2018 MERCEDES-BENZ METRIS check engine light

ProblemPossible causes/consequences andMSolutions
The SmartKey is faulty.
XLock the vehicle with the mechanical key (Ypage 71).
XHave the SmartKey checked at a qualified specialist workshop.
The engine cannot be
started using the Smart-
Key.The on-board voltage is too low.
XSwitch off all non-essential consumers, such as interior lighting, and
try to start the engine again.
If this does not work:
XCheck the starter battery and charge it if necessary (Ypage 264).
or
XJump-start the vehicle (Ypage 274).
or
XConsult a qualified specialist workshop.
You have lost a Smart-
Key.XHave the SmartKey deactivated at a qualified specialist workshop.
XReport the loss immediately to the vehicle insurers.
XIf necessary, have the mechanical locks replaced.
You have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.
XIf necessary, have the mechanical locks replaced.
Central locking
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
GWARNING
If persons, particularly children are subjected to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
You can open a locked door from the inside at
any time. For the sliding doors, the child-proof
locks must be deactivated.
Centrally locking and unlocking the
vehicle from the inside
You can centrally lock and unlock the whole
vehicle from the inside using the central locking
buttons on the driver's door.
Central locking73
Opening and closing
Z

ProblemPossible causes/consequences andMSolutions
The engine does not
start.
The starter motor cannot
be heard.The battery is discharged or faulty.
XCheck the battery for damage.
XCharge the battery (Ypage 264).
The engine is not running
smoothly and is misfir-
ing.There is a malfunction in the engine electronics or a mechanical com-
ponent of the engine management system.
XOnly depress the accelerator pedal slightly.
Unburnt fuel may otherwise get into the catalytic converter and
damage it.
XHave the cause rectified immediately at a qualified specialist work-
shop.
Automatic transmission
Important safety notes
GWARNING
If the engine speed is above the idling speed
and you engage transmission position Dor R,
the vehicle could pull away suddenly. There is
a risk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do not simultaneously accelerate.
GWARNING
The automatic transmission switches to neu-
tral position Nwhen you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
Before switching off the engine, always switch
to parking position P. Prevent the parked vehi-
cle from rolling away by applying the parking
brake.
!If the engine is switched off, rolling in neutral
N can damage the power transmission and
result in transmission damage.
Always observe the instructions and safety
notes under "Tow starting and towing away"
(
Ypage 276).
Bear in mind that power transmission between
the engine and the transmission is interrupted
when the engine is switched off. For this reason,
shift the automatic transmission to Pbefore the engine is switched off and with the vehicle is
stationary. Apply the parking brake to prevent
the vehicle from rolling away.
DIRECT SELECT lever
Overview of the transmission shift sys-
tem
jPark position with parking lock
kReverse gear
iNeutral
hDrive
The DIRECT SELECT lever is on the right of the
steering column.
The DIRECT SELECT lever always returns to its
original position. The display in the instrument
cluster shows the current transmission position,
namely P,R, Nor D(
Ypage 130).
128Automatic transmission
Driving and parking

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 exam-
ple:
Rthe bumper of the vehicle parked behind
Rthe drawbar of a trailer
Rthe ball coupling of a trailer tow hitch
Rthe tail-end of a truck
Rslanted 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 other-
wise 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 maneu- vering 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 collision, per-
sons or objects.
Under the following circumstances, the rear
view camera will not function, or will function in
a limited manner:
Rif the tailgate or rear door is open.
Rif it is raining very heavily or snowing, or it is
foggy.
Rat night or in very dark places.
Rif the camera is exposed to very bright light.
White lines may appear in the camera image
Rif the area is lit by fluorescent light, e.g. from fluorescent lamps or LED lighting.
The camera image may flicker.
Rif the camera lens fogs up, e.g. when driving
into a heated garage in winter, causing a rapid
change in temperature.
Rthe camera lens is dirty or obstructed.
Observe the notes on cleaning.
(
Ypage 269)
Rif the rear of the vehicle is damaged. In this case, have the camera position and
setting checked at a qualified specialist work-
shop.
Rthe 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 situa-
tions. You could otherwise injure others or dam-
age objects and the vehicle while parking and
maneuvering.
The field of vision and ot

her functions of the rear
view camera may be restricted due to additional accessories on the rear of the vehicle (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 corre-
spond to the correct wheel size category
(
Ypage 279). If the category is changed without
recoding the control units in the vehicle, the rear
view camera cannot be precisely calibrated. The
guide lines at road level or at the level of the
trailer tow hitch will not be displayed correctly.
In vehicles with a tailgate, the rear view camera
is protected from raindrops and dust by means
of a flap. When the rear view camera is activa-
ted, this flap opens.
The flap closes again when:
Ryou have finished the maneuvering process
Ryou switch off the engine
For technical reasons, the flap may remain open briefly after the rear view camera has been
deactivated.
Switching the rear view camera on or
off
Driving systems161
Driving and parking
Z

This enables you to gain experience and get
used to the new handling characteristics.
RBefore 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
RAdjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
RIf the trailer is equipped with a separate func-
tional braking system, check before each
journey whether the brakes are functioning
correctly.
RSecure the load on the trailer according to the
applicable specifications and current stand-
ards on securing loads (
Ypage 246).
RWhen driving with a trailer, check at regular
intervals that the load is secured and that the
brakes and lights are working.
RBear in mind that the handling will be less
stable when towing a trailer than when driving
without one. Avoid sudden steering move-
ments.
RThe 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.
RIf possible, do not brake suddenly, but rather
moderately at first so that the trailer can acti-
vate its brakes. Then increase the force on the
brake pedal.
RIf 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.
RWhen 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 instal-
led, the trailer brakes.
RIf the coolant temperature increases dramat-
ically while the air-conditioning system is
switched on, switch off the air-conditioning
system.
Coolant heat can also be dissipated by
switching the airflow and the temperature of
the air conditioning to the
maximum level.
Open t

he windows if necessary.
RWhen overtaking, pay particular attention to
the extended length of your vehicle/trailer
combination.
Due to the length of your vehicle/trailer com-
bination you need an additional distance
before you can return to your original lane.
Uncoupling a trailer
GWARNING
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 rebounding of the overrun
brake.
XMake sure that the selector lever of the auto-
matic transmission is in position P.
XEngage the vehicle's parking brake.
XClose all doors.
XApply the parking brake of the trailer.
XIn addition, secure the trailer against rolling
away with a wheel chock or similar object.
XRemove the trailer cable and safety chains
and decouple the trailer.
168Towing a trailer
Driving and parking

Safety systems
Display messagesPossible causes/consequences andMSolutions
ABS,ESPInoperative
+
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.
GWARNING
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 brak-
ing 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.
XSwitch the engine off, wait briefly and start the engine again.
XCheck if the display message has disappeared and ESP®is opera-
tional.
XIf the display message continues to be displayed:
RDrive on with care.
RVisit 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.
GWARNING
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 brak-
ing 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.
XDrive on with care and on a suitable stretch of road make slight
steering movements at a speed above 12 mph (20 km/h).
XSwitch the engine off, wait briefly and start the engine again.
XCheck if the display message has disappeared and ESP®is opera-
tional.
XIf the display message continues to be displayed:
RDrive on with care.
RVisit a qualified specialist workshop immediately.
192Display messages (vehicles without steering wheel buttons)
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
÷
Inoperative+
ESP®,BA Sand hill start assist are unavailable due to amalfunction .
ATTENTION ASSIST is deactivated and other drivin gsystems could be
automatically deactivated.
GWARNIN G
The brak esystem continues to function normally, but without th e
function slisted above.
The braking distanc ein an emergenc ybraking situation can thus
increase.
If ES P
®is no toperational, ES P®will notstabiliz eth evehicle.
There is an increased ris kof skiddin gand accidents .
XSwitchth eengin eoff ,wait briefl yand start th eengin eagain .
XCheckif th edisplay message has disappeared and ES P®is opera-
tional.
XIf th edisplay message continues to be displayed:
RDrive on wit hcare.
RVisit aqualified specialist workshop immediately.
÷
Currently Unavail.
+
ES P®,BA Sand hill start assist are unavailable due to amalfunction .
The self-diagnosis function ,for example, may no tbe complete.
ATTENTION ASSIST is deactivated and other drivin gsystems could be
automatically deactivated.
GWARNIN G
The brak esystem continues to function normally, but without th e
function slisted above. The wheels could therefor eloc kif you brak e
hard, for example.
The braking distanc ein an emergenc ybraking situation can thus
increase.
If ES P
®is no toperational, ES P®will notstabiliz eth evehicle.
There is an increased ris kof skiddin gand accidents .
XDrive on withcar eon asuitable stretch of road, making mak eslight
steering movement sat aspeed abov e12 mph (20 km/ h).
If the display message disappears, the functions mentioned above
are available again.
XSwitch the engine off, wait briefly and start the engine again.
XCheck if the display message has disappeared and ESP®is opera-
tional.
XIf the display message continues to be displayed:
RDrive on with care.
RVisit a qualified specialist workshop immediately.
196Display messages (vehicles without steering wheel buttons)
On-board computer and displays

Engine
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
;NThe yellow Check Engine warning lamp lights up while the engine is running.
There may be a malfunction, for example:
Rin the engine management
Rin the transmission management
Rin the fuel injection system
Rin the exhaust system
Rin the ignition system (for vehicles with a gasoline engine)
Rin the fuel system
The emission limit values may be exceeded and the engine may be running in
emergency mode.
XHave the vehicle checked as soon as possible at a qualified specialist workshop.
æN The yellow reserve fuel warning lamp is on while the engine is running.
The fuel level has dropped to the reserve range.
XRefuel at the nearest gas station.
?N The red coolant warning lamp comes on while the engine is running.
On vehicles without steering wheel buttons, the coolant temperature gage is at the
start of the bar display (
Ypage 175).
On vehicles with steering wheel buttons, the coolant temperature gage is at the
start of the scale in the instrument cluster (
Ypage 39).
The temperature sensor for the coolant temperature gage is faulty.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
XStop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine. Do not continue driving under any circumstances.
XSecure the vehicle to prevent it from rolling away (Ypage 135).
XConsult a qualified specialist workshop.
Indicator and warning lamps in the instrument cluster227
On-board computer and displays
Z

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
XExit the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 255).
XIf you have to add coolant more frequently, have the engine cooling system
checked.
XMake sure that the air supply to the radiator is not obstructed, by frozen slush
for example.
XCheck the coolant temperature:
Rusing the display in the on-board computer on vehicles without steering wheel
buttons (Ypage 175)
Rusing the analog display in the instrument cluster on vehicles with steering
wheel buttons (Ypage 39)
XIf the coolant temperature is below the maximum value specified below, you can
continue driving to the nearest qualified specialist workshop.
Avoid heavy loads on the engine, e.g. driving in mountainous terrain, and stop-
start traffic.
Under normal operating conditions and with the specified coolant level, the cool-
ant temperature gage may rise to 248 ‡ (120 †).
Driving systems
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
·NThe red distance warning lamp lights up while the vehicle is in motion.
The distance to the vehicle in front is too small for the speed selected.
XIncrease the distance.
·N The red distance warning lamp lights up while the vehicle is in motion. An
additional warning tone sounds.
You are approaching a vehicle or a stationary obstacle in your line of travel at too
high a speed.
XBe prepared to brake immediately.
XPay particular attention to the traffic situation. You may have to brake or take
evasive action.
Further information about the distance warning function can be found under
"COLLISION PREVENTION ASSIST" (
Ypage 146).
Indicator and warning lamps in the instrument cluster229
On-board computer and displays
Z