2020 MERCEDES-BENZ METRIS lock

is an increased danger of skidding and acci-
dents.
Only use the parking brake to brake the
vehicle 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. The brake lamps are not illuminated when you
brake the vehicle using the parking brake.
As a rule, you may only apply the parking
brake when the vehicle is stationary.
X To apply the parking brake: depress park-
ing brake pedal ; firmly.
The red F (only USA) or J (only Can-
ada) indicator lamp in the instrument cluster
lights up if the engine is running.
X To release the parking brake: depress the
brake pedal and keep it depressed.
X Pull release handle :.
The parking brake is released abruptly. The
red F (only USA) or J (only Canada)
indicator lamp in the instrument cluster
goes out.
Exceptionally, if the service brake fails, the
parking brake can be used to brake the vehicle
in an emergency.
X Emergency braking: pull release handle :
and gradually depress parking brake
pedal ;. Switching off the engine
Important safety notes G
WARNING
The automatic transmission switches to neu-
tral position N when you switch off the
engine. The vehicle may roll away. There is a
risk of an accident.
After switching off the engine, always switch
to parking position P. Prevent the parked
vehicle from rolling away by applying the
parking brake.
! If the coolant temperature is very high, e.g.
after driving on hilly roads, leave the engine
running at idle speed for about
two minutes
before turning it off.
This allows the coolant temperature to
return to normal.
Vehicles with automatic transmission X
Stop the vehicle.
X Shift the transmission to position j.
X Apply the parking brake.
X Turn the key to position u in the ignition
lock and remove it.
The immobilizer is activated.
If you switch the engine off with the trans-
mission in position k or h, the automatic
transmission shifts to i automatically.
If you then open one of the front doors or
remove the key, the automatic transmission
automatically shifts to j.
If you shift the automatic transmission to
i before switching off the engine, the
automatic transmission remains in i even
if a front door is opened.
X Secure the vehicle to prevent it from rolling
away

(Y page 138). Parking
139
Driving and parking Z

of the journey. Make sure that you do not
endanger 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 inspec-
tion 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 thick-
ness never falls below
0.12 in (3 mm). Have
the brake pads checked and replaced at a
qualified specialist workshop, if necessary.
Do not solely rely on the brake pad wear sen-
sor.
It is strongly recommended that you have the
brake pads checked at a qualified specialist
workshop at every service displayed in the
maintenance 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, compen-
sate 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:
R brake discs that have been approved by
Mercedes-Benz
R brake 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
workshop. When replacing the brake discs,
always have the brake pads/linings replaced
at the same time. Parking brake G
WARNING
If you must brake the vehicle with the park-
ing brake, the braking distance is considera-
bly longer and the wheels could lock. There
is an increased danger of skidding and acci-
dents.
Only use the parking brake to brake the
vehicle 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
110 yds (100 m) at a maximum speed of
12 mph (20 km/h

).
The brake lamps are not illuminated when you
brake the vehicle using the parking brake. Driving in wet conditions
Hydroplaning G
WARNING
There is a danger of hydroplaning occurring,
even if you are driving slowly and your tires
have sufficient tread depth, depending on
the depth of water on the road. There is a
risk of an accident.
For this reason, avoid tire ruts and brake
carefully.
Therefore, in heavy rain or other conditions in
which hydroplaning can occur, drive as fol-
lows:
R reduce your speed
R avoid tire ruts
R apply the brakes with care Driving tips
143
Driving and parking Z

Always pay careful attention to the traffic
situation and be ready to brake. G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist can:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake. Terminate
the intervention in a non-critical driving sit-
uation.
In particular, the detection of obstacles can be
impaired in the case of:
R dirt on the sensors or anything else covering
the sensors
R snow or heavy rain
R interference from other radar sources
R strong radar reflections, for example, in
parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a 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
accident 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 vehi-
cle, have the configuration and operation of
the radar sensor checked at a qualified spe-
cialist workshop. This also applies to collisions
at slow speeds where there is no visible dam-
age to the front of the vehicle.
If you change wheel size, make sure they cor-
respond to the correct wheel size category
(Y page
278). If the category is changed with- out 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,
Adaptive Brake Assist can detect obstacles
that have been in the path of your vehicle for
an extended period of time. Adaptive Brake
Assist does not react to stationary obstacles.
If Adaptive Brake Assist detects a risk of colli-
sion with a vehicle traveling in front or with a
stationary obstacle, the system calculates the
braking force necessary 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.
X Brake 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:
R you release the brake pedal
R there is no longer any danger of a collision
R no obstacle is detected in front of your vehi-
cle
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 sen-
sors in the bumper. It supports you from
speeds of approximately

20 mph (30 km/h). A
warning display in the exterior mirrors draws
your attention to vehicles detected in the
monitored area. If you then switch on the cor-
responding turn signal to change lane, you will
also receive an optical and audible collision
warning. Driving systems
151
Driving and parking Z

Warning display
Blind Spot Assist is not active at speeds below
approximately
20 mph (30 km/h). Vehicles in
the monitoring range are then not indicated.
If a vehicle is detected within the monitoring
range of Blind Spot Assist at speeds above
approximately 20 mph (30 km/h), warning
lamp : lights up red in the exterior mirror on
the corresponding side. Warning lamp :
always lights up when a vehicle enters the
blind spot monitoring range from behind or
from the side. When you overtake a vehicle,
the warning only occurs if the difference in
speed is less than 7 mph (11 km/h).
If you select reverse gear, Blind Spot Assist is
inactive.
The intensity of warning lamps : depends on
the brightness of the ambient light and is con-
trolled automatically.
Collision warning If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the cor-
responding turn signal, a double warning tone
sounds once. The warning lamp in the corre-
sponding exterior mirror flashes. If the turn
signal remains on, detected vehicles are indi-
cated by the flashing of the warning lamp in
the exterior mirror. There are no further warn-
ing tones.
Activating Blind Spot Assist X
Make sure that Blind Spot Assist is activa-
ted in the on-board computer (Y page

191).
X Turn the key to position 2 in the ignition
lock.
The warning lamps in the exterior mirrors
light up for approximately

1.5 seconds. Status indicators in the status overview submenu
If Blind Spot Assist is activated, the display
shows symbol : in the Status Overview
submenu of the on-board computer
(Y page

189). If you are driving faster than
20 mph (30 km/h), the symbol also shows
radar waves ; between the two vehicles.
Blind Spot Assist is then ready for use.
Towing a trailer If you attach a trailer, make sure that you have
correctly established the electrical connection.
This can be accomplished by checking the
trailer lighting. Blind Spot Assist is then deacti-
vated and the Blind Spot Assist Cur‐
rently Unavail. See Operator's Manual
message appears in the display. Lane Keeping Assist
General notes Lane Keeping Assist monitors the area in front
of your vehicle by means of camera : which
is mounted at the top of the windshield. Lane
Keeping Assist detects lane markings on the
road and can warn you before you leave your
lane unintentionally.
This function is available in the range between
40 mph (60 km/h

) and 125 mph (200 km/h).
A warning may be given if a front wheel
touches a lane marking. It will warn you by Driving systems
153
Driving and parking Z

For vehicles with steering wheel buttons you
can have the current ATTENTION ASSIST
(Attention Level) assessment displayed.
X Select Status Overview in the Assist.
menu and display the attention level
(Y page
189).
The following information is displayed: R the length of the journey since the last
break.
R the attention level determined by ATTEN-
TION ASSIST, displayed in a bar display in
five levels from low to high.
R if ATTENTION ASSIST is unable to calculate
the attention level and cannot output a
warning, the System Passive message
appears in the display. The bar display is
then dimmed. This is the case, for example,
if you are predominantly driving at a speed
below

40 mph (60 km/h) or above 125 mph
(200 km/h).
Activating ATTENTION ASSIST X
Activating ATTENTION ASSIST with the on-
board computer:
R on vehicles without steering wheel but-
tons

(Y page 180)
R on vehicles with steering wheel buttons
(Y page 190)
For vehicles with steering wheel buttons,
the system determines the attention level of
the driver depending on the setting selec-
ted:
Standard: the sensitivity with which the
system 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: R on vehicles without steering wheel buttons,
the À indicator lamp in the instrument
cluster lights up
R on vehicles with steering-wheel buttons, the
display shows the À symbol:
- in the status area
- in the Status Overview of the Assist.
menu (Y page

189)
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 corre-
sponds to the last selection activated – stand-
ard or sensitive.
If you switch off ATTENTION ASSIST in a vehi-
cle without steering wheel buttons, the system
remains switched off even after you start the
engine. The status of the system after switch-
ing 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! or Attent.
Asst: Take Break!is shown in the display.
An additional warning tone sounds.
X If necessary, take a break.
X Confirm 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 contin-
ues to detect increasing lapses in concentra-
tion, 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
visually and audibly the distance between your
vehicle and an object.
Your vehicle features two separate sound
emitters with different frequencies for the
warning tones. The warning ranges in front of
and behind the vehicle are indicated by differ-
ent warning tones.
PARKTRONIC is activated automatically when
you:
R turn the key to position 2 in the ignition lock
R release the parking brake and
R move the selector lever to position D, N or R156
Driving systems
Driving and parking

Towing a trailer
PARKTRONIC detects a coupled trailer if your
vehicle is equipped with the corresponding
electrical installations for trailer towing.
PARKTRONIC is deactivated for the rear area
when you establish an electrical connection
between your vehicle and a trailer. If you use
an adapter for the socket, remove it from the
socket after detaching the trailer. Otherwise,
PARKTRONIC remains deactivated for the rear
area.
Problems with PARKTRONIC Problem
Possible causes/consequences and
M SolutionsOnly the red segments
in the PARKTRONIC
warning displays are lit.
In addition, a warning
tone sounds for approx.
two seconds
PARKTRONIC is then
deactivated.
The indicator lamp of
the f button lights
up and the red seg-
ments in the
PARKTRONIC warning
display go out. PARKTRONIC has malfunctioned and has switched itself off.
X
If problems persist, have PARKTRONIC checked at a qualified
specialist workshop. The PARKTRONIC warn-
ing displays implausible
distances.
For example, all the
segments may be lit
even though there is no
obstacle present. The PARKTRONIC sensors are dirty or iced up.
X Clean the PARKTRONIC sensors ( Y page 267).
X Turn the key to position 2 in the ignition lock. The license plate or other parts attached near the sensors may not
be secured correctly.
X Check the license plate and attachment parts near the sensors
for correct seating. An external radio or ultrasonic source may be causing interference.
X Check PARKTRONIC functions in a different location. Active Parking Assist
General notes Active Parking Assist is an electronic parking
aid. The system uses ultrasound sensors to
measure the road on both sides of the vehicle
and indicates suitable parking spaces. It can
then actively steer and brake the vehicle to
help you to park and exit the parking space.
Active Parking Assist includes the
PARKTRONIC parking aid which indicates visu-
ally and audibly the distance between your vehicle and an obstruction. To do this,
PARKTRONIC uses the ultrasonic sensors of
the Active Parking Assist

(Y page 156).
Important safety notes Active Parking Assist is only an aid. It is not a
substitute for your attention to the immediate
surroundings. You are responsible for safe
maneuvering, parking and pulling away. Make
sure that no persons, animals or objects are in
the maneuvering range. Driving systems
159
Driving and parking Z

Active Parking Assist does not assist you park-
ing in spaces at right angles to the direction of
travel if:
R two parking spaces are located directly next
to one another
R the parking space is directly next to a low
obstacle such as a low curb
R you forward park
Active Parking Assist does not assist you park-
ing in spaces that are parallel or at right angles
to the direction of travel if:
R the parking space is on a curb
R the system reads the parking space as being
blocked, for example by foliage or grass
paving blocks
R the area is too small for the vehicle to
maneuver into
R the parking space is bordered by an obsta-
cle, e.g. a tree, a post or a trailer :
Detected parking space on the left
; Parking symbol
= Detected parking space on the right
If the driver's seat belt is fastened and all
doors are closed, Active Parking Assist is acti-
vated automatically when driving forwards.
The system is operational at speeds of up to
approximately
22 mph (35 km/h). While in
operation, the system independently locates
and measures parking spaces on both sides of
the vehicle.
Active Parking Assist will only detect parking
spaces:
R parallel or at right angles to the direction of
travel
R that are parallel to the direction of travel
and are at least 59 in (1.5 m) wide
R that are parallel to the direction of travel
and at least 40 in (1.0 m) longer than your
vehicle
R that are at right angles to the direction of
travel and at least 40 in (1.0 m) wider than
your vehicle i
Note that Active Parking Assist cannot
measure the length of a parking space if it is
at right angles to the direction of travel. You
will need to judge whether your vehicle will
fit in the parking space.
When the vehicle is driving at speeds of up to
approximately

20 mph (30 km/h), parking
symbol ; is shown as a status display in the
header.
The system detects and differentiates between
parking spaces which are parallel or at right
angles to the direction of travel. When a park-
ing space is detected, an arrow appears next
to parking symbol ; to indicate which side
the parking space is on. The parking space is
displayed while you are driving past it and until
you are approximately 50 ft (15 m) away from
it.
Active Parking Assist displays parking spaces
on the passenger side as standard. The park-
ing spaces on the driver's side are only dis-
played if you operate the turn signal on the
driver's side. When parking on the driver's
side, you must operate the turn signal until
you have started active parking assistance by
pressing the a button on the steering
wheel.
Parking G
WARNING
If you leave the driver's seat when the vehi-
cle is only being braked by Active Parking
Assist, the vehicle could roll away if:
R there is a malfunction in the system or in
the voltage supply.
R the electrical system in the engine com-
partment, the battery or the fuses are
tampered with.
R the battery is disconnected.
R the vehicle is accelerated, e.g. by a vehi-
cle occupant.
There is a risk of an accident.
Before leaving the driver's seat, always
secure the vehicle against rolling away.
If PARKTRONIC detects obstacles, Active Park-
ing Assist brakes automatically during the
parking process. You are responsible for brak-
ing in good time. Driving systems
161
Driving and parking Z

Switching the rear view camera on or
off
X
To activate: make sure that the key is in
position 2 in the ignition lock.
X Shift the transmission to position k.
On vehicles with a tailgate, the rear view
camera flap opens. The audio display shows
the area behind the vehicle. The rear area
shown is divided by guide lines.
In vehicles with a trailer coupling installed, the
function mode of the rear view camera can be
switched over when the trailer is reached. The
rear view camera then changes the viewing
angle and shows a locating aid for the ball cou-
pling of the trailer tow hitch to help reach the
drawbar.
X To switch function mode: select and con-
firm "Reverse parking" function : or "Cou-
pling up a trailer“ function ; using the
audio system control knob.
Information on the audio system control
knob can be found in the separate operating
instructions.
The symbol of the selected function is high-
lighted.
X To switch off: shift the transmission to
position i or h.
The dynamic guide lines are hidden and
after about 15 seconds the rear view cam-
era switches itself off.
or X Drive forwards more than about 30 ft
(10 m).
or X Drive forwards faster than 6 mph
(10 km/h
).
or X Shift the automatic transmission to position
j. In vehicles with Active Parking Assist, the rear
view camera remains switched on after the ini-
tial shift to reverse gear for the whole duration
of active parking assistance. You can find
information on active parking assistance under
"Active Parking Assist“

(Y page 159).
Messages in the multimedia system
display :
Yellow guide line at a distance of approx-
imately
13 ft (4.0 m) from the rear of the
vehicle
; White guide line without turning the steer-
ing wheel, vehicle width including the exte-
rior mirrors (static)
= Yellow guide line for the vehicle width
including the exterior mirrors, at the cur-
rent steering angle (dynamic)
? Yellow lane marking the course the tires
will take at the current steering angle
(dynamic) A
Yellow guide line at a distance of approx-
imately

3 ft (1.0 m) from the rear of the
vehicle
B Red guide line at a distance of approx-
imately

12 in (0.30 m) from the rear of the
vehicle
C Bumper
D Vehicle center axis (locating aid) Driving systems
165
Driving and parking Z