2018 MERCEDES-BENZ A-CLASS SALOON warning

each time with
the conta cts onyour own
ve hicle firs t. #
Afterre moving the jump lead/charging
cable, close co ver1 of positive clamp 2.
Fu rther information can be obtained at a quali‐
fi ed specialist workshop. Re
placing the 12V battery #
Obser vethe no tes on the12 V battery
(/ page 455).
Mercedes-Benz recommends that you ha vethe
12 V battery replaced at a qualified specialist
wo rkshop, e.g. at a Mercedes-Benz Service
Centre.
Obser vethefo llowing no tes if youwa ntto
re place the battery yourself:
R Alw aysre place a faulty bat tery with a battery
which meets the specific vehicle requ ire‐
ments.
The vehicle is equipped with an AGMtech nol‐
ogy battery (Absorbent Glass Mat). Fullve hi‐ cle functionality is only guaranteed with an
AG M batter y.Fo r saf etyre asons, Mercedes-
Benz recommends that you on lyuse bat ter‐
ies which have been tested and appr ovedfor
yo ur vehicle byMercedes-Benz.
R Carryove r de tach able parts, such as vent
hoses, elbow fittings or term inal co vers from
th e battery being replaced.
R Make sure that theve nt hose is al ways con‐
nected tothe original opening on the side of
th e batter y.
Fit any existing or supplied cell caps.
Otherwise, gases or battery acid could
escape.
R Make sure that de tach able parts are recon‐
nected in the same way. To
w- starting or towing away Pe
rm itted towing me thods Mercedes-Benz
recommends transporting your
ve hicle in the case of a breakdown, rath er than
to wing it away. Fo
rto wing, use a tow rope or tow bar with bo th
axles on the ground. Do not use tow bar sys‐
te ms. &
WARNING Risk of accident when towing
with steering wheel lock
Yo u will no lon ger be able tosteer theve hicle
if th esteering wheel lock is engaged. #
Alw ays switch on the ignition when tow‐
ing theve hicle with a tow cable or a tow
bar. *
NO
TEDama getotheve hicle due to tow‐
ing away incor rectly #
Obser vethe instructions and no tes on
to wing away. 460
Breakdown assis tance

*
NO
TEDama gedue to to wing away at
exc essively high speeds or over long dis‐
ta nces The driv
etra in could be damaged when tow‐
ing at excessively high speeds or over long
dis tances. #
Atowing speed of 50 km/h must not
be exc eeded. #
Atowing dis tance of 50 km must not be
exc eeded. &
WARNING Risk of accident when towing
a ve hicle which is too heavy
If th eve hicle being tow- star ted or towed
aw ay is heavier than the permissible gross
mass, thefo llowing situations can occur:
R theto wing eye may become de tach ed.
R the car/t railer combination may swer ve
or eve nove rturn. #
If ano ther vehicle is tow- star ted or
to we daw ay, its weight must not exceed th
e permissible gross mass of your own
ve hicle. If a
vehicle must be tow star ted or towe daw ay,
its permissible gross mass must not exceed the
permissible gross mass of theto wing vehicle. #
Information on the permissible gross mass of
th eve hicle can be found on theve hicle iden‐
tification plate (/ page 494). #
Vehicles with automatic transmission: do
not open the driver's door or front passenger
door, otherwise the automatic transmission
automatically shifts toposition j. #
Fittheto wing eye (/ page 464). #
Fasten theto w bar.
* NO
TEDama gedue toincor rect connec‐
tion #
Only connect theto w rope or tow bar to
th eto wing eyes. #
Deactivate the automatic locking mechanism
(/ page81). #
Do not activate the HOLD function. #
Deactivate tow- aw ay protection
(/ page 95). #
Deactivate Active Brake Assi st
( / page 201). #
Vehicles with automatic transmission:
shift the automatic transmission toposition
i. #
Vehicles with manual transmission: shift
to neutral i. #
Release the electric parking brake. #
Switch on the ignition, otherwise thesteering
wheel lock may engage. &
WARNING Risk of accident due tolimi‐
te d saf ety-re lated functions during the
to wing process
Saf ety-re lated functions are limited or no lon‐
ge rav ailable in thefo llowing situations:
R the ignition is switched off. 462
Breakdown assis tance

#
Vehicles with automatic transmission
must not be tow- star ted. #
Vehicles with automatic transmission must
not be tow- star ted.
Ve hicles with manual transmission #
Obser vethe no tes on towing away
( / page 461). #
If necessar y,allow the engine and exhaust
sy stem tocool down. #
Switch the ignition on. #
Enga gesecond gear. #
Release the electric parking brake. #
Tow- start theve hicle while the clutch pedal
is fully depressed. #
Slowly release the clutch pedal. #
Immediately shift toneutral if the engine
st arts. #
Pull over and stop theve hicle, paying atten‐
tion toroad and traf fic conditions. #
Remo vetheto w bar. #
Remo vetheto wing eye. #
Have theve hicle checked at a qualified spe‐
cialist workshop. Electrical fuses
Note
s on electrical fuses &
WARNING Risk of accident and inju ry
due to ov erloaded lines
If yo u manipulate or bridge a faulty fuse or if
yo ure place it with a fuse with a higher
amperage, the electric line could be overloa‐
ded.
This could result in a fire. #
Alw aysre place faulty fuses with speci‐
fi ed new fuses conta iningthe cor rect
amperage. *
NO
TEDama gedue toincor rect fuses Electrical components or sy
stems may be
damaged byincor rect fuses, or their func‐
tionality may be significant lyimpaired. #
Only use fuses that ha vebeen appr oved
by Mercedes-Benz and which ha vethe
cor rect fuse rating. Blown fuses mu
stbe replaced with fuses of the
same rating, which you can recognise bythe col‐
our and fuse rating. The fuse ratings and fu rther
information tobe obser ved are lis ted in the fuse
assignment diagram.
Fu se assignment diag ram: onthe fuse box in
th e engine compartment (/ page 466).
* NO
TEDama geor malfunctions caused
by moisture Moisture may cause dama
getothe electrical
sy stem or cause it tomalfunction. #
When the fuse box is open, make sure
th at no moisture can enter the fuse
box. #
When closing the fuse box, make sure
th at the seal of the lid is positioned cor‐
re ctly on the fuse box. Breakdown assis
tance 465

If
th e newly inser ted fuse also blo ws, ha vethe
cause traced and rectified at a qualified special‐
ist workshop.
Ensure thefo llowing before replacing a fuse:
R The vehicle is secured against rolling away
R All electrical consumers are switched off
R The ignition is switched off
The electrical fuses are located in various fuse
bo xes:
R Fuse box in the engine compartment on the
left-hand side of theve hicle, when vie wed in
th e direction of tr avel (/ page 466)
R Fuse box in the front passenger foot we ll
(/ page 467)
R Fuse box in the cent reofthe boot
(/ page 468) Opening and closing
the fuse box in the
engine compa rtment Re
quirements:
R A dry clo thand a sc rewdriver are available. Obse
rveth e no tes on electrical fuses
(/ page 465).
Opening &
WARNING Risk of inju ryfrom using the
windscreen wipers while the engine bon‐
net is open
When the engine bonn etis open, and the
windscreen wipers are set in motion, you can
be trapped bythe wiper linkage. #
Alw ays switch off the windscreen wip‐
ers and ignition before opening the
engine bonn et. #
Open the bonn et. #
Remo veany existing moisture from the fuse
box using a dry clo th. #
Loosen scr ews1. #
Press clamps 2and lift the fuse box lid up
and out.
The fuse allocation chart is in a recess on the
side of the fuse box. 466
Breakdown assis tance

Note
s on noise or unusual handling charac‐
te rist ics
While driving, pay attention tovibrations, noises
and unusual handling characteristics, e.g. pulling
to one side. This may indicate that the wheels or
tyres are damaged. If you suspect that a tyre is
defective, reduce your speed immediatel y.Stop
th eve hicle as soon as possible tocheck the
wheels and tyres for dama ge. Hidden tyre dam‐
age could also be causing the unusual handling
ch aracteristics. If youfind no signs of damage,
ha ve the tyres and wheels checked at a qualified
specialist workshop. Note
s onregular lyinspecting wheels and
tyres &
WARNING Risk of accident from dam‐
aged tyres
Dama ged tyres can cause tyre pressure loss.
As a result, you could lose cont rol of your
ve hicle. #
Check the tyres regularly for signs of
dama geand replace any damaged tyres
immediatel y. Car
ryout thefo llowing checks on all wheels reg‐
ularly, at least once a month or as requ ired, e.g.
prior toa long journey or driving off- road:
R Check the tyre pressure (/ page470).
R Visually inspect tyres and wheels for dam‐
age.
R Check theva lve caps.
The valves must be pr otected against mois‐
ture and dirt bytheva lve caps appr oved
especially foryo ur vehicle byMercedes-Benz.
R Visual check of the tyre tread dep thand the
tyre contact su rface across the entire width.
The minimum tread dep thfor summer tyres
is 3 mm and for winter tyres 4 mm. Note
s on snow chains &
WARNING Risk of accident due toincor‐
re ct snow chain fitting
If yo ufit snow chains tothere ar wheels, the
snow chains may grind against theve hicle
body or chassis components.
This could cause damage totheve hicle or
th e tyres. #
Neverfit snow chains tothere ar
wheels. #
Alw aysfit snow chains tothe front
wheels in pairs. *
NO
TEDama getothe wheel trim from fit‐
te d snow chains If sn
ow ch ains are fitted tosteel wheels, the
wheel trims can be damaged. #
Remo vethe wheel trims of steel wheels
before fitting snow chains. Wheels and tyres
469

Obser
vethefo llowing no tes when using snow
ch ains:
R Snow ch ains are on ly permissible for cer tain
wheel/tyre combinations. You can obtain
information about this from a Mercedes-Benz
Service Cent re.
R For saf etyre asons, on lyuse sn ow chainsthat
ha ve been specifically appr ovedfo ryo ur
ve hicle byMercedes-Benz, or snow chains
with the same quality standard.
R If sn ow ch ains are fitted, the maximum per‐
missible speed is 50 km/h.
R Vehicles with Active Park ing Assis t:do
not use Active Parking Assist when snow
ch ains are fitted.
% You can permanently limit the maximum
ve hicle speed for driving with winter tyres
(/ page 205).
% You can deactivate ESP ®
to pull away
( / page194). This allo ws the wheels to
spin, achieving an increased driving forc e. Ty
re pressure Note
s on tyre pressure &
WARNING Risk of accident due toinsuf‐
fi cient or excessive tyre pressure
Underinfla ted or overinfla ted tyres pose the
fo llowing risks:
R The tyres may bur st, especially as the
load and vehicle speed increase.
R The tyres may wearexc essively and/or
une venly, which may greatlyimpair tyre
traction.
R The driving characteristics, as well as
st eering and braking, may be greatly
impaired. #
Comply with there commended tyre
pressure and check the tyre pressure of
all tyres including the spare wheel regu‐
larly:
R at least once a month
R when the load changes R
before embarking on a lon ger journey
R if operating conditions change, e.g. off-
ro ad driving #
Adjust the tyre pressure as necessar y. Driving wi
thtyre pressu rethat is too high or too
low can:
R Sho rten the service life of the tyres.
R Cause increased tyre damage.
R Adversely af fect driving characteristics and
th us driving saf ety, e.g. due toaquaplaning. &
WARNING Risk of accident from repea‐
te d tyre pressure drop
If th e tyre pressure drops repeatedl y,the
wheel, valve or tyre may be damaged.
Insuf ficient tyre pressure can cause the tyres
to bur st. #
Inspect the tyre for signs of fore ign
objects. 47 0
Wheels and tyres

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 (/ page470) 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
(/ page472).
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 (/ page545)
R viatheh warning lamp in the instrument
clus ter (/ page571)
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
ta ught-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 (/ page473). 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 (/ page470)
Checking the ty repressure with the tyre
pressure moni toring sy stem
Re quirements:
R The ignition is switched on.
On-board computer: 4 Service 5
Tyres
One of thefo llowing displa ysappears:
R Cur rent tyre pressure and tyre temp erature
of the individual wheels: 472
Wheels and tyres

R
Tyre pressures will be displayed after a few
minutes of driving
R Tyre pressure monitor active: thete ach-in
process of the sy stem is not yet compl ete.
The tyre pressures are already being moni‐
to re d. #
Compare the tyre pressure with there com‐
mended tyre pressure forth e cur rent operat‐
ing condition (/ page 471). Obse rvethe
no tes on tyre temp erature (/ page470).
% The values displa yed in the multifunction dis‐
play may deviate from those of the tyre pres‐
sure gauge as they referto sea le vel.At high
altitudes, the tyre pressure values indicated by
a pressure gauge are higher than those
shown bythe on-board computer. In this
case, do not reduce the tyre pressure.
Make sure toobser vethefo llowing fur ther rela‐
te d subjec t:
R Notes on tyre pressure (/ page470)
Re starting the ty repressure moni toring sys‐
tem
Re quirements:
R The recommended tyre pressure is cor rectly
set forth ere spective operating status on
each of thefo ur wheels (/ page470).
Re start the tyre pressure monitoring sy stem in
th efo llowing situations:
R The tyre pressure has changed.
R The wheels or tyres ha vebeen changed or
newly fitted. On-boa
rdcompu ter:
4 Service 5
Tyres #
Swipe down wards on Touch Control on the
left-hand side of thesteering wheel.
The Use current pressures as new reference
values? message is shown in the multifunc‐
tion displa y. #
Tobegin restart, press Touch Control on the
left-hand side of thesteering wheel.
The Tyre press. monitor restarted message is
shown in the multifunction displa y.
Cur rent wa rning messages are dele ted and
th eye llow h warning lamp goes out.
Af teryo u ha vebeen driving for a few
minutes, the sy stem checks whe ther the cur‐
re nt tyre pressures are wi thin the specified
ra nge. The cur rent tyre pressures are then
accep ted as refere nce values and monitored.
Make sure toobser vethefo llowing fur ther rela‐
te d subjec t:
R Notes on tyre pressure (/ page470) Wheels and tyres
473