2015 MERCEDES-BENZ GL-Class brakes

the brake system checked at a qualified spe-
cialist workshop.
Observe information regarding indicator and
warning lamps (Y page 329) as well as dis-
play messages (Y page 295).ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In addi-
tion to the braking function, ADAPTIVE BRAKE
also has the HOLD function (Y page 218)and
hill start assist (Y page 171). PRE-SAFE
®
Brake
General information i
Observe the "Important safety notes" sec-
tion (Y page 68).
PRE-SAFE ®
Brake is only available in vehicles
with DISTRONIC PLUS.
For PRE-SAFE ®
Brake to assist you when driv-
ing, the radar sensor system must be opera-
tional.
With the help of the radar sensor system,
PRE-SAFE ®
Brake can detect obstacles that
are in front of your vehicle for an extended
period of time.
PRE-SAFE ®
Brake can help you to minimize
the risk of a collision with a vehicle ahead, and reduce the effects of such a collision. If PRE-
SAFE ®
Brake has detected a risk of collision,
you will be warned visually and acoustically as
well as by automatic braking. PRE-SAFE ®
Brake cannot prevent a collision without your intervention.
Important safety notes G
WARNING
PRE-SAFE ®
Brake will initially brake your vehi-
cle by a partial application of the brakes if a
danger of collision is detected. There may be a collision unless you also brake. Automatic
emergency braking cannot prevent a colli-
sion. There is a risk of an accident.
Always apply the brakes yourself and try to
take evasive action. G
WARNING
PRE-SAFE ®
Brake cannot always clearly iden-
tify objects and complex traffic conditions.
In these cases, PRE-SAFE ®
Brake may:
R give an unnecessary warning and then
brake the vehicle
R not give a warning or intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and be ready to brake, especially if
PRE-SAFE ®
Brake warns you. Terminate the
intervention in a non-critical driving situation.
In order to maintain the appropriate distance
to the vehicle in front and thus prevent a col- lision, you must apply the brakes yourself. G
WARNING
PRE-SAFE ®
Brake does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
As a result, PRE-SAFE ®
Brake may neither
give warnings nor intervene in all critical sit-
uations. There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
In the event of snowfall or heavy rain, the rec-
ognition can be impaired.
Recognition by the radar sensor system is
also impaired in the event of:
R dirt on the sensors or anything else cover-
ing the sensors
R interference by other radar sources
R strong radar reflections, for example in
parking garages 76
Driving safety systemsSafety

General notes
0043
ECO start/stop display
If the 00A7 symbol is shown in green in the
multifunction display, the ECO start/stop
function switches the engine off automati-
cally if the vehicle stops moving.
Every time you switch on the engine using the
SmartKey or the Start/Stop button, the ECO
start/stop function is activated.
If the ECO start/stop function has been man- ually deactivated (Y page 173) or a malfunc-
tion has caused the system to be deactivated, the 00A7 symbol is not displayed.
AMG vehicles: the ECO start/stop function
is only available in drive program C.
For further information on automatic engine
switch-off (Y page 172) and automatic
engine start (Y page 172).
Automatic engine switch-off If the vehicle is braked to a standstill in
Dor N,
the ECO start/stop function switches off the engine automatically.
The ECO start/stop function is operational
and the 00A7symbol is displayed in green in
the multifunction display, if:
R the indicator lamp in the ECO button is lit
green.
R no off-road program has been selected.
R the outside temperature is within the range
that is suitable for the system.
R the engine is at normal operating temper-
ature.
R the set temperature for the vehicle interior
has been reached.
R the battery is sufficiently charged. R
the system detects that the windshield is
not fogged up when the air-conditioning
system is switched on.
R the hood is closed.
R the driver's door is closed and the driver's
seat belt is fastened.
If conditions for automatic engine switch-off
have not been fulfilled, the 00A7symbol will
be shown in yellow.
i All of the vehicle's systems remain active
when the engine has been stopped auto-
matically.
i The HOLD function can be activated if the
engine has been switched off automati-
cally. It is then not necessary to continue
applying the brakes during the automatic
stop phase. When you depress the accel-
erator pedal, the engine starts automati-
cally and the braking effect of the HOLD
function is deactivated.
i All vehicles (apart from AMG vehicles):
automatic engine switch-off can take place a maximum of four times consecutively (ini-
tial stop then repeated three times). The
00A7 symbol is shown in yellow in the mul-
tifunction display after the engine has been started automatically for the fourth time.
When the 00A7symbol is shown in green in
the multifunction display, automatic engine switch-off is again possible.
i AMG vehicles:
times which the engine
can be automatically switched off.
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 Dor Nthe brake
pedal is released and the HOLD function is not active.
R you depress the accelerator pedal.
R you engage reverse gear R.172
DrivingDriving and parking

These systems only work at peak efficiency if
they are serviced exactly in accordance with
the manufacturer's specifications. For this
reason, all work on the engine must be carried out by qualified and authorized Mercedes-
Benz technicians.
The engine settings must not be changed
under any circumstances. Furthermore, all
specific service work must be carried out at
regular intervals and in accordance with the
Mercedes-Benz service requirements. Details
can be found in the Maintenance Booklet. ECO display
Example: ECO display
The ECO display provides feedback on how
economical your driving characteristics are.
The ECO display assists you in achieving the
most economical driving style for the selec-
ted settings and prevailing conditions. Your
driving style can significantly influence the
vehicle's consumption.
The ECO display consists of three bars:
R Acceleration
Acceleration
R Constant Constant
R Coasting
Coasting
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 Acceleration
Acceleration (evaluation of all accelera-
tion processes):
- The bar fills up: moderate acceleration,
especially at higher speeds
- The bar empties: sporty acceleration
R Constant 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 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
Acceleration
Acceleration andConstant Constant, observe the
gearshift recommendations.
i On long journeys at a constant speed, e.g.
on the highway, only the bar for Constant
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 Driving tips
195Driving and parking Z

fewer changes. For more dynamic changes,
carry out a manual reset.
For further information on the ECO display,
see (Y page 278). 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 bythe 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.
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. 196
Driving tipsDriving and parking

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 0or 1or Start/
Stop button in position 0or 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.
If the brake system has only been subject to
moderate loads, you should test the function- ality of your brakes at regular intervals. To doso, depress the brake pedal firmly when driv-
ing at a high speed. This improves the grip of
the brake pads.
You can find a description of Brake Assist
(BAS) on (Y page 69) 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 vehi-
cle'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 corresponds 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 for
AMG vehicles The high-performance brake system is only
available on 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 temper-
ature and humidity
The wear of individual components of the
brake system, such as the brake pads/linings
or brake discs, depends on the individual driv-
ing style and operating conditions.
For this reason, it is impossible to state a
mileage that will be valid under all circum-
stances. An aggressive driving style will lead
to high wear. You can obtain further informa- tion about this from your authorized
Mercedes-Benz Center.
New and replaced brake pads and discs only
reach their optimum braking effect after sev-
eral hundred kilometers of driving. Compen-
sate for this by applying greater force to the
brake pedal. Keep this in mind, and adapt Driving tips
197Driving and parking Z

your driving and braking accordingly during
this break-in period.
Excessive heavy braking results in corre-
spondingly high brake wear. Observe the
0026 brake wear warning lamp in the instru-
ment cluster and note any brake status mes-
sages in the multifunction display. Especially
for high performance driving, it is important to maintain and have the brake system checkedregularly. Driving on wet roads
Hydroplaning If water has accumulated to a certain depth
on the road surface, there is a danger of
hydroplaning 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. Otherwise, water may enter the
vehicle interior or the engine compartment.
This can damage the electronic compo-
nents in the engine or the automatic trans- mission. 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:
set the raised level before driving through
standing water. Off-road fording !
Under no circumstances should you
accelerate 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 equip-
ment.
R Establish how deep the water is and the
characteristics of the body of water before
fording.
R Vehicles with the AIRMATIC package:
select the highest possible vehicle level.
R Shift to a lower gear using the left-hand
steering 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 Do not stop.
R Water offers a high degree of resistance,
and the ground is slippery and in some
cases unstable. Therefore, it is difficult and
dangerous to pull away in the water.
R Ensure that a bow wave does not form as
you drive.
R Clean any mud from the tire tread after
fording.
R Apply the brakes to dry them after fording.
Always observe the fording depth values
(Y page 456). 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. 198
Driving tipsDriving and pa
rking

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 quali-
fied specialist workshop at the onset of win-
ter.
Drive particularly carefully on slippery road
surfaces. Avoid sudden acceleration, steering and braking maneuvers. Do not use the cruise
control or DISTRONIC PLUS.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X Shift the transmission to position N.
Vehicles with the ON&OFFROAD package:
if driving in snow or with snow chains, select
the snow program (Y page 256) with the off-
road program selector wheel in the center
console.
i Vehicles with a diesel engine:
do not
cover the radiator, e.g. with a protective
cover. The measuring function of the
onboard diagnosis system may otherwise
provide inaccurate values. Some of these
values are required by law and must there-
fore 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 freez-
ing point do not guarantee that the road sur-
face is free of ice. The road may still be icy,
especially in wooded areas or on bridges. You
should pay special attention to road condi-
tions when temperatures are around the
freezing point.
For more information on driving with snow
chains, see (Y page 409).
For more information on driving with summer
tires, see (Y page 408).
Observe the notes in the "Winter operation"
section (Y page 408). 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
If the vehicle level is high, the vehicle center of gravity is raised. This could cause the vehicleto tip over more easily on uphill or downhill
gradients. There is a risk of an accident.
Select the lowest possible vehicle level.
When driving off-road, sand, mud and water,
possibly mixed with oil, for example, could 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 char- acteristics change depending on the materialingressing the brakes. Clean the brakes after
driving off-road. If you detect a reduced brak- ing effect or grinding noises, have the brake
system checked in a qualified specialist work-shop as soon as possible. Adapt your driving
style to the different braking characteristics. Driving
tips
199Driving an d parking Z

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 top up if necessary (Y page 188).
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. Therefore, check your rims before
driving off-road and replace them as
required.
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.
X Vehicles with the ON&OFFROAD pack-
age: activate the on-road program
(Y page 259).
X Deactivate the LOW RANGE off-road gear
(Y page 261).
X Deactivate DSR (Y page 258).
X Vehicles with the AIRMATIC package:
lower the vehicle to a ride height suitable
for the road conditions, e.g. to the high-
way/high-speed level. X
Clean the headlamps and rear lights and
check for damage.
X Clean the front and rear license plates.
X Clean the wheels/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 bel-
lows of the axle joints and propeller shafts.
X After the trip, examine without fail the
entire undercarriage, wheels, tires, brakes,
bodywork 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 over rough terrain places greater
demands on your vehicle than driving on nor-
mal 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.
Driving on sand Observe the following rules when driving on
sand:
R Vehicles with the ON&OFFROAD pack-
age: select off-road program 1
(Y page 259).
R Vehicles with the AIRMATIC package:
select a raised vehicle level.
R Avoid high engine speeds. Driving tips
201Driving and pa rking Z