2018 MERCEDES-BENZ METRIS sensor

!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. The brakes are cooled down
more quickly in the airflow.
Wet road surfaces
If you have been driving for a long time in heavy
rain without braking, there may be a delayed
response when you first apply the brakes. This
may also occur after driving through a car wash
or deep water.
You must depress the brake pedal more firmly.
Maintain a longer distance to the vehicle in
front.
While paying attention to the traffic conditions,
you should brake the vehicle firmly after driving
on a wet road surface or through a car wash. This
heats the brake discs, so that they dry more
quickly, which protects them against corrosion.
Limited braking performance on salt-
treated roads
When driving on salted roads, salt may start to
build up on the brake disks and brake pads. This can increase braking distances considerably.
Maintain a greater distance to the vehicle in
front.
To remove any build-up of salt that may have
formed:
XApply the brakes at the start of the journey,
occasionally during journey and at the end of
the journey. Make sure that you do not endan-
ger other road users when doing so.
Checking the brake pad thickness
In addition to monitoring using the brake pad
wear sensor, regularly monitor and check all of
the brake pads by performing a visual inspection
to look for pad material wear.
If you are unable to check the brake wear on the
inside of the wheels, remove the wheels with the tools provided.
Make sure that the brake pad material thickness
never falls below 0.12 in (3 mm). Have the brake pads checked and replaced at a qualified spe-
cialist workshop, if necessary. Do not solely rely on the brake pad wear sensor.
It is strongly recommended that you have the
brake pads checked at a qualified specialist
workshop at every service displayed in the main-
tenance interval indicator, prior to long journeys
and whenever the wheels are removed.
New brake discs and brake pads/
linings
New brake pads and brake discs only reach their
optimal braking effect after about 60 miles
(100 kilometers). Until then, compensate for
this by applying greater force to the brake pedal.
For safety reasons, Mercedes-Benz recom-
mends only installing the following brake discs
and brake pads/linings:
Rbrake discs that have been approved by
Mercedes-Benz
Rbrake pads/linings that have been approved
by Mercedes-Benz or are of an equivalent
standard of quality
Other brake discs or brake pads/linings can
compromise the safety of your vehicle.
Always replace all brake discs or brake pads/
linings on an axle at the same time and only have
them replaced at a qualified specialist work-
shop. When replacing the brake discs, always
have the brake pads/linings replaced at the
same time.
Parking brake
GWARNING
If you must brake the vehicle with the parking brake, the braking distance is considerably
longer and the wheels could lock. There is an
increased danger of skidding and accidents.
Only use the parking brake to brake the vehi-
cle when the service brake is faulty. Do not
apply the parking brake too firmly. If the
wheels lock, release the parking brake until
the wheels begin turning again.
When driving on wet roads or dirt-covered sur-
faces, road salt and/or dirt may get into the
parking brake. This causes corrosion and a
reduction of braking force.
In order to prevent this, drive with the parking
brake lightly applied from time to time. When
doing so, drive for a distance of approximately
140Driving tips
Driving and parking

The last speed set remains stored. The last
speed stored is deleted when you switch off the
engine.
Cruise control is deactivated automatically
when:
Ryou apply the brakes
Ryou apply the parking brake and theF
(only USA) or J(only Canada) indicator
lamp in the instrument cluster lights up
Ryou are driving slower than 20 mph (30 km/h)
Ryou shift to neutral iwhile th evehicl eis in
motion
RES P®intervenes or you deactivat eES P®
Rthere is amalfunction in th eES P®or AB Ssys-
te m
If cruise control automatically deactivates, a
warnin gtone sounds and th eCruise
Contro lOffmessage appears briefl yin th edisplay.
The V symbol and th edisplay of th estore d
speed in th eheader or in th estatu sarea of th e
display are then no tshown.
Problems with cruise contro l
The speed cannotbe set when cruise control is
activated.
The display is showin g amessage of high priority
and canno ttherefor esho w a chang ein speed.
XProceed as instructe dby th emessage in th e
display.
COLLISION PREVENTION ASSIST
Gene ral notes
COLLISION PREVENTION ASSIST help syou:
Rto minimiz eth eris kof afront-en dcollision
wit h a detecte dobstacle in th epat hof your
vehicl e
Rto reduce th econsequence sof acollision
wit hth evehicl ein fron t
The system uses rada rsensor sto detec tvehi-
cle sin front.
COLLISION PREVENTION ASSIST consist sof th e
distanc ewarnin gfunction and Adaptive Brake
Assist.
If COLLISION PREVENTION ASSIST is malfunc -
tioning, th edisplay shows acorrespondin gmes -
sage (
Ypage 216).
Distance warning function
Important safety notes
GWARNIN G
The distanc ewarnin gfunction does no treact:
Rto people or animals
Rto oncomin gvehicles
Rto crossin gtraffic
Rwhen cornering
Thus ,th edistanc ewarnin gfunction canno t
provid e awarnin gin all critica lsituations.
There is aris kof an accident.
Always pay careful attention to th etraffic sit -
uation and be read yto brake.
GWARNIN G
The distanc ewarnin gfunction canno talways
clearly identify objects and complex traffic
situations.
In suc hcases, th edistanc ewarnin gfunction
may:
Rgiv ean unnecessary warnin g
Rnotgiv e a warnin g
There is aris kof an accident.
Always pay careful attention to th etraffic sit -
uation and do no trel ysolely on th edistanc e
warnin gfunction .
In particular, th edetection of obstacles can be
impaire din th ecas eof:
Rdir ton th esensor sor anythin gelse coverin g
th esensor s
Rsnow or heav yrain
Rinterferenc efrom other rada rsource s
Rstrongrada rreflections, for example, in park -
in g garages
Ranarrow vehicl etravelin gin front, e.g. a
motorbik e
Ravehicl etravelin gin fron ton adifferen tlin e
Due to th enature of th esystem, particularly
complicate dbut non-critica ldrivin gcondition s
may also caus eth esystem to display awarning.
If you fail to adapt your drivin gstyle, th edis-
tance warnin gfunction can neither reduce th e
ris kof an acciden tno roverride th elaws of phys -
ics .The distanc ewarnin gfunction canno ttak e
146Driving systems
Driving and parking

into account road, weather or traffic conditions.
The distance warning function is only an aid. You
are responsible for the distance to the vehicle in
front, for vehicle speed, braking in good time
and for staying in your lane.
Following damage to the front end of the vehicle,
have the configuration and operation of the
radar sensor checked at a qualified specialist
workshop. This also applies to collisions at slow
speeds where there is no visible damage to the
front of the vehicle.
If you change wheel size, make sure they corre- spond to the correct wheel size category
(
Ypage 279). If the category is changed without
recoding the control units in the vehicle, the
functioning of the distance warning feature may
be impaired. COLLISION PREVENTION ASSIST
may then detect a malfunction and switch itself
off.
Operation
XTo activate/deactivate: activate or deacti-
vate the distance warning function in the on-
board computer (
Ypage 187).
If the distance warning function of COLLISION
PREVENTION ASSIST is activated, the display
shows the Äsymbol:
Rin the header
Rin the Status Overviewof the Assist.menu (Ypage 186)
At speeds up to approx 20 mph (30 km/h) the
display in vehicles with Active Parking Assist
first shows the ístatus indicator. Only up to
a speed of about 20 mph (30 km/h) does the display show the Äsymbol instead of the
í status indicator.
The distance warning function can help you to
minimize the risk of a front-end collision with a
vehicle ahead or reduce the effects of such a
collision. With the help of the radar sensor sys-
tem, the distance warning function can detect
obstacles that are in the path of your vehicle for
an extended period of time. If the distance warn-
ing function detects that there is a risk of a col-
lision, you will be warned visually and, where
necessary, acoustically. Without your interven-
tion, the distance warning function cannot pre-
vent a collision.
The distance warning function issues a warning
at speeds:
Rfrom about 4 mph (7 km/h) if you approach a
vehicle traveling in front or a stationary vehi-
cle too quickly. The ·warning lamp in the instrument cluster then lights up and an inter-
mittent warning tone also sounds.
At speeds up to about 45 mph (70 km/h), the
system also detects stationary obstacles, for
example stopped or parked vehicles.
XBrake immediately until the distance from the
obstacle increases and the risk of a front-end
collision passes.
or
XTake evasive action, provided it is safe to do
so.
Adaptive Brake Assist
General notes
Adaptive Brake Assist evaluates the traffic sit-
uation with the help of the radar sensor system and can detect obstacles which have been in
your vehicle's path for an extended period of
time. From speeds above 4 mph (7 km/h), Adap-
tive Brake Assist aids you in braking during haz-
ardous situations.
Up to a speed of approximately 125 mph
(200 km/h), Adaptive Brake Assist is capable of
reacting to moving obstacles that have already
been detected as such at least once over the
period of observation.
Important safety notes
GWARNING
Adaptive Brake Assist does not react:
Rto people or animals
Rto oncoming vehicles
Rto crossing traffic
Rto stationary obstacles
Rwhen 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.
GWARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
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In such cases, Adaptive Brake Assist can:
Rintervene unnecessarily
Rnot 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.
In particular, the detection of obstacles can be
impaired in the case of:
Rdirt on the sensors or anything else covering
the sensors
Rsnow or heavy rain
Rinterference from other radar sources
Rstrong radar reflections, for example, in park-
ing garages
Ra narrow vehicle traveling in front, e.g. a
motorbike
Ra vehicle traveling in front on a different line
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause Adaptive Brake Assist to inter-
vene.
If you fail to adapt your driving style, Adaptive
Brake Assist can neither reduce the risk of acci-
dent nor override the laws of physics. Adaptive
Brake Assist cannot take into account road,
weather or traffic conditions. Adaptive Brake
Assist is only an aid. You are responsible for the
distance to the vehicle in front, for vehicle
speed, braking in good time and for staying in
your lane.
Following damage to the front end of the vehicle,
have the configuration and operation of the
radar sensor checked at a qualified specialist
workshop. This also applies to collisions at slow
speeds where there is no visible damage to the
front of the vehicle.
If you change wheel size, make sure they corre- spond to the correct wheel size category
(
Ypage 279). If the category is changed without
recoding the control units in the vehicle, the
functioning of Adaptive Brake Assist may be
impaired. COLLISION PREVENTION ASSIST may
then detect a malfunction and switch itself off.
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.
Operation
With the help of the radar sensor system, Adap-
tive Brake Assist can detect obstacles that have been in the path of your vehicle for an extended
period of time. Ada

ptive Brake Assist does not
react to stationary obstacles. If Adaptive Brake
Assist detects a risk of collision with a vehicle
traveling in front or with a stationary obstacle,
the system calculates the braking force neces-
sary to avoid this collision. If you apply the
brakes forcefully, Adaptive Brake Assist will
automatically increase the braking force to a
level suitable for the traffic conditions.
XBrake until the distance to the obstacle
increases and the risk of a collision passes.
ABS prevents the wheels from locking.
The brakes function as usual again if:
Ryou release the brake pedal
Rthere is no longer any danger of a collision
Rno obstacle is detected in front of your vehicle
Braking assistance is then ended.
Blind Spot Assist
General notes
Blind Spot Assist monitors the areas on either
side of the vehicle that are not visible to the
driver with two lateral, rear-facing radar sensors
in the bumper. It supports you from speeds of
approximately 20 mph (30 km/h). A warning
display in the exterior mirrors draws your atten-
tion to vehicles detected in the monitored area.
If you then switch on the corresponding turn
signal to change lane, you will also receive an
optical and audible collision warning.
Important safety notes
GWARNING
Blind Spot Assist does not react to:
Rvehicles overtaken too closely on the side,
placing them in the blind spot area
Rvehicles which approach with a large speed
differential and overtake your vehicle
As a result, Blind Spot Assist may not give
warnings in such situations. There is a risk of
an accident.
148Driving systems
Driving and parking

Always observe the traffic conditions care-
fully, and maintain a safe lateral distance.
Blind Spot Assist is only an aid. It may fail to
detect some vehicles and is no substitute for
attentive driving. Always ensure that there is
sufficient distance to the side for other road
users and obstacles.
In particular, the detection of obstacles can be
impaired in the case of:
Rdirt on the sensors or anything else covering
the sensors
Rfog, heavy rain or snow
Rnarrow vehicles, e.g. motorcycles or bicycles
Rvery wide lanes
Rnarrow lanes
Rvehicles not driving in the middle of their lane
Rbarriers or other road boundaries
Vehicles in the monitoring range are then not
indicated.
iUSA only:
This device has been approved by the FCC as
a "Vehicular Radar System". The radar sensor
is intended for use in an automotive radar
system only. Removal, tampering, or altering
of the device will void any warranties, and is
not permitted by the 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.
Monitoring range of the sensors
Blind Spot Assist monitors the area shown in the
diagram up to 118 in (3 m) behind and directly
next to your vehicle.
If the lanes are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may be
indicated, especially if the vehicles are not driv-
ing in the middle of their lane. This may be the
case if the vehicles are driving on the inner side
of their lane.
Due to the nature of the system:
Rwarnings may be issued in error when driving
close to crash barriers or similar solid lane
borders.
Rwarnings may be interrupted when driving
alongside long vehicles, e.g. trucks, for a pro-
longed time.
The two sensors for Blind Spot Assist are inte-
grated into the sides of the rear bumper. Make
sure that the bumper is free of dirt, ice or slush
in the vicinity of the sensors. The radar sensors
must not be covered, for example by rear-moun- ted cycle racks or overhanging loads. Following
a severe impact or in the event of damage to the
bumper, have the function of the radar sensors
checked at a qualified specialist workshop.
Blind Spot Assist may otherwise not work prop-
erly.
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XSelectStatus Overviewin theAssist.menu and display the attention level
(Ypage 186).
The following information is displayed:
Rthe length of the journey since the last break.
Rthe attention level determined by ATTENTION
ASSIST, displayed in a bar display in five levels
from low to high.
Rif ATTENTION ASSIST is unable to calculate
the attention level and cannot output a warn-
ing, the System
Passivemessage appears in
the display. The bar display is then dimmed.
This is the case, for example, if you are pre-
dominantly driving at a speed below 40 mph
(60 km/h) or above 125 mph (200 km/h).
Activating ATTENTION ASSIST
XActivating ATTENTION ASSIST with the on-
board computer:
Ron vehicles without steering wheel buttons
(Ypage 177)
Ron vehicles with steering wheel buttons
(Ypage 187)
For vehicles with steering wheel buttons, the
system determines the attention level of the
driver depending on the setting selected:
Standard: the sensitivity with which the sys-
tem determines the attention level is set to
normal.
Sensitive: the sensitivity is set higher. The
driver is warned earlier.
When ATTENTION ASSIST is switched on and
the vehicle engine is running:
Ron vehicles without steering wheel buttons,
the À indicator lamp in the instrument
cluster lights up
Ron vehicles with steering-wheel buttons, the
display shows the Àsymbol:
-in the status area
-in the Status Overviewof the Assist.menu (Ypage 186)
For vehicles with steering wheel buttons, if you
deactivate ATTENTION ASSIST, the system is
automatically re-activated when you start the
engine. The system sensitivity then corresponds
to the last selection activated – standard or sen-
sitive.
If you switch off ATTENTION ASSIST in a vehicle without steering wheel buttons, the system
remains switched off even after you start the engine. The status of the system after switching
on the engine always corresponds to the status
last selected.
Warning in the display
If the system detects tiredness or increasing
lapses in concentration, the warning
Atten‐
tion Assist: Take a Break!orAttent.Asst: Take Break!is shown in the display.
An additional warning tone sounds.
XIf necessary, take a break.
XConfirm the message by pressing the a
button on the steering wheel.
On long journeys, take regular breaks in good
time to allow yourself to rest. If you do not take
a break and ATTENTION ASSIST continues to
detect increasing lapses in concentration, you
will be warned again after 15 minutes at the
earliest. This will only happen if ATTEN-
TION ASSIST still detects typical indicators of
fatigue or increasing lapses in concentration.
PARKTRONIC
General notes
PARKTRONIC is an electronic parking aid. The
system is equipped with ultrasonic sensors in
the front and rear bumpers to monitor the area
around your vehicle. PARKTRONIC indicates vis-
ually and audibly the distance between your
vehicle and an object.
Your vehicle features two separate sound emit- ters with different frequencies for the warning
tones. The warning ranges in front of and behind
the vehicle are indicated by different warning
tones.
PARKTRONIC is activated automatically when
you:
Rturn the key to position 2in the ignition lock
Rrelease the parking brake and
Rmove the selector lever to position D,N or R
PARKTRONIC is deactivated at speeds above
11 mph (18 km/h). PARKTRONIC is reactivated
at speeds below 10 mph (16 km/h).
Important safety notes
PARKTRONIC is only an aid. It cannot replace
your own awareness of the immediate surround-
ings. You are responsible for safe maneuvering,
Driving systems153
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parking and pulling away. Make sure that there
are no persons, animals or objects in the maneu-
vering area while maneuvering and parking in/
leaving parking spaces.
!Pay particular attention to obstacles above
or below the sensors when parking, such as
flower pots or trailer towbars. PARKTRONIC
does not recognize such objects when they
are in the immediate vicinity of the vehicle.
You could damage the vehicle or objects.
PARKTRONIC can suffer interference from:
Rultrasonic sources such as a truck's
compressed-air brakes, an automatic car
wash or a pneumatic drill
Rattachments to the vehicle, e.g. rear moun-
ted racks
Rnumber plates (vehicle license plates) that
are not affixed flat against the bumper
Rdirty or icy sensors
Remove a detachable trailer coupling if it is no
longer required. PARKTRONIC measures the
minimum detection range to an obstacle from
the bumper, not the ball coupling.
Range of the sensors
PARKTRONIC does not account for obstacles
that are:
Rbeneath its detection range, e.g. persons, ani-
mals or objects
Rabove its detection range, e.g. overhanging
loads, overhangs or truck loading ramps
The sensors must be free of dirt, ice or slush.
Otherwise, they cannot function correctly.
Clean the sensors regularly, taking care not to
scratch or damage them (
Ypage 268).
Front sensors
CenterApprox. 39 in
(100 cm)
CornersApprox. 24 in (60 cm)
Rear sensors
CenterApprox. 47 in
(120 cm)
CornersApprox. 31 in (80 cm)
Minimum distance
CenterApprox. 8 in (20 cm)
CornersApprox. 8 in (20 cm)
If an obstacle is within this range, the corre-
sponding segments of the warning displays light
up and you hear a warning tone. If the distance
falls below the minimum, the distance from an
obstacle may no longer be shown.
154Driving systems
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Warning displays
Front area warning display in center of dashboard.
Rear area warning display on the dashboard
Rear area warning display in center of headliner in
rear compartment.
:
Warning segments for the left side of the
vehicle
;Warning segments for the right side of the
vehicle
=Segments showing operational readiness
The warning displays show the distance
between the sensor and the obstacle.
The warning display is divided into five yellow
and two red segments for each side of the vehi- cle. PARKTRONIC is operational if operational
readiness indicator
=lights up.
There is a malfunction if only the red segments
of the warning display light up (
Ypage 156).
The selected transmission position determines
whether the front and/or rear area is monitored.
Selector lever posi-
tionMonitoring
hFront area
k oriFront and rear area
jNo areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the vehi-
cle's distance from the obstacle. In addition,
warning tones are emitted.
When the distance to the obstacle is sufficient,
you will hear an intermittent warning tone. When
the distance to the obstacle is sufficient, you will
hear an intermittent warning tone. When the
minimum distance is reached, you hear a con-
tinuous warning tone.
Roll-back warning
Regardless of transmission position,
PARKTRONIC automatically monitors the area
behind the vehicle if the vehicle begins to roll
backwards, e.g. after stopping on an uphill gra-
dient.
Activating/deactivating PARKTRONIC
XPress the fbutton.
If PARKTRONIC is deactivated, the indicator
lamp in the switch lights up.
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