speed
GWARNING
If you call up the stored speed and it differs
from the current speed, the vehicle acceler-
ates or decelerates. If you do not know the
stored speed, the vehicle could accelerate or brake unexpectedly. There is a risk of an acci-
dent.
Pay attention to the road and traffic condi-
tions before calling up the stored speed. If you
do not know the stored speed, store the
desired speed again.
XBriefly pull the cruise control lever towards
you =.
XRemove your foot from the accelerator pedal.
Cruise control is operational and when first
activated stores the current speed or regu-
lates the speed of the vehicle to the stored
speed.
Setting a speed
Keep in mind that it may take a brief moment
until the vehicle has accelerated or braked to
the speed set.
XPress the cruise control lever up :for a
higher speed or down ;for a lower speed.
XTo adjust the set speed in 1 mph incre-
ments (1 km/h increments): briefly press
the cruise control lever up :or down ;to
the pressure point.
Every time the cruise control lever is pressed
up : or down ;the last speed stored is
increased or reduced.
XTo adjust the set speed in 5 mph incre-
ments (10 km/h increments): briefly press
the cruise control lever up :or down ;
beyond the pressure point.
Every time the cruise control lever is pressed
up : or down ;the last speed stored is
increased or reduced.
iCruise control is not deactivated if you
depress the accelerator pedal. For example, if
you accelerate briefly to overtake, cruise con-
trol adjusts the vehicle's speed to the last
speed stored after you have finished overtak-
ing.
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Deactivating cruisecontro l
There are severa lways to deactivat ecruise con-
trol:
XBriefly press th ecruise contro llever for-
ward s:.
or
XBrake.
Cruise contro lis automatically deactivated if:
Ryou engage th eelectric parking brake
Ryou are drivin gat les sthan 20 mph (30 km/h)
RESP®intervenes or you deactivate ESP®
Ryou activate DSR
Ryou activate the Offroad Plus program (vehi-
cles with the Off-Road Engineering package)
Ryou shift the transmission to position Nwhile
driving
If cruise control is deactivated, you will hear a
warning tone. You will see the Cruise Con‐
trol Offmessage in the multifunction display
for approximately five seconds.
iWhen you switch off the engine, the last
speed stored is cleared.
Distance Pilot DISTRONIC
General notes
Distance Pilot DISTRONIC regulates the speed
and automatically helps you maintain the dis-
tance to the vehicle detected in front. Vehicles
are detected with the aid of the radar sensor
system. Distance Pilot DISTRONIC brakes auto-
matically so that the set speed is not exceeded.
You must select a lower gear in good time on
long and steep downhill gradients, especially if
the vehicle is laden or towing a trailer. By doing so, you will make use of the braking effect of the
engine. This relieves the load on the brake sys-
tem and prevents the brakes from overheating
and wearing too quickly.
If Distance Pilot DISTRONIC detects that there is a risk of a collision, you will be warned visually
and acoustically. Without your intervention, Dis-
tance Pilot DISTRONIC cannot prevent a colli-
sion. An intermittent warning tone will then
sound and the distance warning lamp will light
up in the instrument cluster. Brake immediately
in order to increase the distance to the vehicle in front or take evasive action provided it is safe to
do so.
For Distance Pilot DISTRONIC to assist you
when driving, the radar sensor system must be
operational.
Distance Pilot DISTRONIC
ope
rates in the range
between 0 mph (0 km/h) and 120 mph
(200 km/h).
Do not use Distance Pilot DISTRONIC while driv-
ing on roads with steep gradients.
Since Distance Pilot DISTRONIC transmits radar
waves, it can resemble the radar detectors of
the responsible authorities. You can refer to the
relevant chapter in the Operator's Manual if
questions are asked about this.
iUSA only:
This device has been approved by the FCC as
a "Vehicular Radar System". The radar sensor
is intended for use in an automotive radar
system only. Removing, tampering with, or
altering the device will void any warranties,
and is not permitted by the FCC. Do not tam-
per with, alter, or use in any non-approved
way.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.
iCanada only: This device complies with
RSS-210 of Industry Canada. Operation is
subject to the following two conditions:
1. This device may not cause harmful inter-
ference, and
2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
Do not tamper with, alter or use in any non-
appro ved w
ay.
Any unauthorized modification to this device
could void the user's authority to operate the
equipment.
Important safety notes
GWARNING
Distance Pilot DISTRONIC does not react to:
Rpeople or animals
Rstationary objects on the road, e.g. stopped
or parked vehicles
Roncoming vehicles and crossing traffic
176Driving system s
Driving an d parking

As a result, Distance Pilot DISTRONIC may
neither give warnings nor intervene in such
situations. There is a risk of an accident.
Always pay careful attention to the traffic sit-uation and be ready to brake.
GWARNING
Distance Pilot DISTRONIC cannot always
clearly identify other road users and complex
traffic situations.
In such cases, Distance Pilot DISTRONIC may:
Rgive an unnecessary warning and then
brake the vehicle
Rneither give a warning nor intervene
Raccelerate or brake unexpectedly
There is a risk of an accident.
Continue to drive carefully and be ready to
brake, especially if Distance Pilot DISTRONIC
warns you.
GWARNING
Distance Pilot DISTRONIC brakes your vehicle with up to 50% of the maximum possible
deceleration. If this deceleration is not suffi-
cient, Distance Pilot DISTRONIC alerts you
with a visual and acoustic warning. There is a
risk of an accident.
Apply the brakes yourself in these situations
and try to take evasive action.
!When Distance Pilot DISTRONIC or the
HOLD function is activated, the vehicle
brakes automatically in certain situations.
To avoid damage to the vehicle, deactivate
DISTRONIC PLUS and the HOLD function in
the following or similar situations:
Rwhen towing the vehicle
Rin the car wash
The Distance Pilot DISTRONIC
Rcan neither reduce the risk of accident nor
override the laws of physics if you fail to adapt
your driving style.
Rcannot take into account road, weather or
traffic conditions.
Ris only an aid. You are responsible for the dis-
tance to the vehicle in front, for vehicle speed, for braking in good time and for staying in your
lane.
Do not use Distance Pilot DISTRONIC:
Rin road and traffic conditions which do not
allow you to maintain a constant speed, e.g. in
heavy traffic or on winding roads
Ron slippery road surfaces. Braking or accel-
erating could cause the drive wheels to lose
traction and the vehicle could then skid
Rin poor visibility, e.g. due to fog, heavy rain or
snow
Distance Pilot DISTRONIC may not detect nar-
row vehicles driving in front, e.g. motorcycles, or
vehicles driving on a different line.
In particular, the detection of obstacles can be
impaired if:
Rthere is dirt on the sensors or anything else
covering the sensors
Rthere is snow or heavy rain
Rthere is interference by other radar sources
Rthere are strong radar reflections, for exam-
ple, in parking garages
If Distance Pilot DISTRONIC no longer detects a
vehicle in front, it may unexpectedly accelerate
to the speed stored.
This speed may:
Rbe too high if you are driving in a turning lane
or an exit lane
Rbe so high when driving in the right-hand lane that you overtake vehicles in the left-hand
lane
Rbe so high when driving in the left-hand lane
that you overtake vehicles in the right-hand
lane
If there is a change of drivers, advise the new
driver of the speed stored.
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