2020 MERCEDES-BENZ METRIS check engine light

Problem
Possible causes/consequences and
M SolutionsIt is no longer possible
to lock or unlock the
vehicle using the Smart-
Key. The SmartKey battery is weak or discharged.
X Point the tip of the SmartKey at the driver's door handle from
very close range and press the % or & button.
If this does not work:
X Replace the SmartKey battery ( Y page 73).
or
X Lock or unlock the vehicle using the mechanical key ( Y page
73).The SmartKey is faulty.
X Lock the vehicle with the mechanical key (Y page
73).
X Have the SmartKey checked at a qualified specialist workshop. The engine cannot be
started using the Smart-
Key. The on-board voltage is too low.
X Switch off all non-essential consumers, such as interior lighting,
and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page

262).
or
X Jump-start the vehicle ( Y page
272).
or
X Consult a qualified specialist workshop. You have lost a Smart-
Key. X
Have the SmartKey deactivated at a qualified specialist work-
shop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the mechanical locks replaced. You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the mechanical locks replaced. Central locking
Important safety notes
G
WARNING
If children are left unsupervised in the vehi-
cle, they could, in particular:
R open doors, thereby endangering other
persons or road users.
R get out and be struck by oncoming traffic.
R operate vehicle equipment and become
trapped, for example. In addition, children could set the vehicle in
motion, for example, if they:
R release the parking brake.
R change the transmission position.
R start the vehicle.
There is a risk of accident and injury.
Never leave children unsupervised in the
vehicle.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle.
Keep the SmartKey out of the reach of chil-
dren. Central locking
75
Opening and closing Z

Key positions
g
To insert/remove the key, to lock the
steering wheel
1 To unlock the steering wheel, power sup-
ply for some consumers (e.g. the radio)
2 To switch on the ignition, power supply for
all consumers, preglow and drive position
3 To start the engine
i If the key does not belong to the vehicle, it
can still be turned in the ignition lock. How-
ever, the ignition will not be switched on.
The engine cannot be started. Preparing for a journey
Visual check of the vehicle exterior X
In particular, check the following compo-
nents on the vehicle, and on the trailer as
necessary:
R
license plates, vehicle lighting, turn sig-
nals, brake lamps and wiper blades for
dirt and damage
R tires and wheels for firm seating, correct
tire pressure and general condition
R trailer tow hitch for play and security
The trailer coupling is one of the most
important vehicle parts with regard to
road safety. Observe the notes on opera-
tion, care and maintenance of the trailer
tow hitch (see the manufacturer's operat-
ing instructions).
X Rectify any noticeable defects before com-
mencing the journey. Checks in the vehicle Emergency equipment/first-aid kit
X Check the equipment to make sure that it is
accessible, complete and ready for use.
The first aid and breakdown assistance equip-
ment is located:
R in the front door stowage compartments
R in the seat base of the left front seat
R in the rear stowage compartment on the
right-hand side of the vehicle
(Y page 270)
Vehicle lighting
X Turn the key to position 2 in the ignition
lock.
X Check the lighting system with the aid of a
second person.
X Replace defective bulbs (Y page
105). Before driving off
G
WARNING
Objects in the driver's footwell may restrict
the clearance around the pedals or block a
depressed pedal. This jeopardizes the oper-
ating and road safety of the vehicle. There is
a risk of an accident.
Stow all objects securely in the vehicle so
that they do not get into the driver's foot-
well. When using floormats or carpets, make
sure that they are properly secured so that
they do not slip or obstruct the pedals. Do
not place several floormats or carpets on
top of one another. G
WARNING
Unsuitable footwear can hinder correct
usage of the pedals, e.g.:
R shoes with thick soles
R shoes with high heels
R slippers
There is a risk of an accident.
Wear suitable footwear to ensure correct
usage of the pedals. Driving
127
Driving and parking Z

Problems with the engine
Problem
Possible causes/consequences and
M SolutionsThe engine does not
start.
The starter motor can
be heard. There is a malfunction in the fuel supply.
X
Turn the key back to position g in the ignition lock before
attempting to start the engine again.
X Start the engine again.
Please bear in mind that lengthy and frequent starting attempts
will drain the battery.
If the engine does not start after several attempts: X Consult a qualified specialist workshop. The engine does not
start.
The starter motor can
be heard. The reserve
fuel warning lamp is lit
and the fuel gauge is at
0. The fuel tank has been run dry.
X Refuel the vehicle. The engine does not
start.
The starter motor can-
not be heard. The on-board voltage is too low. The battery is too weak or dis-
charged.
X Jump-start the vehicle ( Y page 272).
If the engine cannot be jump-started, the starter motor is faulty.
X Consult a qualified specialist workshop. The engine does not
start.
The starter motor can-
not be heard. The battery is discharged or faulty.
X
Check the battery for damage.
X Charge the battery (Y page
262).The engine is not run-
ning smoothly and is
misfiring. There is a malfunction in the engine electronics or a mechanical
component of the engine management system.
X Only depress the accelerator pedal slightly.
Unburnt fuel may otherwise get into the catalytic converter and
damage it.
X Have the cause rectified immediately at a qualified specialist
workshop. Automatic transmission
Important safety notes
G
WARNING
The vehicle can suddenly accelerate if the
engine speed is above the engine idling
speed and you then select transmission position h or k. There is a risk of an acci-
dent.
When engaging transmission position
h or
k at a standstill, always keep the brake
pedal depressed firmly and do not depress
the accelerator pedal at the same time. 130
Automatic transmission
Driving and parking

The rear view camera is a visual parking aid. It
shows you the area behind the vehicle in the
audio display.
The area behind the vehicle is displayed in a
mirrored fashion, as in the rear-view mirror or
the exterior mirrors. The guide lines displayed
assist you in backing up.
The message displays depend on the language
setting of the audio system. The following rear
view camera displays are examples.
Important safety notes !
Objects that are not at ground level appear
further away than they actually are, for
example:
R the bumper of the vehicle parked behind
R the drawbar of a trailer
R the ball coupling of a trailer tow hitch
R the tail-end of a truck
R slanted posts
Only use the camera guide lines for orienta-
tion. Do not get any closer to objects than
the lowest horizontal guide line. You may
otherwise damage your vehicle and/or the
object.
The rear view camera is only an aid. It cannot
replace your own awareness of the immediate
surroundings. You are responsible for safe
maneuvering and parking. Make sure that
there are no persons, animals or objects in the
maneuvering area while maneuvering and
parking in parking spaces.
The rear view camera may show obstacles in
perspectival distortion, incorrectly or not at all.
The rear view camera cannot display all
objects located very near and/or under the
rear bumper. It does not warn you of a colli-
sion, persons or objects.
Under the following circumstances, the rear
view camera will not function, or will function
in a limited manner:
R if the tailgate or rear-end door is open.
R if it is raining very heavily or snowing, or it is
foggy.
R at night or in very dark places.
R if the camera is exposed to very bright light.
White lines may appear in the camera image
R if the area is lit by fluorescent light, e.g.
from fluorescent lamps or LED lighting.
The camera image may flicker. R
if the camera lens fogs up, e.g. when driving
into a heated garage in winter, causing a
rapid change in temperature.
R the camera lens is dirty or obstructed.
Observe the notes on cleaning.
(Y page
267)
R if the rear of the vehicle is damaged.
In this case, have the camera position and
setting checked at a qualified specialist
workshop.
R the display has pixel errors.
Have the display repaired or replaced if usa-
bility is significantly reduced due to pixel
errors.
Do not use the rear view camera in these sit-
uations. You could otherwise injure others or
damage objects and the vehicle while parking
and maneuvering.
The field of vision and other functions of the
rear view camera may be restricted due to
additional accessories on the rear of the vehi-
cle (e.g. license plate holder, rear-mounted
bicycle rack).
Guide lines are always shown at road level. In
trailer mode, the guide lines are shown at the
level of the trailer coupling.
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 rear view camera cannot be precisely cali-
brated. The guide lines at road level or at the
level of the trailer tow hitch will not be dis-
played correctly.
In vehicles with a tailgate, the rear view cam-
era is protected from raindrops and dust by
means of a flap. When the rear view camera is
activated, this flap opens.
The flap closes again when:
R you have finished the maneuvering process
R you switch off the engine
For technical reasons, the flap may remain
open briefly after the rear view camera has
been deactivated. 164
Driving systems
Driving and parking

Observe the following when towing a trailer:
R Practice driving around bends, stopping and
backing up at a place where there is no traf-
fic. This enables you to gain experience and
get used to the new handling characteris-
tics.
R Before driving, check:
- that the trailer tow hitch and ball coupling
are secure
- that the safety switch for a braked trailer
is functioning properly
- that the safety chains are secure and not
damaged
- that the electrical connections are secure
- that the lights are working
- that the wheels are in good order and the
tire pressure is correct
R Adjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
R If the trailer is equipped with a separate
functional braking system, check before
each journey whether the brakes are func-
tioning correctly.
R Secure the load on the trailer according to
the applicable specifications and current
standards on securing loads
(Y page 244).
R When driving with a trailer, check at regular
intervals that the load is secured and that
the brakes and lights are working.
R Bear in mind that the handling will be less
stable when towing a trailer than when driv-
ing without one. Avoid sudden steering
movements.
R The vehicle/trailer combination is heavier,
accelerates more slowly and has a
decreased gradient climbing capability and a
longer braking distance.
It is more susceptible to crosswinds and
requires cautious steering.
R If possible, do not brake suddenly, but
rather moderately at first so that the trailer
can activate its brakes. Then increase the
force on the brake pedal.
R If the automatic transmission repeatedly
shifts between gears when driving on
inclines, restrict the shift range. Select shift
range 4, 3, 2 or 1.
Driving in a low gear and at a low speed
reduces the risk of damaging the engine. R
When driving on a downhill gradient, shift to
a low gear and take advantage of the
engine's braking effect.
Avoid continuous brake application as this
may overheat the vehicle brakes and, if
installed, the trailer brakes.
R If the coolant temperature increases dra-
matically while the air-conditioning system
is switched on, switch off the air-condition-
ing system.
Coolant heat can also be dissipated by
switching the airflow and the temperature of
the air conditioning to the maximum level.
Open the windows if necessary.
R When overtaking, pay particular attention to
the extended length of your vehicle/trailer
combination.
Due to the length of your vehicle/trailer
combination you need an additional dis-
tance before you can return to your original
lane. Uncoupling a trailer
G
WARNING
If you uncouple a trailer with the overrun
brake engaged, you could trap your hand
between the vehicle and the trailer drawbar.
There is a risk of injury.
Do not uncouple a trailer if the overrun
brake is engaged.
! Do not disconnect a trailer with an
engaged overrun brake. Otherwise, your
vehicle could be damaged by the rebound-
ing of the overrun brake.
X Make sure that the selector lever of the
automatic transmission is in position P.
X Engage the vehicle's parking brake.
X Close all doors.
X Apply the parking brake of the trailer.
X In addition, secure the trailer against rolling
away with a wheel chock or similar object.
X Remove the trailer cable and safety chains
and decouple the trailer. Towing a trailer
171
Driving and parking Z

Safety systems
Display messages
Possible causes/consequences and
M SolutionsABS, ESP Inopera‐
tive
+
ABS, BAS, hill start assist, and ESP
®
as well as its driving safety sys-
tems are unavailable due to a malfunction.
ATTENTION ASSIST is deactivated and other driving systems could
be automatically deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you brake
hard, for example.
This causes steerability and braking to be greatly impaired. The
braking distance can increase in emergency braking situations.
If ESP ®
is not operational, ESP ®
will not stabilize the vehicle.
There is an increased risk of skidding and accidents.
X Switch the engine off, wait briefly and start the engine again.
X Check if the display message has disappeared and ESP ®
is opera-
tional.
X If the display message continues to be displayed:
R Drive on with care.
R Visit a qualified specialist workshop immediately. ABS, ESP Curr.
Unavail.
+
ABS, BAS, hill start assist, and ESP
®
as well as its driving safety sys-
tems are temporarily unavailable.
ATTENTION ASSIST is deactivated and other driving systems could
be automatically deactivated.
For example, the on-board voltage may be insufficient.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you brake
hard, for example.
This causes steerability and braking to be greatly impaired. The
braking distance can increase in emergency braking situations.
If ESP ®
is not operational, ESP ®
will not stabilize the vehicle.
There is an increased risk of skidding and accidents.
X Drive on with care and on a suitable stretch of road make slight
steering movements at a speed above 12 mph (20 km/h ).
X Switch the engine off, wait briefly and start the engine again.
X Check if the display message has disappeared and ESP ®
is opera-
tional.
X If the display message continues to be displayed:
R Drive on with care.
R Visit a qualified specialist workshop immediately.196
Display messages (vehicles without steering wheel buttons)
On-board computer and displays

Display messages
Possible causes/consequences and
M Solutions÷
Inoperative
+ ESP
®
, BAS and hill start assist are unavailable due to a malfunction.
ATTENTION ASSIST is deactivated and other driving systems could
be automatically deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance in an emergency braking situation can thus
increase.
If ESP ®
is not operational, ESP ®
will not stabilize the vehicle.
There is an increased risk of skidding and accidents.
X Switch the engine off, wait briefly and start the engine again.
X Check if the display message has disappeared and ESP ®
is opera-
tional.
X If the display message continues to be displayed:
R Drive on with care.
R Visit a qualified specialist workshop immediately. ÷
Currently Unavail.
+ ESP
®
, BAS and hill start assist are unavailable due to a malfunction.
The self-diagnosis function, for example, may not be complete.
ATTENTION ASSIST is deactivated and other driving systems could
be automatically deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you brake
hard, for example.
The braking distance in an emergency braking situation can thus
increase.
If ESP ®
is not operational, ESP ®
will not stabilize the vehicle.
There is an increased risk of skidding and accidents.
X Drive on with care on a suitable stretch of road, making make
slight steering movements at a speed above
12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
X Switch the engine off, wait briefly and start the engine again.
X Check if the display message has disappeared and ESP ®
is opera-
tional.
X If the display message continues to be displayed:
R Drive on with care.
R Visit a qualified specialist workshop immediately.200
Display messages (vehicles without steering wheel buttons)
On-board computer and displays

Display messages
Possible causes/consequences and
M SolutionsÐ
Power Steering Mal‐
function See Oper.
Manual An additional warning tone sounds. The steering power assistance
could be malfunctioning. You may need to steer more forcefully.
X Carefully continue to a qualified specialist workshop and have the
steering checked immediately. Â
Obtain a New Key The key needs to be replaced.
X Visit a qualified specialist workshop. Phone No Service Your vehicle is outside the network provider's transmitter/receiver
range. ¥
Check Washer Fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
X Add washer fluid (Y page 256).Indicator and warning lamps in the instrument cluster
General notes
When switching on the ignition, some systems carry out a self-test. Some indicator and warning
lamps may temporarily turn on or start to flash. This is not an indication of any problem. Only
when these indicator and warning lights turn on or start flashing after the engine has started or
during the journey has a malfunction occurred. Indicator and warning lamps in the instrument cluster
227
On-board computer and displays Z