brakes MERCEDES-BENZ M-Class 2014 W166 User Guide

these exhaust gases leads to poisoning. There
is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces
withou tsufficient ventilation.
Certain engine systems are designed to keep
the level of poisonous components in exhaust
fumes within legal limits.
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 th eengine must be carried
ou tb y qualified and authorized Mercedes-
Benz technicians.
The engine settings mus tnot 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 gives you information on how
economical your driving style is. The ECO
display assists you in achieving the optimum
driving style in terms of consumption, taking
the actual and selected conditions into
consideration. Your driving style can
significantly influence the vehicle's
consumption.
The ECO display consists of three bars:
R Acceleration R
Constant R
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%. Ahigher percentage indicates a mor
eeconomical
driving style.
The ECO display does not indicate the actual
fuel consumption and a fixed percentage
count in the ECO display does not indicate a
fixed consumption figure.
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 taken into
consideration by the ECO display.
The evaluation of your driving style is carried
ou tu sing the following three categories:
R Acceleration (evaluation of all
acceleration processes):
- The bar fills up: moderate acceleration,
especially at higher speeds
- The bar empties: sporty acceleration
R Constant (assessment of driving behavior
at all times):
- The bar fills up: constant speed and
avoidance of unnecessary acceleration
and deceleration
- The bar empties: fluctuations in speed
R Coasting (assessment of all deceleration
processes):
- The bar fills up: anticipatory driving,
keeping your distance and early release
of the accelerator. The vehicle can coast
without use of the brakes.
- The bar empties: frequent braking
i An economical driving style specially
requires driving at moderate engine
speeds.
To achieve a higher value in the categories
Acceleration and
Constant , observe the
gearshift recommendations. Driving tips
183Driving and parking Z

i
On long journeys at a constant speed, e.g.
on the highway, only the bar for Constantwill change.
i The ECO display summaries the driving
characteristics from the start of the journey
to its completion. For this reason, the bars
change dynamically at the beginning of the
journey. On longer journeys, there are
fewer changes. For more dynamic changes,
carry out a manual reset.
Further information on the ECO display
(Y page 267). 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
braking 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
surface. This could cause damage to the
drive train. This type of damage is not
covered by the Mercedes-Benz warranty.
Do not depress the brake pedal continuously
while the vehicle is in motion, e.g. causing the
brakes to rub by constantly applying light
pressure to the pedal.T his results in
excessive 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.N ever
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
reaction 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
residue may form on the brake discs and
brake pads. This can result in a significantly
longer braking distance.184
Driving tipsDriving and parking

R
Brake occasionally to remove any possible
salt residue. Make sure that you do not
endanger othe rroad users when doing so.
R Carefully depress the brake pedal and the
beginning and end of a journey.
R Maintain a greater distance to the vehicle
ahead.
Servicing the brakes !
If the red brake warning lamp lights up in
the instrument cluster and you hear a
warning tone while the engine is running,
the brake fluid level may be too low.
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. This work should be carried
out at a qualified specialist workshop.
! A function or performance test should
only be carried out on a2-axle
dynamometer. 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
electri cparking brake is being tested on a
brake dynamomete r(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 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
functionality of your brakes at regular
intervals. To do so, press firmly on the brake
pedal 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 67) or of BAS PLUS on
(Y page 68).
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 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
installed only on the ML 63 AMG.
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
temperature 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
mileage that will be valid under all
circumstances. An aggressive driving style Driving tips
185Driving and parking Z

will lead to high wear. You can obtain further
informatio
nabout 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
correspondingly high brake wear. Observe
the 0009 brake wear warning lamp in the
instrument cluster and note any brake status
messages in the multifunction display.
Especially for high performance 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
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 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
components in the engin eorthe 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:
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
equipment.
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 454). 186
Driving tipsDriving and parking

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 arisk of an
accident.
Selec tthe 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
characteristics change depending on the
material ingressing the brakes. Cleant he
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
damage to the vehicle, which, in turn, can lead
to failure of the mechanical assembly or
systems. Adapt your driving style to suit the
terrain conditions. Drive carefully. Have
damage to the vehicle rectified immediately
at a qualified specialist workshop.
Do not switch to transmission position N
when driving off-road. You could lose control
of the vehicle if you attempt to brake using
the service brake. If the gradient is too steep,
drive backwards 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
Off-road ABS (Y page 67)
R AIRMATIC package (vehicle level)
(Y page 207)
R DSR (Downhill Speed Regulation)
(Y page 246)
Observe the following notes:
R Stop the vehicle before starting to drive
along an off-road route.
R For vehicles with the AIRMATIC
package: select a vehicle level that is
suitable for the off-road terrain. To avoid
damaging the vehicle, make sure there is
always sufficient ground clearance.
R Check that items of luggage and loads are
stowed safely and are well secured
(Y page 337).
R Always keep the engine running and in gear
when driving on a downhill gradient.
Activate DSR (Y page 246).
R Always keep the doors, tailgate, windows
and sliding sunroof closed while driving.
R Adapt your speed to the terrain. The
rougher, steeper or more ruts on the
terrain, the slower your speed should be.
R Drive slowly and at an even speed through
the water. Ensure that a bow wave does not
form as you drive.
R Drive with extreme care on unfamiliar off-
road routes where visibility is poor. For
safety reasons, 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 Check the depth of water before fording
rivers and streams.
R When fording, do not stop and do not
switch off the engine.
R On sand, drive quickly to overcome the
rolling resistance. Otherwise the vehicle's
wheels could become stuck in loose
ground. 188
Driving tipsDriving and parking

R
Do not jump with the vehicle as this will
interrupt the vehicle's propulsion.
R Always keep the engine running and in gear
when driving on a slope.
R Do not shift the automatic transmission to
transmission position N.
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 functio ncannot hold the vehicle
on such surfaces.
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.
Chec kthe 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 177).
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
workshop.
X Deactivate DSR (Y page 246).
X Vehicles with the AIRMATIC package:
lower the vehicle to a ride height suitable
for the road conditions, e.g. to the
highway/high-speed level.
X Cleant he headlamps and rear lights and
check for damage.
X Cleant he front and rear license plates.
X Cleant he wheels/tires with a water jet and
remove any foreign objects.
X Cleant he 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,
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
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. Driving tips
189Driving and parking Z

angle of 45°. Note that the climbing ability
of your vehicle depends on the terrain
conditions.
R When driving down an incline, make use of
the engine's braking effect. Observe the
engine speed; do no toverrev the engine.
R Drive slowly.
R Avoid high engine speeds. Drive at
appropriate engine speeds (maximum
3,000 rpm).
R Use the left-hand paddle shifter to shift into
a lower gearing ood time on long and steep
downhill gradients.
R Check the brakes after prolonged off-road
driving.
i Hill start assist will aid you when pulling
away on a hill.
For further information about hill start
assist, see (Y page 161).
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.
Always observe the approach/departure
angle values (Y page 454).
Maximu mgradient-climbing capability Always observe the maximum gradient
climbing ability values (Y page 455).
Hilltops When driving up an uphill gradient, slightly
reduce pressure on the accelerator
immediately before reaching the brow of the
hill .Use the vehicle's own impetus to drive
over the top of the hill.
This style of driving prevents:
R the vehicle from lifting off the ground on the
brow of a hill
R the vehicle from traveling too quickly down
the other side Driving downhill R
Drive slowly.
R Do 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.
R Shift to a lower gear using the left-hand
paddle shifter before tackling steep
downhill gradients.
R Activate 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.
R Check that the brakes are working normally
after a long downhill stretch.
i The 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
completely braked and therefore lose their
ability to steer. Driving systems
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 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
system and prevents the brakes from
overheating and wearing too quickly.
Use cruise control only if road and traffic
conditions make it appropriate to maintain a
steady speed for a prolonged period. You can
store any road speed above 20 mph
(30 km/h). Driving systems
191Driving and parking Z

stored speed is resumed when the gradient
evens out. Cruise control maintains the
stored speed on downhill gradients by
automatically applying the brakes.
Storing or calling up aspeed G
WARNING
If you call up the stored speed and it differs
from the current speed, the vehicle
accelerates or decelerates. If you do not know
the stored speed, the vehicle could accelerate
or brake unexpectedly. There is a ris kofan
accident.
Pay attention to the road and traffic
conditions before calling up the stored speed.
If you do no tknow the stored speed, store the
desired speed again. X
Briefly pull the cruise control lever towards
you 0002.
X Remove your foo tfrom the accelerator
pedal.
The first time cruise control is activated, it
stores the current speed or regulates the
speed of the vehicle to the previously
stored speed. Setting
aspeed Keep in mind tha
titmay take a brie fmoment
until the vehicle has accelerated or braked to
the speed set.
X Press the cruise control lever up 0002for a
higher speed or down 0003for a lower speed.
X To adjust the set speed in 1 mph
increments (1 km/h increments): briefly
press the cruise control lever up 0002or
down 0003to the pressure point.
Every time the cruise control lever is
pressed up 0002or down 0003the last speed
stored is increased or reduced.
X To adjust the set speed in 5 mph
increments (10 km/h increments):
briefly press the cruise control lever
up 0002 or down 0003to the pressure point.
Every time the cruise control lever is
pressed up 0002or down 0003the last speed
stored is increased or reduced.
i Cruise control is not deactivated if you
depress the accelerator pedal. For
example, if you accelerate briefly to
overtake, cruise control adjusts the
vehicle's speed to the last speed stored
after you have finished overtaking. Driving systems
193Driving and parking Z

Deactivating cruise control
There are several ways to deactivate cruise
control:
X
Briefly press the cruise control lever
forwards 0002.
or
X Brake.
Cruise control is automatically deactivated if:
R you engage the electric parking brake.
R you are driving at less than 20 mph
(30 km/h).
R ESP ®
intervenes or you deactivate ESP ®
.
R you activate DSR.
R you shift the transmissio nto position N
while driving.
If cruise control is deactivated, you will hear
a warning tone. You will see the CruiseControl Off message in the multifunction
display for approximately five seconds.
i When you switch off the engine, the last
speed stored is cleared. DISTRONIC PLUS
General notes DISTRONIC PLUS regulates the speed and
automatically helps you maintain the
distance to the vehicle detected in front.
DISTRONIC PLUS brakes automatically 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 system and prevents the brakes
from overheating and wearing too quickly.
If DISTRONIC PLUS detects a slower-moving
vehicle in front, your vehicle is braked in order
to maintain the preset distance to the vehicle
in front.
If DISTRONIC PLUS detects that there is a risk
of a collision, you will be warned visually and
acoustically. DISTRONIC PLUS cannot
prevent a collision without your intervention.
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 DISTRONIC PLUS to assist you when
driving, the radar sensor system must be:
R activated(Y page 276)
R operational
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control in the speed range between 20 mph
(Canada: 30 km/h) and 120 mph (Canada:
200 km/h). If a vehicle is driving in front of
you, it operates in the speed range between
0 mph (0 km/h) and 120 mph (Canada:
200 km/h).
Do not use DISTRONIC PLUS while driving on
roads with steep gradients.
As DISTRONIC PLUS 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.
i USA only:
This device has been approved by the FCC
as a "Vehicular RadarS ystem". The radar
sensor is intended fo ruse in an automotive
radar system only. Removing, tampering
with, or altering the device will void any
warranties, and is not permitted by the 194
Driving systemsDriving and parking

FCC
.Do not tamper 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.
i Canada 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
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the
device will void any warranties, and is not
permitted. Do not tamper 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.
Important safety notes G
WARNING
DISTRONIC PLUS does not react to:
R people or animals
R stationary obstacles on the road, e.g.
stopped or parked vehicles
R oncoming and crossin gtraffic
As a result, DISTRONIC PLUS may neither give
warnings nor intervene in such situations.
There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake. G
WARNING
DISTRONIC PLUS cannot always clearly
identify other road users and comple xtraffic
situations.
In such cases, DISTRONIC PLUS may:
R give an unnecessary warning and then
brake the vehicle
R neither give a warning nor intervene
R accelerate unexpectedly There is a risk of an accident.
Continue to drive carefully and be ready to
brake, in particular when warned to do so by
DISTRONIC PLUS.
G
WARNING
DISTRONIC PLUS brakes yourv ehicle with up
to 40% of the maximum braking force. If this
braking force is insufficient, DISTRONIC PLUS
warns you visually and audibly .There is a risk
of an accident.
In such cases, apply the brakes yourself and
try to take evasive action.
! If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes
automatically in certain situations. To
prevent damage to the vehicle, deactivate
DISTRONIC PLUS and the HOLD function in
the following or other similar situations:
R when towing the vehicle
R in the car wash
If you fail to adapt your driving style,
DISTRONIC PLUS can neither reduce the risk
of accident nor override the laws of physics.
DISTRONIC PLUS cannot take into account
the road, traffic and weather conditions.
DISTRONIC PLUS 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 DISTRONIC PLUS:
R in road and traffic conditions which do not
allow you to maintain a constant speed e.g.
in heavy traffic or on winding roads
R on slippery road surfaces. Braking or
accelerating could cause the drive wheels
to lose traction and the vehicle could then
skid
R when there is poor visibility, e.g. due to fog,
heavy rain or snow
DISTRONIC PLUS may not detect narrow
vehicles driving in front, e.g. motorcycles, or
vehicles driving on a different line. Driving systems
195Driving and parking Z