brakes MERCEDES-BENZ GLA-Class 2015 X156 User Guide

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 firsttime. This may also occur after the vehicle has
been washed or driven through deep water.
You 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.
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 tobrake 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.
! As the ESP ®
system operates automati-
cally, the engine and the ignition must be
switched off (the SmartKey must be in posi-
tion 0or 1in the ignition lock) if:
R the electric parking brake is tested on a
brake dynamometer (for a maximum of
ten seconds)
R the vehicle is towed with the front axle
raised.
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. Driving tips
165Driving and parking Z

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.
You can find a description of Brake Assist
(BAS) on (Y page 65).
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.
Checking brake lining thickness You can measure the break pad/lining thick-
ness using a test gauge. Color-coding (green
or red) on the test gauge allows you to deter-
mine whether the brake pad/lining thickness is still sufficient. The test gauge is in the vehi-
cle document wallet in the glove box. Front wheel
Rear wheel
X Bring the vehicle and wheels into a suitable
position so that you can attach test gauge
0083.
X Secure the vehicle against rolling away
(Y page 159).
X Move the selector lever to position P.
X Switch off the engine.
X Place test gauge 0083between the wheel's
spokes on brake pad/lining 0087.166
Driving tipsDriving and parking

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 con-
ditions when temperatures are around freez-
ing point.
For more information on driving with snow
chains, see (Y page 327).
For more information on driving with summer tires, see (Y page 326).
Observe the notes in the "Winter operation"
section (Y page 326). 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. !
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 or a hole in the road
R a heavy object strikes the undercarriage
or parts of the chassis
In situations like this, the body, the under-
carriage, chassis parts, wheels or tires
could be damaged without the damage
being visible. Components damaged in this
way can unexpectedly fail or, in the case of
an accident, no longer withstand the strain
they are designed to.
If the underbody paneling is damaged,
combustible 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 specialist workshop. If on con-
tinuing your journey you notice that driving
safety is impaired, pull over and stop the
vehicle immediately, paying attention to
road and traffic conditions. In such cases,
visit a qualified specialist workshop.
The vehicle is only designed for easily nego-
tiable off-road terrain and poor road surfaces.
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 brak- ing characteristics 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 brak- ing characteristics.
Driving off-road increases the likelihood of
damage to the vehicle, which, in turn, can lead 168
Driving tipsDriving and parking

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 Deactivate off-road program (Y page 186).
X Deactivate DSR (Y page 184).
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 in sand, mud, gravel, water or
similar dirty conditions, have the following
checked and cleaned:
R brake discs
R the wheels
R brake pads
R axle joints
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 poor road surfaces places
greater demands on your vehicle than driving on normal roads. After driving off-road, checkthe 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 Select the off-road program (Y page 186).
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 pos-
sible. Make sure that:
- the tire ruts are not too deep.
- the sand is sufficiently firm.
- the ground clearance of the vehicle is
sufficient.
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 Activate the off-road program
(Y page 186).
R Avoid high engine speeds.
R Shift to a lower gear using the left-hand
steering 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. Traveling uphill
Approach/departure angle G
WARNING
If you drive on a steep incline at an angle or
turn when driving on an incline, the vehicle 170
Driving tipsDriving and parking

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.
R Observe the warnings for off-road driving
(Y page 168).
R Follow the line of fall when driving on slopes
and steep inclines.
R Before driving on extreme uphill and down-
hill gradients, select the off-road program
(Y page 186).
R Drive slowly.
R Accelerate gently and make sure that the
wheels are gripping.
R Avoid high engine speeds, except when
driving on sandy and muddy routes with
high driving resistance.
R Use the left-hand steering wheel paddle
shifter to shift to a lower gear appropriate
to the gradient.
R Use the left-hand paddle shifter to shift into
a lower gear in good time on long and steep
downhill gradients.
i Hill start assist will aid you when pulling
away on a hill.
For further information about hill start
assist, see (Y page 144).
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 369).
Maximum gradient-climbing capability Always observe the maximum gradient climb-
ing ability values (Y page 369). Hilltops When driving up an uphill gradient, slightly
reduce pressure on the accelerator immedi-
ately 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:
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. Oth- erwise, the vehicle could slip sideways, tip
and rollover.
R Shift to a lower gear using the left-hand
paddle shifter before tackling steep down-
hill 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 Off-road ABS is activated when the off-
road program is selected.
At speeds below 18 mph (30 km/h), the
front wheels lock cyclically during braking.
The digging-in effect achieved in the proc-
ess reduces the stopping distance on off-
road terrain. The steerability of the vehicle
is considerably reduced if the wheels lock. Driving tips
171Driving and parking Z

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. On long and
steep downhill gradients, especially if the
vehicle is laden, you must select a low gear in
good time. For this, you will need to have
selected manual drive program M
(Y page 154). 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 canstore any road speed above 20 mph
(30 km/h).
Important safety notes If you fail to adapt your driving style, cruise
control can neither reduce the risk of an acci-
dent 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 dis-
tance to the vehicle in front, for vehicle speed, for braking in good time and for staying in
your lane.
Do not use cruise control:
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 accel-
erating 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
If there is a change of drivers, advise the new
driver of the speed stored. Cruise control lever
0043
To activate or increase speed
0044 To activate or reduce speed
0087 To deactivate cruise control
0085 To activate 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:
R the electric parking brake must be
released.
R you are driving faster than 20 mph
(30 km/h).
R ESP ®
must be active, but not intervening.
R on vehicles with automatic transmission,
the selector lever must be in position D.
Storing, maintaining and calling up a
speed Storing and maintaining the current
speed
You can store the current speed if you are
driving faster than 20 mph (30 km/h).172
Driving syste
msDriving and parking

X
Accelerate the vehicle to the desired
speed.
X Briefly press the cruise control lever up 0043
or down 0044.
X Remove your foot from the accelerator
pedal.
Cruise control is activated. The vehicle
automatically maintains the stored speed.
i Cruise 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
automatically applying the brakes.
Storing the current speed or calling up the
last stored speed G
WARNING
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.
X Briefly pull the cruise control lever towards
you 0085.
X Remove your foot from 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 a speed Keep in mind that it may take a brief moment
until the vehicle has accelerated or braked to the speed set. X
Press the cruise control lever up 0043for a
higher speed or down 0044for a lower speed.
X To adjust the set speed in 1 mph incre-
ments (1 km/h increments): briefly
press the cruise control lever up 0043or
down 0044to the pressure point.
Every time the cruise control lever is
pressed up 0043or down 0044the last speed
stored is increased or reduced.
X To adjust the set speed in 5 mph incre-
ments (10 km/h increments): briefly
press the cruise control lever up 0043or
down 0044to the pressure point.
Every time the cruise control lever is
pressed up 0043or down 0044the last speed
stored is increased or reduced.
i Cruise control is not deactivated if you
depress the accelerator pedal. For exam-
ple, if you accelerate briefly to overtake,
cruise control adjusts the vehicle's speed
to the last speed stored after you have fin- ished overtaking.
Deactivating cruise control There are several ways to deactivate cruise
control:
X Briefly press the cruise control lever for-
wards 0087.
or
X Brake.
Cruise control is automatically deactivated if: R the vehicle is secured with 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 shift the transmission to position N
while driving
If cruise control is deactivated, you will hear a warning tone. You will see the Cruise Con‐
Cruise Con‐
trol Off trol Off message in the multifunction dis-
play for approximately five seconds. Driving systems
173Driving and parking Z

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 dis-
tance to the vehicle detected in front. Vehi-
cles are detected with the aid of the radar
sensor system. DISTRONIC PLUS brakes
automatically so that the set speed is not
exceeded.
Change into a lower gear in good time on long
and steep downhill gradients. This is espe-
cially important if the vehicle is laden. 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 that there is a risk of a collision, you will be warned visually and
acoustically. DISTRONIC PLUS cannot pre-
vent 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.
DISTRONIC PLUS operates in range between0 mph (0 km/h) and 120 mph (200 km/h).
Do not use DISTRONIC PLUS while driving onroads 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 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.
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. stop-
ped or parked vehicles
R oncoming and crossing traffic
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 sit- uation and be ready to brake. G
WARNING
DISTRONIC PLUS cannot always clearly iden- tify other road users and complex traffic sit-
uations.
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 or brake 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 your vehicle with up to 50% of the maximum possible deceleration.
If this braking force is insufficient, DISTRONIC 174
Driving systemsDriving and parking

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 automati-
cally in certain situations. To prevent dam- age to the vehicle, deactivate DISTRONIC
PLUS and the HOLD function in the follow-
ing or other similar situations:
R when towing the vehicle
R in the car wash
If you fail to adapt your driving style, DIS-
TRONIC 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. DIS-
TRONIC PLUS is only an aid. You are respon- sible 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 accel-
erating 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.
In particular, the detection of obstacles can
be impaired if:
R there is dirt on the sensors or anything else
covering the sensors
R there is snow or heavy rain
R there is interference by other radar sources
R there are strong radar reflections, for
example, in parking garages
If DISTRONIC PLUS no longer detects a vehi- cle in front, DISTRONIC PLUS may unexpect- edly accelerate the vehicle to the stored
speed.
This speed may:
R be too high if you are driving in a filter lane
or an exit lane
R be so high when driving in the right-hand
lane that you overtake vehicles in the left-
hand lane
R be 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.
Cruise control lever 0043
To store the current speed or a higher
speed
0044 To store the current speed or a lower
speed
0087 To deactivate DISTRONIC PLUS
0085 To store the current speed or call up the
last stored speed
0083 To set the specified minimum distance
Activating DISTRONIC PLUS Activation conditions
To activate DISTRONIC PLUS, all of the fol-
lowing activation conditions must be fulfilled:
R the engine must be started. It may take up
to two minutes after pulling away before
DISTRONIC PLUS is operational.
R the electric parking brake must be
released. Driving systems
175Driving and parking Z

R
ESP ®
must be active, but not intervening.
R Active Parking Assist must not be activa-
ted.
R DSR must be deactivated.
R the transmission must be in position D.
R the driver's door must be closed when you
shift from Pto Dor your seat belt must be
fastened.
R the front-passenger door and rear doors
must be closed.
Activating
X Briefly pull the cruise control lever towards
you 0085or press it up 0043or down 0044.
DISTRONIC PLUS is selected.
X Press the cruise control lever repeatedly
up 0043 or down 0044until the desired speed is
set.
X Remove your foot from the accelerator
pedal.
Your vehicle adapts its speed to that of the
vehicle in front, but only up to the desired
stored speed.
i If you do not fully release the accelerator
pedal, the DISTRONIC
DISTRONIC PLUS PLUSPassive
Passive mes-
sage appears in the multifunction display.
The set distance to a slower-moving vehicle in front will then not be maintained. You will
be driving at the speed you determine by
the position of the accelerator pedal.
You can also activate DISTRONIC PLUS when
stationary. The lowest speed that can be set is
18 mph (30 km/h).
X Briefly pull the cruise control lever towards
you 0085or press it up 0043or down 0044.
DISTRONIC PLUS is selected.
Activating at the current speed/last
stored speed G
WARNING
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.
X Briefly pull the cruise control lever
(Y page 175) towards you 0085.
X Remove your foot from the accelerator
pedal.
DISTRONIC PLUS is activated. The first
time it is activated, the current speed is
stored. Otherwise, it sets the vehicle cruise
speed to the previously stored value.
Driving with DISTRONIC PLUS Pulling away and driving
i The vehicle can also pull away when it is
facing an unidentified obstacle or is driving
on a different line from another vehicle. The vehicle then brakes automatically. There is
a risk of an accident. Be ready to brake at all
times.
If you depress the brake, DISTRONIC PLUS is
deactivated unless your vehicle is stationary.
X If you want to pull away with DIS-
TRONIC PLUS: remove your foot from the
brake pedal.
X Briefly pull the cruise control lever
(Y page 175) towards you 0085.
or
X Accelerate briefly.
Your vehicle pulls away and adapts its
speed to that of the vehicle in front.
If no vehicle is detected in front, your vehi-
cle accelerates to the set speed.
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control.
If DISTRONIC PLUS detects that the vehicle in front has slowed down, it brakes your vehicle.
In this way, the distance you have selected is maintained. 176
Driving systemsDriving an
d parking