warning light MERCEDES-BENZ A-CLASS HATCHBACK 2018 Workshop Manual

#
Remo vethe co ver from the ball head and
st ore it in a safe place.
Make sure that the ball of the ball neck is clean.
Check that it is either greased or dr y (grease
free), depending on the instructions forthe
traile r.
Fo lding the ball neck in #
Pull release switch 2until the ball neck
unloc ks.
The ball neck folds up under there ar
bumper.
Indicator lamp 1flashes. #
Push the ball neck in the direction of the
ar row until it en gage s audibly behind the
bumper.
Indicator lamp 1goes out and the message
on the multifunction display disappears.
Obser vethe information on the displa yson the
instrument clus ter:
R Warning and indicator lamps (→ page548)
R Displ aymessa ges (→ page 498) Coupling up/uncoupling a trailer
Re
quirements:
R the ball neck must be extended and engaged
in the securely loc ked position
Tr ailers with a 7-pin plug can be connec tedto
th eve hicle with thefo llowing adap ters:
R adap ter plug
R adapte r cable
The trailer will be cor rectly de tected bytheve hi‐
cle only if thefo llowing conditions are me t:
R the trailer is connected cor rectly
R the trailer lighting sy stem is in working order
The functions of thefo llowing sy stems are af fec‐
te dby a cor rectly connected traile r:
R Active Lane Keeping Assist
R ESP ®
trailer stabilisation
R Parking Assist PARKTRONIC
R Active Parking Assist
R Blind Spot Assist or Active Blind Spot Assi stCoupling up a trailer
* NO
TEDama getotheve hicle battery due
to full dischar ge Charging
the trailer battery using the po wer
supply of the trailer can damage theve hicle
batter y. #
Do not use theve hicle's po wer supply
to charge the trailer batter y. #
Remo vethe co ver from the ball head and
st ore it in a safe place (→ page101). #
Position the trailer on a le vel sur face behind
th eve hicle and couple it up totheve hicle. 244
Driving and pa rking

#
Open the soc ket cap. #
Inse rtthe plug with lug 1in groo ve3 on
th e soc ket. #
Turn bayonet coupling 2clockwise as far as
it will go. #
Let the cap engage. #
Secure the cable tothe trailer with cable ties
(only if you are using an adap ter cable). #
Make sure that the cable is alw ays slack for
ease of mo vement during cornering.
A display messa gemay appear on the multifunc‐
tion display even if the trailer has been connec‐
te d cor rectly:
R LEDs ha vebeen ins talled in the trailer light‐
ing sy stem
R The cur rent has fallen below the trailer light‐
ing sy stem's minimum cur rent (50 mA).
% Accessories can be connected tothe perma‐
nent po wer supp lyup to180W, and tothe
po we r supp lythat is swit ched on via the igni‐
tion loc k. Un
coupling a trailer &
WARNING Risk of being crushed and
becoming trapped when uncoupling a
trailer
When uncoupling a trailer wi than engaged
ine rtia-activated brake, your hand may
become trapped between theve hicle and the
trailer dr awbar. #
Do not uncouple trailers with an
engaged overrun brake. #
Secu rethe trailer against rolling away. #
Disconnect the electrical connection
between theve hicle and the trailer. #
Uncouple the trailer. #
Place the co ver on the ball head. Bicycle
rackfunction &
WARNING Risk of an accident when
using the bicycle rack incor rectly
The bicycle rack may become de tach ed from
th eve hicle in thefo llowing cases:
R the permissible load capacity of the
trailer hitch is exceeded.
R the bicycle rack is used incor rectl y.
R the bicycle rack is secured tothe ball
neck beneath the ball head.
Obser vethefo llowing foryo ur ow n sa fety
and that of other road users: #
always adhere tothe permissible load
capacity of the trailer hitch. #
only use the bicycle rack totranspo rt
bicycles. #
always proper lysecure the bicycle rack
by attaching it tothe ball head. #
only use bicycle rack s appr ovedby
Mercedes-Benz. Driving and parking
245

#
Turn brightness control 1up or down.
The lighting of the instrument display and in
th e control elements of theve hicle interior is
adjus ted. Menus and submenus
Fu
nctions on the service menu of the on-
board compu terOn-board computer:
, Service #
Toselect the function: swipe upwards or
down wards on the left-hand Touch Control. #
Press the left-hand Touch Control.
Fu nctions on theService menu:
R Message memory (→ page 498)
R AdBlue :Ad blue ®
ra nge and fill le vel
R Tyres:
- Restart the tyre pressure loss warning
sy stem (→ page 467) -
Check the tyre pressure with the tyre
pressure monitoring sy stem
(→ page 461)
- Restart the tyre pressure monitoring sys‐
te m (→ page 462)
R ASSYST PLUS : calls upthe service due date
(→ page 419)
R Coolant: coolant temp erature display
R Engine oil level: engine oil le vel
R Consumption info: fuel life cycle consump‐
tion Calling up
the assistant display On-board computer:
, Assistance
The following displa ysare available on the assis‐
ta nt displ aymenu:
R Assis tant displ ay
R Attention le vel (→ page 231)
R Full-sur face menu displ ay #
Toswitch between the displa ys:swipe
upwards or down wards on the left-hand
To uch Control. St
atus displa yson the assis tant displ ay:
R é ATTENTION ASSIS T:deactivated
R ¸ Grey radar waves next tovehicle: Blind
Spot Assist or Active Blind Spot Assi stena‐
bled
R ¸ Green radar waves next tovehicle:
Blind Spot Assist or Active Blind Spot Assi st
active
R DISTRO NICActive Dis tance Assi stdispla ys
( → page 200) 254
Instrument Display and on-board computer

Selecting what
the head-up display sho ws(Example)
R 1 Switches the head-up display on/off
2 Display area left
- Navigation sy stem
- Average consum ption
- G-me ter
R 3 Displ ayarea centre
- Set speed in the driver assis tance sy stem
(e.g. cruise control)
- Warnings from driver assis tance sy stems
(e.g. dis tance warning) R
4 Display area right
- Traf fic Sign Assi st
- Assi stant display
R 5 Selects the settings
R 6 Index points
Non- requ ired display areas 2to4 can be hid‐
den.
% In audio mode, thest ation name or track will
be shown temp orarily when the audio source
is being actively operated. #
Toselect a displa y:swipe upwards or down‐
wa rds on the left-hand Touch Control. #
Press the left-hand Touch Control. Head-up Display
Fu
nction of the head-up display The head-up display projects impor
tant informa‐
tion in the driver's field of vision, e.g. cur rent
speed. Depending on
theve hicle's equipment, dif fere nt
content can be shown in theth re e display areas
of the head-up display (→ page 259).
Sy stem limitations
The visibility of the displa ysis af fected bythe
fo llowing conditions:
R seat position
R positioning of the display image
R light conditions
R wet car riag ewa ys
R objects on the display co ver
R polarisation in sunglasses
% Inextreme sunlight, sections of the display
may appear washed out. You can co rrect this
by deactivating and reactivating the head-up
displa y. 260
Instrument Display and on-board computer

AG
. The da taisthen immediately pseudony‐
mised byDaimler AG. The vehicle data is dele ted
af te r an appro priate amount of time has elapsed
(se veralwe eks) and is not stored permanent ly.
% Data which ser ves as identification is
re placed during the pseudonymisation proc‐
ess. In this wa y,yo ur identity is pr otected
against access byunauthorised third parties.
Displaying hazard warnings
Multimedia sy stem:
, © #
Select Navigation (Navigation).
If hazard warnings are available these will be
shown on the map.
The following hazard warnings are shown on the
map:
R broken-down vehicles
R accidents
R hazardous weather
R general hazards
R hazard warning lights, if activated
R mobile roadwor ks The display is not
available in all countries
and regions.
In theFe deral Republic of Germany the dis‐
play is cur rently available in theFe deral State
of Hesse.
% Ifth eve hicle is approaching a hazard spot
with a vehicle speed of at least 60 km/h, the
vo ice output "T raffic incident ahead" is
issued.
The voice output is not issued for hazardous
we ather.
Sending haza rdwa rnings
Au tomatically de tected hazard warnings are sent
by theve hicle. #
Tosend a haza rdwa rning yourself: tap on
th e media display when the map is shown.
The navigation menu is shown. #
Select ¡. #
Select Report traffic incident.
A prom ptis shown. #
Select Yes.
The Thank you for supporting accident pre-
vention. message appears. Ro
ute guidance with augmented reality Overview of
route guidance with augmented
re ality &
WARNING Risk of accident and inju ry
caused bydistraction, inco rrect image or
interpr etation of the display
The dis tance to ot herroad users or informa‐
tion, such as traf fic lights, can be incor rectly
assessed from the camera image. The cam‐
era image of the augmented reality display is
not suitable tobe used for driving. #
Alw ayske ep your eyes on the actual
tra ffic situation. Only glance brief lyat
th e camera image. #
Beaware that depending on the driving
situation there may be hazards that are
not captured in the camera image, e.g.
when turning. Avoid observing the cam‐
era image forex tended pe riods. During
route guidance with augmented reality a
camera image with there al traf fic scene is 354
MBUX multimedia sy stem

#
With your hand flat, push down active bonnet
1 inthe area around the hinges on bo th
sides (ar rows).
In doing so, the actuator is depressurised
and you may hear a hissing sound.
The engine bonnet must en gage in position. #
Ifth e active bonn etcan be raised slight lyat
th ere ar in the area of the hinges, repeat the
st ep until it engages cor rectl y. Opening/closing
the bonnet &
WARNING Risk of accident due todriv‐
ing with the engine bonn etunlo cked
An unloc ked engine bonn etmay open up
when theve hicle is in motion and block your
vie w. #
Never unlock the engine bonn etwhen
driving. #
Before every trip, ensure that the
engine bonn etis loc ked. &
WARNING Risk of accident and inju ry
when opening and closing the engine
bonn et
When opening or closing the engine bonn et,
it may suddenly drop into the end position.
There is a risk of injury for an yone in the
engine bonn et's range of mo vement. #
Only open or close the engine bonn et
when there are no persons in the
engine bonn et's range of mo vement. &
WARNING Danger of bu rns when open‐
ing the bonn et
If yo u open the engine bonn etwhen the
engine has overheated or during a fire inthe
engine compartment, you could come into
contact with hot gases or other escaping
operating fluids. #
Before opening the bonn et, allow the
engine tocool down. #
Intheeve nt of a fire inthe engine com‐
partment, keep the engine bonn et
closed and call thefire service. &
WARNING Risk of inju rydue tomoving
parts
Cer tain components in the engine compart‐
ment may continue tomo veor suddenly
mo veagain even af terth e ignition has been
switched off, e.g. the cooler fan.
Ma kesure of thefo llowing before per form ing
ta sks in the engine compartmen t: #
Switch the ignition off. Maintenance and care
421

Note
s on care of the interior &
WARNING Risk of inju ryfrom pla stic
parts breaking off af terth e use of sol‐
ve nt-based care products
Ca reand cleaning products con taining sol‐
ve nts can cause su rfaces in the cockpit to
become porous. When
the airbags are deplo yed, plastic parts
may break away. #
Do not use any care or cleaning prod‐
ucts containing sol vents toclean the
cockpit. &
WARNING Risk of inju ryor death from
bleached seat belts
Bleaching or dyeing seat belts can se verely
we aken them.
This can, forex ample, cause seat belts to
te ar or fail in an accident. #
Never blea chor dye seat belts. Obser
vethefo llowing information: Cleaning and car
eA voiding vehicle damage
Seat belts Clean with lukewarmand soapy water. R
Do not use chemical cleaning agents.
R Do not dry seat belts byheating them toove r 80 °C or
ex posing them todirect sunlight.
Display Cleanthe sur face carefully wi tha mic rofibre clo thand a suit‐
able display care product (TFT LCD). R
Switch off the display and let it cool down.
R Do not use any other cleaning products.
Plastic trim R
Clean with a damp microfibre clo th.
R For heavy soiling: use care product recommended for
Mercedes-Benz. R
Do not attach sticke rs,fi lms or similar materials.
R Do not allow cosmetics, insect repellent or sun cream to
come in contact wi th the plastic trim. 434
Maintenance and care

#
Cor rect the tyre pressure if it is still at least
13 0 kPa (1.3 bar/19 psi). See the tyre pres‐
sure table on the fuel filler flap forva lues. #
Toincrease the ty repressure: switch on
th e tyre inflation compressor. #
Toreduce the tyre pressure: press pres‐
su re re lease button 1next tomanome ter
2 . #
When the tyre pressure is cor rect, unscr ew
th efilling hose from theva lve of the sealed
tyre. #
Screw theva lve cap onto theva lve of the
sealed tyre. #
Pull the tyre sealant bottle out of the tyre
inflation compressor.
The filling hose stay s on the tyre sealant bot‐
tle. #
Drive tothe nearest qualified specialist work‐
shop and ha vethe tyre, tyre sealant bottle
and filling hose replaced there. Batte
ry(vehicle) Note
s onthe12 V battery &
WARNING Risk of an accident due to
wo rkcar ried out incor rectly on the bat‐
te ry
Wo rkcar ried out incor rectly on the battery
can, forex ample, lead toa short circuit. This
can lead tofunction restrictions in saf ety-re l‐
eva nt sy stems, e.g. the lighting sy stem, ABS
(anti-lock braking sy stem) or ESP ®
(Elec‐
tronic Stability Prog ram). The operating
saf ety of your vehicle may be restricted. Yo
u could lose cont rol of theve hicle in the
fo llowing situations:
R when braking
R intheeve nt of ab rupt steering manoeu‐
vres and/or when theve hicle's speed is
not adap tedto thero ad conditions #
Intheeve nt of a sho rtcircuit or a simi‐
lar incident, contact a qualified special‐
ist workshop immediately. #
Do not continue driving. #
Alw ays ha vewo rkon the battery car ried
out at a qualified specialist workshop. R
Further information on ABS (→ page185)
R Further information on ESP ®
(→ page 186)
Fo r saf etyre asons, Mercedes-Benz recommends
th at you on lyuse bat teries which ha vebeen tes‐
te d and appr ovedfo ryo ur vehicle byMercedes-
Benz. These batteries pr ovide inc reased impact
pr otection toprev ent vehicle occupants from
suf fering acid bu rns should the battery be dam‐
aged in theeve nt of an accident. 444
Breakdown assis tance

&
WARNING Risk ofexplosion from a fro‐
zen battery
A dischar ged battery may freeze at temp era‐
tures slightly abo veor below freezing point.
During starting assis tance or battery charg‐
ing, bat tery gas may be released. #
Alw aysth aw a frozen bat tery out first
before charging it or per form ing start‐
ing assis tance. If
th e indicator/warning lamps in the instrument
clus ter do not light up at low temp eratures, it is
ve ry likely that the dischar ged battery has fro‐
zen. In this case you may neither jump-s tart the
ve hicle nor charge the batter y.
The service life of a battery that has been
th awe d may be dramatically shor tened. The
st arting characteristics may be impaired, espe‐
cially at low temp eratures.
It is recommended that you ha veathaw ed bat‐
te ry checked at a qualified specialist workshop. *
NO
TEDama gecaused bynumerous or
ex tended attem ptsto start the engine Nume
rous or extended attem ptsto start the
engine may damage the catalytic con verter
due tonon-combu sted fuel. #
Avoid numerous and extended attem pts
to start the engine. Obser
vethefo llowing points during starting
assis tance and when charging the battery:
R Only use undamaged jump lead/charging
cables with a suf ficient cross-section and
insula tedte rm inal clamps.
R Non- insulated parts of thete rm inal clamps
must not come into con tact wi thother me tal
parts while the jump lead/charging cable is
connected tothe battery/jump-s tart connec‐
tion point.
R The jump lead/charging cable must not
come into contact wi thany parts which may
mo vewhen the engine is running.
R Alw ays make sure that nei ther you nor the
battery is elect rostatically charge d. R
Keep away from fire and naked flames.
R Do not lean overth e batter y.
Obser vethe additional following points when
ch arging the battery:
R Only use battery charge rs tested and
appr oved for Mercedes-Benz.
R Read the battery charge r's operating instruc‐
tions before charging the batter y.
Obser vethe additional following points during
st arting assis tance:
R Starting assis tance may only be pr ovided
using batteries with a nominal voltage of 12
V.
R The vehicles must not touch.
R Petrol engine: only acceptstarting assis‐
ta nce if the engine and exhaust sy stem are
cold. Breakdown assis
tance 447

If
th e preceding tyre sizes are complemented by
th e+ symbol, the tyre pressure information
fo llowing sho wsalternative tyre pressures.
These tyre pressures may impr oveyour vehicle's
ri de comfort. Fuel consum ption may then
increase slightl y.
The load conditions "partially laden" and "fully
laden" are defined in theta ble for dif fere nt num‐
be rs of passengers and amounts of luggage. The
actual number of seats may dif fer from this.
Be sure toalso obse rveth efo llowing fur ther
re lated subjects:
R Notes on tyre pressure (→ page 459)Ty
re pressure moni toring sy stem Fu
nction of the ty repressure moni toring sys‐
tem
The sy stem checks the tyre pressure and the
tyre temp erature of the tyres fitted totheve hicle
by means of a tyre pressu resensor.
New tyre pressure sensors, e.g. in winter tyres,
are automatically taught-in during thefirs t jour‐
ney they are used. The tyre pressure and
the tyre temp erature
appear in the multifunction display
(→ page 461).
If th ere is a subs tantial pressure loss or if the
tyre temp erature is excessive, you will be
wa rned in thefo llowing ways:
R via display messa ges (→ page 528)
R viatheh warning lamp in the instrument
clus ter (→ page 559)
The tyre pressu remonitoring sy stem is only an
aid. It is the driver's responsibility toset the tyre
pressure tothere commended cold tyre pressure
suitable forth e operating situation. Set the tyre
pressure for cold tyres using a tyre pressu re
ga uge. Notethat the cor rect tyre pressure for
th e cur rent operating situation mu stfirs t be
tau ght-in tothe tyre pressure monitoring sys‐
te m.
In most cases, the tyre pressure monitoring sys‐
te m will auto matically update the new refere nce
va lues af teryo u ha vechanged the tyre pressure.
Yo u can, ho wever,also update there fere nce val‐
ues byrestarting the tyre pressure monitoring
sy stem manually (→ page 462). Sy
stem limitations
The sy stem may be impaired or may not function
in thefo llowing situations:
R ifth e tyre pressure is set incor rectly
R ifth ere is a sudden pressure loss caused, for
ex ample, byafo re ign object penetrating the
tyre
R ifth ere is a malfunction caused byano ther
ra dio signal source
Make sure toobser vethefo llowing fur ther rela‐
te d subjec t:
R notes on tyre pressure (→ page 459)
Checking the ty repressure with the tyre
pressure moni toring sy stem
Requ irements:
R The ignition is switched on.
On-board computer: , Service .
Tyres
One of thefo llowing displa ysappears:
R Cur rent tyre pressure and tyre temp erature
of the individual wheels: Wheels and tyres
461