sensor MERCEDES-BENZ A-CLASS SALOON 2021 Owner's Guide

Ext
Ext
er
erior lighting
ior lighting
R Clean the lenses with a wet sponge and mild
cleaning agent, e.g. car sha mpoo.
R Only use cleaning agents or cleaning clo ths
th at are suitable for plastic lenses.
V
V ehicle soc ke
ehicle soc ket (high-v
t (high-v olt
oltag
age batt
e batt er
ery)
y)
R Use clean water and a soT clo thtoclean the
ve hicle soc ket.
R Do not use high-pressure cleaners or cleaning
agents, such as soap.
Sensors
Sensors
R Clean the sensors in the front and rear bump-
ers with a soT clo thand car shampoo
(/ page 214).
R When using a high-pressure cleaner, main tain
a minimum distance of 30 cm.
Rev Rev er
ersing camer
sing camer a and 360° Camera
a and 360° Camera
R Open the camera co ver with the multimedia
system (/ page 254).
R Use clean water and a soT clo thtoclean the
camera lens.
R Do not use a high-pressure cleane r.T
T
ailpipes
ailpipes
R Clean with a cleaning agent recommended for
Mercedes-Benz, especially in the winter and
aTer washing theve hicle.
R Do not use acidic cleaning agents.
Tr
Tr ailer hitch
ailer hitch
R Obser vethe no tes on care in the trailer hitch
manufacturer's operator manual.
R Do not clean the ball neck with a high-pres-
sure cleaner or sol vent.
R Remo vetraces of rust on the ball, forex ample,
with a wire brush.
R Remo vedirt with a lint-free clo th.
R ATer cleaning, lightly oil or grease the ball
head.
% Before using trailers with anti-torsional cou-
pling, obser vethe manufacturer's operator
manual. N No
ot
tes on car
es on car e of t
e of t he int
he int er
erior
ior &
W
WARNING
ARNING Risk of injury from plastic parts
breaking o. aTer the use of sol vent-based
ca re products
Care and cleaning products containing sol-
ve nts can cause sur faces in the cockpit to
become porous. When the airbags are
deplo yed, plastic parts may break away. #
Do not use any care or cleaning products
containing sol vents toclean the cockpit. &
W WARNING
ARNING Risk of injury or fatal injuries
from bleached seat belts
Bleaching or dyeing seat belts can se verely
we aken them.
This can, forex ample, cause seat belts to tear
or fail in an accident. #
Never bleach or dye seat belts. To
avo id damage totheve hicle, obser vethefo l-
lowing no tes on cleaning and care: Main
tenance and ca re
337
337

If one or more tyre sizes precede a tyre pressure,
th efo llowing tyre pressure information is only
va lid forth ose tyre sizes and their respecti veload
condition.
If th e preceding tyre sizes are complemented by
th e+ symbol, the tyre pressure information
fo llowing sho wsalternative tyre pressures. Fuel
consum ption may then increase slightl y.
The load conditions "pa rtially laden" and "fully
laden" are de/ned in theta ble for di.erent num-
bers of passengers and amounts of luggage. The
actual number of seats may di.er from this. T T
yr
yr e pr
e pr essur
essur e monit
e monit or
oring syst
ing syst em
em F
F
unction of t
unction of t he tyr
he tyre pr
e pressur
essur e monit
e monit or
oring syst
ing syst em
em
The system checks the tyre pressure and the tyre
te mp erature of the tyres /t tedtotheve hicle by
means of a tyre pressure sensor.
The tyre pressure and the tyre temp erature
appear in the on-board computer (/ page 366).
If th ere is a substantial pressure loss or if the tyre
te mp erature is excessive, you will be warned with
display messages (/ page 458) ortheh wa
rning lamp in the inst rument cluster
(/ page 482).
The tyre pressure monitoring system is only an
aid. It is the driver's responsibility toset the tyre
pressure tothere commended cold tyre pressure
suitable forth e operating situation.
In most cases, the tyre pressure monitoring sys-
te m will automatically update the new refere nce
va lues aTer you ha vechanged the tyre pressure.
Yo u can, ho wever, also update there fere nce val-
ues byrestarting the tyre pressure monitoring
system manually (/ page 367).
Syst
Syst em limits em limits
The system may be impaired or may not function
particular lyin thefo llowing situations:
R incor rect refere nce values were ta ught in
R sudden pressure loss caused byafo re ign
object penetrating the tyre, forex ample
R there is a malfunction caused byano ther radio
signal source Chec
Chec king t
king t he tyr
he tyr e pr
e pressur
essur e wit
e with t
h the tyr
he tyr e pr
e pressure
essure
monit
monit or
oring sy
ing sy st
stem
em
R
R eq
eq uir
uir ements:
ements:
R The vehicle is switched on.
On-board computer: 4 Service 5
Tyres
One of thefo llowing displa ysappears:
R Current tyre pressure and tyre temp erature of
th e individual wheels: R
Tyre pressures will be displayed after a few
minutes of driving 366 366
Wheels and tyres

R
Furthermore, the use of cer tain tyre types in
cer tain regions and areas of operation can be
high lybene/cial.
R Only use tyres and wheels of the same type
(summer tyres, winter tyres, MOExtended
tyres) and the same make.
R Only /t wheels of the same size on one axle
(leT and right).
It is only permissible to/t a di.e rent wheel
size in theev ent of a 0at tyre in order todrive
to the specialist workshop.
R Do not make any modi/cations tothe brake
system, the wheels or the tyres.
The use of shims or brake dust shields is not
permitted and may in validate theve hicle's
ge neral ope rating permit.
R V
V ehicles wit ehicles wit h a tyr
h a tyre pr
e pressur
essur e monit
e monit or
oring sy
ing sy s-
s-
t
t em:
em: all /t tedwheels must be equipped with
functioning sensors forth e tyre pressure mon-
itoring system.
R Attemp eratures below 7 °C use winter tyres
or all-season tyres mar kedi M+Sfor all
wheels. Wi
nter tyres pr ovide the best possible grip in
wintry road conditions.
R For M+S tyres, only use tyres with the same
tread.
R Obser vethe maximum permissible speed for
th e M+S tyres /t ted.
If th e tyre's maximum speed is below that of
th eve hicle, this must be indicated byan
appropriate label in the driver's /eld of vision.
R Run in new tyres at moderate speeds forthe
/r st 100 km.
R Replace the tyres aTer six years at the latest,
re ga rdless of wear.
R When r
When r eplacing wit
eplacing wit h tyr
h tyres t
es that do no
hat do no t f
t featur
eatur e
e
r
r un-0at
un-0at c
char
har act
acter
eris
istics:
tics: vehicles with
MOExtended tyres are not equipped with a
TIREFIT kit at thefa ctor y.Equip theve hicle
with a TIREFIT kit aTer replacing with tyres
th at do not feature run-0at characteristics,
e.g. winter tyres.
% You can permanently limit the maximum
speed for driving with winter tyres
(/ page 226). Fo
r more information on wheels and tyres, con-
ta ct a quali/ed specialist workshop.
Be sure toalso obser vethefo llowing fur ther rela-
te d subjects:
R Notes on tyre pressure (/ page 364)
R Tyre pressure table (/ page 365)
R Notes on the emer gency spa rewheel
(/ page 378) N No
ot
tes on int
es on int erc
erchanging wheels
hanging wheels &
W
WARNING
ARNING Risk of injury thro ugh di.erent
wheel sizes
Inter changing the front and rear wheels can
se verely impair the driving characteristics.
The disk brakes or wheel suspension compo-
nents may also be damaged. #
Only inter change the front and rear
wheels if the wheels and tyres ha vethe
same dimensions. Wheels and tyres
371
371

Information on coolant is
available at thefo l-
lowing locations:
R Inthe Mercedes-Benz Speci/cation for
Operating Fluids 320.1
- Athttps://be vo.mercedes-benz.com
- Inthe Mercedes-Benz BeVo App
R Ataqu ali/ed specialist workshop *
N NOOTE TE Overheating at high outside temp er-
atures If an inappropriate coolant is used,
the engine
cooling system is not su1ciently pr otected
against overheating and cor rosion at high out-
side temp eratures. #
Only use coolant appr ovedby Mercedes-
Benz. #
Obser vethe inst ructions in the
Mercedes-Benz Speci/cations for Oper-
ating Fluids 320.1. Ha
ve the coolant regula rly re placed at a quali/ed
specialist workshop. Proportion of antif
reeze concentrate in the engine
cooling system:
R A minimum of 50% (antifreeze pr otection down
to about -37°C)
R A maximum of 55% (antif reeze pr otection
down to-45°C) N
No ot
tes on windscr
es on windscr een w
een washer
asher 0uid
0uid Obser
vethe no tes on operating 0uids
(/ page 385). &
W
WARNING
ARNING ‑ Risk of /re and injury due to
windscreen washer concent rate
Wi ndsc reen washer concent rate is highly 0am-
mable. It could ignite if it comes into contact
with hot engine component parts or the
ex haust system. #
Make sure that no windscreen washer
concent rate spills out next tothe /ller
opening. *
N NOOTE
TE Damage totheex terior lighting due
to unsuitable windscreen washer 0uid Unsuitable windscreen
washer 0uids may
damage the plastic sur face of theex terior
lighting. #
Only use windscreen washer 0uids which
are also suitable for use on plastic sur fa-
ces, e.g. MB SummerFit or MB WinterFit. *
N
NOOTE
TE Bloc ked spr aynozzles caused by
mixing windscreen washer 0uids #
Do not mix MB SummerFit and MB Win-
te rFit with other windscreen washer 0u-
ids. Do not use distilled or de-ionised
water. Other-
wise, the /ll le vel sensor may be triggered er rone-
ous ly.
Re commended windscreen washer 0uid:
R abo vefreezing point: e.g. MB SummerFit
R below freezing point: e.g. MB WinterFit 394
394
Te
ch nical data

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
:
Malfunction See Owner's
Manual *T
heexterior lighting is malfunctioning. #
Consult a quali/ed specialist workshop.
*V Vehicles wit ehicles wit h a tr
h a trailer hitc
ailer hitc h:
h:a fuse may ha veblown. #
Stop theve hicle in accordance with the tra1c conditions. #
Check the fuses and replace them if necessary (/ page 360).
:
Automatic driving lights
inoperative *T
he light sensor for automatic driving lights is malfunctioning. #
Consult a quali/ed specialist workshop.
:
Active Light System inoper-
ative *T
he active headlamps are malfunctioning. #
Consult a quali/ed specialist workshop. Displ
aymessages and warning/indicator lamps
409
409

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
¸
Ã
ç
Ä
temporarily unavailable
Sensors dirty *F
ront and corner radar sensors (hereaTer "sensors") are malfunctioning. Possible causes:
R The senso rsare dirty
R Heavy rain or snow
R Extended country driving without other tra1c, e.g. in the desert
Driving systems and driving saf ety sy stems ma y be malfunctioning or temp orarily una vailable. The brake system, steer-
ing and drive system will continue tofunction normall y. #
Drive on
Once the causes of the problem are no longer present, the driving systems and driving saf ety sy stems will be available
again and the cor responding symbols will be switched o..
If th e display message does not disappear: #
Stop theve hicle in accordance with the tra1c conditions. #
Clean all sensor co vers from outside (/ page 214). #
Restart theve hicle. 448 448
Displ
aymessages and warning/indicator lamps

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
#
Stop vehicle Leave engine
running *T
he 12 V battery charge leve l is too lo w. #
Stop theve hicle immediately in accordance with the tra1c conditions. Do not continue driving. #
Leavetheve hicle running #
Ifth e display message disappears: drive on. #
Ifth e display message does not disappear: consult a quali/ed specialist workshop. T T
yr
yr e pr
e pr essur
essur e monit
e monit or
or Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/conseq uences and
uences andM
MSolutions
Solutions
Tyre press. monitor cur-
rently unavailable *T
here is inter fere nce from a po werful radio signal source. As a result, no signals from the tyre pressure sensors are
being received. The tyre pressure monitoring system is temp orarily una vailable.
The tyre pressure monitoring system will restart au tomatically as soon as the cause has been recti/ed. #
Drive on.
Tyre press. monitor inoper-
ative *T
he tyre pressure moni toring system is malfunctioning. &
W WARNI NG
ARNI NGThere is a risk of an accident if the tyre pressure monitoring system is malfunctioning
The tyre pressure monitoring system cannot issue a warning if there is pressure loss in one or more of the tyres.
Ty res with insu1cient tyre pressure may impair the driving characteristics as well as steering and braking. #
Have the tyre pressure monitoring system checked at a quali/ed specialist workshop. 458
458
Displ
aymessages and warning/indicator lamps

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
Tyre press. monitor inoper-
ative No wheel sensors *T
he wheels /tted do not ha vesuitable tyre pressure senso rs. The tyre pressure monitoring system is deactivated. #
Fit wheels with suitable tyre pressure sensors.
h
Wheel sensor(s) missing *T
here is no signal from the tyre pressure sensor of one or more wheels. No pressure value is displa yedfo rth e a.ected
tyre. #
Have thefa ulty tyre pressure sensor replaced at a quali/ed specialist workshop.
h
Check tyre(s) *T
he tyre pressure in one or more tyres has dropped signi/cantl y.
The wheel position is displa yed. A warning tone also sounds. &
W WARNI NG
ARNI NGRisk of an accident due toinsu1cient tyre pressure
R The tyres can burst.
R The tyres can wearexcessively and/or une venly.
R The driving characteristics as well as the steering and braking may be greatly impaired.
Yo u could then lose control of theve hicle. #
Obser vethere commended tyre pressures. #
Adjust the tyre pressure if necessar y. #
Stop theve hicle in accordance with the tra1c conditions. #
Check the tyre pressure (/ page 364) andthe tyres. Display messages and
warning/indicator lamps
459
459

Displa
Displa
y messag
y messag es P
es Possible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions #
Switch o. theve hicle. #
Add 1 l of engine oil (/ page 328). #
Check the engine oil le vel.
No tes on engine oil (/ page 391).
5
Engine oil pressure Stop
Switch off engine *T
he oil pressure is too lo w.
* N
N O OTE
TE Engine damage caused bydriving with insu1cient oil pressure #
Avoid driving with insu1cient oil pressure. #
Stop theve hicle immediately in accordance with the tra1c conditions. Do not continue driving. #
Switch o. theve hicle. #
Consult a quali/ed specialist workshop.
5
Engine oil level cannot be
measured *T
he elect rical connection tothe oil le vel sensor has been inter rupted or the oil le vel sensor is faulty. #
Consult a quali/ed speciali stwo rkshop. Displ
aymessages and warning/indicator lamps
467 467

W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
ï
Tr ailer tow hitch warning
lamp *T
hered trailer hitch warning lamp is lit.
The trailer hitch is not operational. &
W
WARNING
ARNING Risk of an accident if the ball neck is not loc ked
The trailer may become de tach ed. #
Stop theve hicle immediately in accordance with the tra1c conditions. Do not continue driving. #
Uncouple the trailer and secure it against rolling away. #
Initiate a new swivelling procedu reand do not re-couple the trailer until the display message disappears. #
Notethe messages on the instrument displa y.Engine
Engine
W
W
ar
ar ning/indicat
ning/indicat or lampP
or lam pP ossible causes/conseq
ossible causes/consequences and uences andM
MSolutions
Solutions
ÿ
Coolant warning lamp (red) *T
he red coolant warning lamp is lit while the engine is running.
Po ssible causes:
R The temp erature sensor is malfunctioning
R The coolant le vel is too low
R The air supply tothera diator is obstructed
R The radiator fan is faulty Display message
s andwarning/indicator lamps
473
473