tires MERCEDES-BENZ GLS 2017 User Guide

Never leave animals unattended in the vehi-
cle. Always secure animals properly during
the journey, e.g. use a suitable animal trans-
port box.
Driving safety systems
Overview of driving safety systems In this section, you will find information about
the following driving safety systems: R
ABS ( A nti-lock B raking S ystem)
( Y
page 63) R
BAS ( B rake A ssist S ystem) ( Y
page 64)R
Active Brake Assist ( Y
page 64)R
ESP ®
( E lectronic S tability P rogram)
( Y
page 67) R
EBD ( E lectronic B rake force D istribution)
( Y
page 69) R
ADAPTIVE BRAKE ( Y
page 69)R
Active Brake Assist with cross-traffic function
( Y
page 69) R
STEER CONTROL ( Y
page 72)
Important safety notes If you fail to adapt your driving style or if you are
inattentive, the driving safety systems can nei-
ther reduce the risk of an accident nor override
the laws of physics. Driving safety systems are
merely aids designed to assist driving. You are
responsible for maintaining the distance to the
vehicle in front, for vehicle speed, for braking in
good time, and for staying in lane. Always adapt
your driving style to suit the prevailing road and
weather conditions and maintain a safe distance
from the vehicle in front. Drive carefully.
The driving safety systems described only work
as effectively as possible when there is ade-
quate contact between the tires and the road
surface. Pay particular attention to the informa-
tion regarding tires, recommended minimum
tire tread depths etc. in the "Wheels and tires"
section ( Y
page 346).
In wintry driving conditions, always use winter
tires (M+S tires) and if necessary, snow chains.
Only in this way will the driving safety systems
described in this section work as effectively as
possible. ABS (Anti-lock Braking System)
General information ABS regulates brake pressure in such a way that
the wheels do not lock when you brake. This
allows you to continue steering the vehicle when
braking.
The % ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
ABS works from a speed of about 5 mph
(8 km/h), regardless of road-surface conditions.
ABS works on slippery surfaces, even when you
only brake gently.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 63).
G WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid-
ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp ( Y
page 277) and dis-
play messages which may be shown in the
instrument cluster ( Y
page 245).
Braking X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking sit-
uation is over. X
To make a full brake application: depress
the brake pedal with full force.
If ABS intervenes when braking, you will feel a
pulsing in the brake pedal.
The pulsating brake pedal can be an indication
of hazardous road conditions, and functions as a
reminder to take extra care while driving.Driving safety systems 63
Safety Z

are in the path of your vehicle for an extended
period of time.
If adaptive Brake Assist detects a risk of colli-
sion with the vehicle in front, it calculates the
braking force necessary to avoid a collision. If
you apply the brakes forcefully, adaptive Brake
Assist will automatically increase the braking
force to a level suitable for the traffic conditions.
Adaptive Brake Assist provides braking assis-
tance in hazardous situations at speeds above
4 mph (7 km/h). It uses radar sensor technology
to assess the traffic situation.
Up to a speed of approximately 155 mph
(25 0 km/ h) , Adaptive Brake Assist is capable of
reacting to moving objects that have already
been detected as such at least once over the
period of observation.
Up to a speed of approximately 44 mph
(70 km/ h) , Adaptive Brake Assist reacts to sta-
tionary obstacles.
If adaptive Brake Assist demands particularly
high braking force, preventative passenger pro-
tection measures (PRE-SAFE ®
) are activated
simultaneously ( Y
page 55).X
Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if: R
you release the brake pedal. R
there is no longer any danger of a collision. R
no obstacle is detected in front of your vehi-
cle.
Adaptive Brake Assist is then deactivated.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems ( Y
page 63).
G WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist can: R
intervene unnecessarily R
not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. Terminate the
intervention in a non-critical driving situation. G WARNING
Adaptive Brake Assist does not react: R
to people or animals R
to oncoming vehicles R
to crossing traffic R
when cornering
As a result, the Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause Brake Assist to intervene.
If adaptive Brake Assist is not available due to a
malfunction in the radar sensor system, the
brake system remains available with full brake
boosting effect and BAS.
ESP ®
(Electronic Stability Program)
General notes
i Observe the "Important safety notes" sec-
tion ( Y
page 63).
ESP ®
monitors driving stability and traction, i.e.
power transmission between the tires and the
road surface.
If ESP ®
detects that the vehicle is deviating from
the direction desired by the driver, one or more
wheels are braked to stabilize the vehicle. The
engine output is also modified to keep the vehi-
cle on the desired course within physical limits.
ESP ®
assists the driver when pulling away on
wet or slippery roads. ESP ®
can also stabilize
the vehicle during braking.
ETS/4ETS (Electronic Traction System)
4ETS traction control is part of ESP ®
.
Traction control brakes the drive wheels indi-
vidually if they spin. This enables you to pull
away and accelerate on slippery surfaces, for
example if the road surface is slippery on one
side. In addition, more drive torque is transfer-
red to the wheel or wheels with traction.
Traction control remains active, even if you
deactivate ESP ®
.66
Driving safety systems
Safety

Emergency braking
The vehicle can also be braked during an emer-
gency by using the electric parking brake. X
While driving, push handle C 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: R
a warning tone sounds R
the Release Park. Brake message appearsR
the red I (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. X
Visit a qualified specialist workshop and seek
advice.
i You can obtain information about trickle
chargers from a qualified specialist work-
shop. Driving tips
General notes
Important safety notes
G WARNING
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.
G WARNING
If you operate mobile communication equip-
ment while driving, you will be distracted from
traffic conditions. 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: X
The tires should always be inflated to the rec-
ommended tire pressure. X
Remove unnecessary loads. X
Remove roof carriers when they are not nee-
ded. X
Warm up the engine at low engine speeds. X
Avoid frequent acceleration or braking. X
Have all maintenance work carried out as
indicated by the service intervals in the Main-162
Driving tips
Driving and parking

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 ( Y
page 64) or of BAS PLUS on ( Y
page 69).
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: R
Speed R
Braking force R
Environmental 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: R
you drive at low speeds. R
the 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: R
lower your speed. R
avoid ruts. R
avoid sudden steering movements. R
brake 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.
i Vehicles with the AIRMATIC package:
select the raised vehicle level before driving
through a body of water.166
Driving tips
Driving and parking

Off-road fording
! Under no circumstances should you accel-
erate before entering the water. The bow
wave could cause water to enter and damage
the engine and other assemblies.
! Do not open any of the vehicle's doors while
fording. Otherwise, water could get into the
vehicle interior and damage the vehicle's
electronics and interior equipment. R
Establish how deep the water is and the char-
acteristics of the body of water before ford-
ing. R
Select the highest possible vehicle level. R
Shift to a lower gear using the left-hand steer-
ing wheel paddle shifter. R
Avoid high engine speeds. R
Enter and exit the water at a flat place and at
a steady walking pace. R
Drive slowly and at an even speed through the
water. R
Ensure that a bow wave does not form as you
drive. R
Do not stop and do not switch off the engine.
Water offers a high degree of resistance, and
the ground is slippery and in some cases
unstable. Therefore, it is difficult and danger-
ous to pull away in the water. R
Clean any mud from the tire tread after ford-
ing. R
Apply the brakes to dry them after fording.
Always observe the fording depth values
( Y
page 385).
Winter driving
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.
G DANGER
If the exhaust pipe is blocked or adequate
ventilation is not possible, poisonous gases such as carbon monoxide (CO) may enter the
vehicle. This is the case, e.g. if the vehicle
becomes trapped in snow. There is a risk of
fatal injury.
If you leave the engine or the auxiliary heating
running, make sure the exhaust pipe and area
around the vehicle are clear of snow. To
ensure an adequate supply of fresh air, open a
window on the side of the vehicle that is not
facing into the wind.
Have your vehicle winter-proofed at a qualified
specialist workshop at the onset of winter.
Drive particularly carefully on slippery road sur-
faces. Avoid sudden acceleration, steering and
braking maneuvers. Do not use cruise control or
Distance Pilot DISTRONIC.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed: X
Shift the transmission to position N .
When driving in snow with or without snow
chains, select driving program Slippery
( Y
page 145).
i Vehicles with a diesel engine: do not
cover the radiator, e.g. with a protective
cover. The measuring function of the on-
board diagnosis system may otherwise pro-
vide inaccurate values. Some of these values
are required by law and must therefore always
be accurate.
The outside temperature indicator is not
designed to serve as an ice-warning device and
is therefore unsuitable for that purpose.
Changes in the outside temperature are dis-
played after a short delay.
Indicated temperatures just above the freezing
point do not guarantee that the road surface is
free of ice. The road may still be icy, especially in
wooded areas or on bridges. You should pay
special attention to road conditions when tem-
peratures are around the freezing point.
For more information on driving with snow
chains, see ( Y
page 348).
For more information on driving with summer
tires, see ( Y
page 348).
Observe the notes in the "Changing a wheel"
section ( Y
page 366).Driving tips 167
Driving and parking Z

Off-road driving
Important safety notes
G WARNING
If you drive on a steep incline at an angle or
turn when driving on an incline, the vehicle
could slip sideways, tip and rollover. There is a
risk of an accident.
Always drive on a steep incline in the line of
fall (straight up or down) and do not turn the
vehicle.
G WARNING
Flammable material such as leaves, grass or
twigs may ignite if they come into contact with
hot parts of the exhaust system. There is a risk
of fire.
When driving off road or on unpaved roads,
check the vehicle's underside regularly. In
particular, remove parts of plants or other
flammable materials which have become
trapped. In the case of damage, contact a
qualified specialist workshop.
G WARNING
If the vehicle level is high, the vehicle center of
gravity is raised. This could cause the vehicle
to tip over more easily on uphill or downhill
gradients. There is a risk of an accident.
Select the lowest possible vehicle level.
! There is a risk of damage to the vehicle if: R
the vehicle becomes stuck, e.g. on a high
curb or an unpaved road R
you drive too fast over an obstacle, e.g. a
curb, speed bumps or a pothole in the road R
a heavy object strikes the underbody or
parts of the chassis
In situations like this, the body, the under-
body, chassis parts, wheels or tires could be
damaged without the damage being visible.
Components damaged in this way can unex-
pectedly fail or, in the case of an accident, no
longer withstand the strain they are designed
to.
If the underbody paneling is damaged, com-
bustible materials such as leaves, grass or twigs can gather between the underbody and
the underbody paneling. If these materials
come in contact with hot parts of the exhaust
system, they can catch fire.
In such situations, have the vehicle checked
and repaired immediately at a qualified spe-
cialist workshop. If on continuing your jour-
ney you notice that driving safety is impaired,
pull over and stop the vehicle immediately,
paying attention to road and traffic condi-
tions. In such cases, consult a qualified spe-
cialist workshop.
When driving off-road, substances such as sand,
mud and water or water mixed with oil may get
into the brakes. This could result in a reduced
braking effect or in total brake failure and also in
increased wear and tear. The braking charac-
teristics change depending on the material
ingressing the brakes. Clean the brakes after
driving off-road. If you detect a reduced braking
effect or grinding noises, have the brake system
checked in a qualified specialist workshop as
soon as possible. Adapt your driving style to the
different braking characteristics.
Driving off-road increases the likelihood of dam-
age to the vehicle, which, in turn, can lead to
failure of the mechanical assembly or syst ems.
A
dapt your driving style to suit the terrain con-
ditions. Drive carefully. Have damage to the
vehicle rectified immediately at a qualified spe-
cialist workshop.
Do not switch to transmission position N when
driving off-road. If you try to brake the vehicle
using the service brake, you could lose control
of the vehicle. If the gradient is too steep for your
vehicle, drive back down in reverse gear.
General notes Read this section carefully before driving your
vehicle off-road. Practice by driving over more
gentle off-road terrain first.
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: R
the Offroad drive program (vehicles without
Off-Road Engineering package)
( Y
page 217) R
Offroad and Offroad Plus drive programs
(vehicles with Off-Road Engineering package)
( Y
page 218)168
Driving tips
Driving and parking

R
LOW RANGE offroad gear (vehicles with the
Offroad Engineering package) ( Y
page 219)R
Differential lock (vehicles with the Off-Road
Engineering package) ( Y
page 218)R
Off-road ABS ( Y
page 64)R
Off-road 4ETS ( Y
page 67)R
Off-road ESP ®
( Y
page 68)R
AIRMATIC package (vehicle level)
( Y
page 186) R
DSR (Downhill Speed Regulation)
( Y
page 216)
Observe the following notes: R
Stop the vehicle before starting to drive along
an off-road route. If necessary, select the off-
road program ( Y
page 218) or shift to the
LOW RANGE off-road gear ( Y
page 219).R
Select a vehicle level that is suitable for the
terrain. To avoid damaging the vehicle, make
sure there is always sufficient ground clear-
ance. R
Check that items of luggage and loads are
stowed safely and are well secured
( Y
page 299). R
Always keep the engine running and in gear
when driving on a downhill gradient. Activate
DSR ( Y
page 216).R
Always keep the engine running and in gear
when driving on a slope. R
Adapt your speed to the terrain. The rougher,
steeper or more ruts on the terrain, the slower
your speed should be. R
Do not jump with the vehicle as this will inter-
rupt the vehicle's propulsion. R
Drive 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. R
Look out for obstacles, such as rocks, holes,
tree stumps and furrows. R
Always keep the doors, the tailgate, the side
windows and the sliding sunroof closed while
the vehicle is in motion. R
Do not shift the automatic transmission to
transmission position N .R
Observe the notes on off-road fording
( Y
page 167).
i Do 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. X
Engine 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. X
DEF tank (BlueTEC vehicles): check the
level and add if necessary ( Y
page 156).X
Tire-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. X
Wheels and tires: check the tire tread depth
and tire pressure. X
Check for damage and remove any foreign
objects, e.g. small stones, from the wheels/
tires. X
Replace any missing valve caps. X
Replace dented or damaged wheels. X
Rims: dented or bent rims can result in a loss
of tire pressure and damage the tire bead.
Before driving off-road, check the wheels and
replace them if necessary.
Checklist after driving off-road
! If you detect damage to the vehicle after
driving off-road, have the vehicle checked
immediately at a qualified specialist work-
shop.
Driving over rough terrain places greater
demands on your vehicle than driving on normal
roads. After driving off-road, check the vehicle.
This allows you to detect damage promptly and
reduce the risk of an accident to yourself and
other road users. X
If the Offroad or Offroad Plus drive program
is selected: select the Individual , Sport ,Driving tips 169
Driving and parking Z

Comfort or Slippery drive program
( Y
page 145).X
Deactivate the LOW RANGE off-road gear
( Y
page 219).X
Deactivate DSR ( Y
page 216).X
Lower the vehicle level again to a level suita-
ble to the road conditions, e.g. to the normal
level. X
Clean the headlamps and rear lights and
check for damage. X
Clean the front and rear license plates. X
Clean the wheels and tires with a water jet
and remove any foreign objects. X
Clean the wheels, wheel housings and the
vehicle underside with a water jet; check for
any foreign objects and damage. X
Check whether twigs or other parts of plants
have become trapped. These increase the risk
of fire and can damage fuel pipes, brake
hoses or the rubber bellows of the axle joints
and propeller shafts. X
After the trip, examine without fail the entire
undercarriage, wheels, tires, brakes, body-
work structure, steering, chassis and exhaust
system for damage. X
After driving for extended periods across
sand, mud, gravel, water or in similarly dirty
conditions, have the brake discs, wheels,
brake pads/linings and axle joints checked
and cleaned. X
If you detect strong vibrations after off-road
travel, check for foreign objects in the wheels
and drive train and remove them if necessary.
Foreign objects can disturb the balance and
cause vibrations.
Driving on sand Observe the following rules when driving on
sand: R
Select the Offroad drive program (vehicles
without Off-Road Engineering package)
( Y
page 217).R
Select the Offroad drive program (vehicles
with Off-Road Engineering package)
( Y
page 218).R
Select a higher vehicle level. R
Avoid high engine speeds. R
Use the left-hand steering wheel paddle
shifter to shift to a lower gear appropriate to
the terrain. R
Drive quickly to overcome the rolling resist-
ance. Otherwise the vehicle's wheels could
become stuck in loose ground. R
Drive in the tracks of other vehicles if possi-
ble. Make sure that: -
the tire ruts are not too deep. -
the sand is sufficiently firm. -
the ground clearance of the vehicle is suf-
ficient.
Tire ruts and gravel roads
! Check that the ruts are not too deep and
that your vehicle has sufficient clearance.
Otherwise, your vehicle could be damaged or
bottom out and get stuck.
Observe the following rules when driving along
ruts in off-road terrain or on roads with loose
gravel: R
Select the Offroad drive program (vehicles
without Off-Road Engineering package)
( Y
page 217). R
Select the Offroad drive program (vehicles
with Off-Road Engineering package)
( Y
page 218). R
Select a higher vehicle level. R
Avoid high engine speeds. R
Shift to a lower gear using the left-hand steer-
ing wheel paddle shifter. R
Drive slowly. R
Where ruts are too deep, drive with the
wheels of one side on the center grassy area,
if possible.
Driving over obstacles
! Obstacles could damage the floor of the
vehicle or components of the chassis. Ask
passengers for guidance when driving over
large obstacles. The passenger should always
keep a safe distance from the vehicle when
doing so in order to avoid injury as a result of
unexpected vehicle movements. After driving
off-road or over obstacles, check the vehicle
for possible damage, especially to the under-
body and the components of the chassis.170
Driving tips
Driving and parking

Problems with Parking Assist PARKTRONIC Problem
Possible causes/consequences and P Solutions
Only the red segments in
the Parking Assist
PARKTRONIC warning
displays are lit. You also
hear a warning tone for
approximately two sec-
onds.
Parking Assist
PARKTRONIC is deacti-
vated after approx-
imately five seconds,
and the indicator lamp in
the Parking Assist
PARKTRONIC button
lights up. Parking Assist PARKTRONIC has malfunctioned and has been deacti-
vated. X
If problems persist, have Parking Assist PARKTRONIC checked at a
qualified specialist workshop.
Only the red segments in
the Parking Assist
PARKTRONIC warning
displays are lit. Parking
Assist PARKTRONIC is
deactivated after
approximately five sec-
onds. The Parking Assist PARKTRONIC sensors are dirty or there is inter-
ference. X
Clean the Parking Assist PARKTRONIC sensors ( Y
page 328).X
Switch the ignition back on.
The problem may be caused by an external source of radio or ultra-
sound waves. X
Check to see if Parking Assist PARKTRONIC works at a different
location.
Parking Pilot
General notes Parking Pilot is an electronic parking aid with
ultrasound. It measures the road on both sides
of the vehicle. A parking symbol indicates a suit-
able parking space. Active steering intervention
and brake application can assist you during
parking. Parking Assist PARKTRONIC is also
available ( Y
page 190).
Important safety notes
Parking Pilot is only an aid. It is not a replace-
ment for your attention to your immediate sur-
roundings. You are always responsible for safe
maneuvering, parking and exiting a parking
space. Make sure that no persons, animals or
objects are in the maneuvering range.
When Parking Assist PARKTRONIC is deactiva-
ted, Parking Pilot is also unavailable. G WARNING
While parking or pulling out of a parking
space, the vehicle swings out and can drive
onto areas of the oncoming lane. This could
result in a collision with another road user.
There is a risk of an accident.
Pay attention to other road users. Stop the
vehicle if necessary or cancel the Active Park-
ing Assist parking procedure.
! If unavoidable, you should drive over obsta-
cles such as curbs slowly and not at a sharp
angle. Otherwise, you may damage the
wheels or tires.
Parking Pilot may show parking spaces which
are not suitable for parking, e.g.: R
where parking or stopping is prohibited R
in front of driveways or entrances and exits R
on unsuitable surfacesDriving systems 193
Driving and parking Z

! A function or performance test should only
be carried out on a two-axle dynamometer.
Before you operate the vehicle on such a
dynamometer, please consult a qualified
workshop. You could otherwise damage the
drive train or the brake system.
i In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if you
use winter tires (M+S tires), with snow chains
if necessary.
Further information about "Driving off-road"
( Y
page 168).
DSR (Downhill Speed Regulation) General notes DSR is an aid to assist you when driving down-
hill. It keeps the speed of travel at the speed
selected on the on-board computer. The steeper
the downhill gradient, the greater the DSR brak-
ing effect on the vehicle. When driving on flat
stretches of road or on an uphill gradient, the
DSR braking effect is minimal or nonexistent.
DSR controls the vehicle’s speed when it is acti-
vated and the transmission is in position D , R or
N . You can drive at a higher or a lower speed
than that set on the on-board computer at any
time by accelerating or braking.
Important safety notes
G WARNING
If the speed driven and the set speed deviate
and you activate DSR on a slippery road sur-
face, the wheels may lose traction. There is an
increased danger of skidding and accidents.
Before switching DSR on, please take into
consideration the road surface and the differ-
ence between driving speed and the set
speed.
If you fail to adapt your driving style, DSR can
neither reduce the risk of accident nor override
the laws of physics. DSR cannot take account of
road, weather and traffic conditions. DSR is only
an aid. You are responsible for the distance to
the vehicle in front, for vehicle speed, for brak-
ing in good time and for staying in your lane.
You are always responsible for keeping control
of the vehicle and for assessing whether the
downhill gradient can be managed. DSR may not
always be able to keep to the set speed, depend- ing on road surface and tire conditions. Select a
set speed suitable for the prevailing conditions
and when necessary, apply the brakes manually.
Activating DSR X
Press button C .
Indicator lamp D lights up.
The