2021 MERCEDES-BENZ A-CLASS SALOON Owners Manual

R
R
es
estr traint syst
aint syst em
em Pr
ot
Pr otection pro
ection pro vided b
vided by t
y the r
he r es
estr traint syst
aint syst em
em The
restraint system includes thefo llowing com-
ponents:
R Seat belt system
R Airbags
R Child restraint system
R Child seat secu ring systems
The restraint system can help pr eventtheve hicle
occupants from coming into contact with parts of
th eve hicle interior in theev ent of an accident. In
th eev ent of an accident, there straint system can
also reduce thefo rc es towhich theve hicle occu-
pants are subjected.
A seat belt can only pr ovide the best le vel of pro-
te ction if it is worncor rectl y.Depending on the
de tected accident situation, seat belt tensioners
and/or airbags supplement the pr otection o.ered
by a cor rectly wornseat belt. Seat belt tensioners
and/or airbags are not deplo yed in every acci-
dent. In order
forth ere straint system toprov ide the
intended le vel of pr otection, each vehicle occu-
pant must obser vethefo llowing information:
R Fasten seat belts co rrectl y.
R Sit in an almost up right seat position with their
back against the seat backrest.
R Sit with their feet resting on the 0oor, if possi-
ble.
R Always secure persons under 1.50 m tall in an
additional restraint system suitable for
Mercedes-Benz vehicles.
Ho wever,no system available today can com-
ple tely eliminate injuries and fatalities in every
accident situation. In particular, the seat belt and
airbag generally do not pr otect against objects
penetrating theve hicle from the outside. It is also
not possible tocomple tely rule out therisk of
injury caused bythe airbag deploying. Limit Limit
ations of t
ations of t he prot
he pr otection pro
ection pro vided b
vided by t
y the
he
r
r es
estr traint syst
aint syst em
em &
W
WARNING
ARNING Risk of injury or death due to
modi/cations tothere straint system
Ve hicle occupants may no lon ger be pr otected
as intended if alterations are made tothe
re straint system. #
Never alter the parts of there straint sys-
te m. #
Neverta mp er with the wiring or any elec-
tronic component parts or their soT-
wa re. If it is necessary
tomodify theve hicle toaccom-
modate a person with disabilities, contact a quali-
/ed specialist workshop.
Mercedes-Benz recommends that you use driving
aids which ha vebeen appr ovedfo ryo ur vehicle by
Mercedes-Benz. 46
46
Occupant sa
fety

R
R
es
estr traint syst
aint syst em functionality
em functionality When
theve hicle is switched on, a self-test is per-
fo rm ed, during which the6 restraint system
wa rning lamp lights up. It goes out no later than a
few seconds aTer theve hicle is star ted. The com-
ponents of there straint system are then func-
tional. Malfunctioning r
Malfunctioning r
es
estr traint syst
aint syst em
em A malfunction has occur
red in there straint sys-
te m if:
R the6 restraint system warning lamp does
not light up when theve hicle is switched on
R the6 restraint system warning lamp lights
up continuously or repeatedly during a journey
All v
All v ehicles, ex
ehicles, excep
cep t plug-in h
t plug-in h ybr
ybrid:
id: &
W
WARNING
ARNING Risk of injury due tomalfunc-
tions in there straint system
Co mp onents in there straint system ma y be
acti vated unintentionally or not deploy as
intended in an accident. #
Have there straint system checked and
re paired immediately at a quali/ed spe-
cialist workshop. Plug-in h
Plug-in h
ybr
ybrid:
id: &
D
DAN
AN GER
GER Risk of fatal injuries due to
re straint system malfunctions
Co mp onents in there straint system ma y be
acti vated unintentionally or not deploy as plan-
ned in an accident. In theeve nt of an acci-
dent, the high-voltage on-board electrical sys-
te m may not be deactivated as intended.
Yo u may su.er an electric shock if youto uch
th e damaged components of the high-voltage
on-board electrical system. #
Have there straint system checked and
re paired immediately at a quali/ed spe-
cialist workshop. #
ATer an accident, switch o. theve hicle
immediatel y. F
F
unction of t
unction of t he r
he res
estrtraint syst
aint syst em in an accident
em in an accident How
there straint system works is de term ined by
th e se verity of the impact de tected and the type
of accident anticipated:
R Frontal impact
R Rear impact
R Side impact
R Only for cer tain countries: rollo ver
The activation thre sholds forth e components of
th ere straint system are de term ined based on the
ev aluation of the sensor values measured at vari-
ous points in theve hicle. This process is pre-e mp-
tive in nature. The triggering/deployment of the
components of there straint system must take
place in good time at the start of the collision.
Fa ctors which can only be seen and measured
aTer a collision has occur red do not play a deci-
sive role in the deployment of an airbag. Nor do
th ey prov ide an indication of airbag deployment.
The vehicle may be deformed signi/cantly without
an airbag being deplo yed. This is the case if only
parts which are relatively easily deformed are
a.ec tedand thera te of vehicle deceleration is Occupant saf
ety
47
47

not high. Con
versely, an airbag may be depl oyed
ev en though theve hicle su.ers only minor defor-
mation. If very rigid vehicle parts such as longitu-
dinal membe rsare hit, this may result in su1-
ciently high le vels of vehicle deceleration.
Depending on the de tected deployment situation,
th e components of there straint system can be
acti vated or deplo yed independently of each
ot her:
R Seat belt tensioner: frontal impact, rear
impact, side impact, rollo ver 1
R Driver's airbag, front passenger airbag: frontal
impact
R Knee airbag: frontal impact
R Side airbag: side impact
R Window airbag: side impact, rollo ver 1
, frontal
impact
1) Only for cer tain countries.
The front passenger airbag can only be deplo yed
in an accident if thePA SSENGER AIR BAG OFF
indicator la mpis o.. If the front passenger seat is
occupied, make sure, bo thbefore and during thejourne
y,that the status of the front passenger air-
bag is cor rect (/ page 57). &
W
WARNING
ARNING Risk of burns from hot airbag
components
The airbag parts are hot aTer an airbag has
been deplo yed. #
Do not touch the airbag parts. #
Have a depl oyed airbag replaced at a
qu ali/ed specialist workshop as soon as
possible. Mercedes-Benz
recommends that you ha vethe
ve hicle towe dto aqu ali/ed specialist workshop
aTer an accident. Take this into account, particu-
lar lyif a seat belt tensioner is triggered or an air-
bag deplo yed.
If th e seat belt tensioners are triggered or an air-
bag is deplo yed, you will hear a bang, and a small
amount of powder may also be released:
R The bang will not generally a.ect your hearing.
R Ingeneral, the powder released is not hazard-
ous tohealth but may cause short- term breathing di1culties
topersons su.ering from
asthma or other pulmonary conditions.
Pr ov ided it is safe todo so, lea vetheve hicle
immediately or open the window in order to
pr ev ent breathing di1culties. Seat belts
Seat belts
Pr
ot
Pr otection pro
ection pro vided b
vided by t
y the seat belt
he seat belt Alw
aysfa sten your seat belt cor rectly before
starting a journe y.A seat belt can only pr ovide
th e best le vel of pr otection if it is worncor rectl y. &
W
WARNI NG
ARNI NGRisk of injury or dea thdue to
incor rectly fastened seat belt
If th e seat belt is not worncor rectl y,it cannot
per form its intended pr otective function.
In addition, an incor rectly fastened seat belt
can also cause injuries, forex ample, in the
ev ent of an accident or when braking or
ch anging direction suddenl y.48
48
Occupant saf
ety

#
Always ensu rethat all vehicle occupants
ha ve their seat belts fastened co rrectly
and are sitting proper ly.Alw
ays obser vethe inst ructions about the cor rect
driver's seat position and adjusting the seat
(/ page 104).
In order forth e cor rectly wornseat belt toprov ide
th e intended le vel of pr otection, each vehicle
occupant must obser vethefo llowing information:
R The seat belt must not be twisted and must /t
tightly and snugly across the body.
R The seat belt must be routed across the
cent reofthe shoulder and as low down across
th e hips as possible.
R The shoulder section of the seat belt should
not touch your neck nor be routed under your
arm or behind your bac k.
R Avoid wearing bulky clo thing, e.g. a winter
coat.
R Push the lap belt down as far as possible
across your hips and pull tight with the shoul-
der section of the belt. Neverro ute the lap
belt across your abdomen. Pregnant
women must also take particular
care with this.
R Neverro ute the seat belt across sharp, poin-
te d, abrasive or fragile objects.
R Only one person should use each seat belt at
any one time.
R Never secure objects with a seat belt if the
seat belt is also being used byone of theve hi-
cle's occupants.
Also ensu rethat no objects, e.g. a cushion,
are ever placed between a person and the
seat.
If ch ildren are tr avelling in theve hicle, be sure to
obser vethe inst ructions and saf ety no tes on
"Child ren in theve hicle" (/ page 62).
Alw ays obser vethe inst ructions for loading the
ve hicle when securing objects, lug gage or loads
(/ page 118). Limit Limit
ations of t
ations of t he prot
he pr otection pro
ection pro vided b
vided by t
y the seat
he seat
belt
belt &
W
WARNING
ARNING Risk of injury or death due to
incor rect seat position
The seat belt will not o.er the intended le vel
of pr otection if you ha venot mo vedth e seat
backrest toan almost vertical position.
In particular, you may slip under the seatbelt
and injure yourself. #
Adjust the seat proper lybefore begin-
ning your journe y. #
Always ensu rethat the seat backrest is
in an almost vertical position and that
th e shoulder section of your seat belt is
ro uted across the centre of your shoul-
der. Occupant saf
ety
49
49

&
W
WARNI NG
ARNI NGRisk of injury or dea thwhen
additional restraint systems are not used
fo r persons with a smaller stature
Pe rsons under 1.50 m tall cannot wearthe
seat belt cor rectly without a suitable addi-
tional restraint system. #
Always secure persons under 1.50 m tall
in a suitable restraint system. &
W
WARNING
ARNING Risk of injur y or death due to
damaged or modi/ed seat belts
Seat belts cannot pr ovide pr otection in thefo l-
lowing situations:
R the seat belt is damaged, has been modi-
/ed, is extremely dirty, blea ched or dyed
R the seat belt buckle is damaged or
ex tremely dirty
R modi/cations ha vebeen made tothe seat
belt tensioner, seat belt anchorage or seat
belt retractor
Seat belts may sustain non-visible damage in
an accident, e.g. due toglass splinters. Modi/ed or damaged seat belts could
tear or
fa il in theev ent of an accident, forex ample.
Modi/ed seat belt tensioners could acciden-
ta lly trigger or failto function as intended. #
Never modify the seat belt system, for
ex ample the seat belt, seat belt buckle,
seat belt tensioner, seat belt anchorage
and seat belt retractor. #
Make sure that the seat belts are undam-
aged, not wornand clean. #
Always ha vethe seat belts checked
immediately aTer an accident at a quali-
/ed specialist workshop. Mercedes-Benz
recommends that you use seat
belts which ha vebeen appr ovedfo ryo ur vehicle
by Mercedes-Benz. &
W
WARNI NG
ARNI NGRisk of injury or dea thfrom
deplo yedpy rotech nic seat belt tensioners
Pyro tech nic seat belt tensioners that ha ve
been deplo yed are no longer operational and
are unable toper form their intended pr otec-
tive function. #
Therefore, ha vedeplo yedpy rotech nic
seat belt tensioners immedia tely
re placed at a quali/ed specialist work-
shop. Mercedes-Benz
recommends that you ha vethe
ve hicle towe dto aqu ali/ed specialist workshop
aTer an accident.
* N
NOOTE
TE Damage caused bytrapping the
seat belt If an unused seat belt is not fully
retracted, it
may become trapped in the door or in the seat
mechanism. #
Always ensu rethat an unused seat belt
is fully retracted. F
F
ast
ast ening seat belts
ening seat belts If
th e seat belt is pulled quickly or sharpl y,the
seat belt retractor loc ks. The seat belt strap can-
not be pulled out any fur ther. 50
50
Occupant saf
ety

#
Always engage seat belt tongue 2ofthe seat
belt into seat belt buckle 1ofthe cor re-
sponding seat.
% A seat belt can only pr ovide the best le vel of
pr otection if it is worncor rectl y.Obser vethe
no tes on fastening the seat belt (/ page 48).*
N
NOOTE
TE Deployment of components of the
re straint system when the front passenger
seat is unoccupied and a seat belt is
buckled When
the front passenger seat is unoccupied
and the seat belt tongue of the seat belt is
engaged in the seat belt buckle, components
of there straint system ma y deployunnecessa-
ri ly on the front passenger side, e.g. the seat
belt tensioner. #
Only buckle the seat belts as intended. %
Obser vethe no tes on st owage areas
(/ page 118).
Information on /tting a child restraint system
and on children tr avelling in theve hicle can
be found in the "Children in theve hicle" sec-
tion (/ page 66). Seat belt adjus Seat belt adjustment function
tment function V
V
ehicles wit
ehicles wit h PRE-S
h PRE-SAFE
AFE®
®
:
:aTer a front seat belt
has been fastened, the automatic seat belt adjust- ment may apply a cer
tain tightening forc e. Do not
hold the seat belt tightly while it is adjusting.
Yo u can activate and deactivate the seat belt
adjustment function using the multimedia system
(/ page 51). A
A
ctiv
ctiv ating/deactiv
ating/deactiv ating seat belt adjus
ating seat belt adjustment via tment via
t
t he multimedia syst
he multimedia syst em
em Multimedia system:
4 © 5
Settings 5
Vehicle #
Activate or deactivate Belt adjustment. R
R
eleasing seat belts
eleasing seat belts #
Press there lease button in the seat belt
buckle and guide the seat belt back with the
seat belt tongue. Seat belt w
Seat belt w
ar
arning function f
ning function f or t
or the dr
he dr iv
iver and fr
er and fr ont
ont
passeng
passeng er
er The
ü seat belt warning lamp in the Instru-
ment Display is a reminder that all vehicle occu-
pants must weartheir seat belts cor rectl y. Occupant saf
ety
51
51

In addition, a
warning tone may sound.
As soon as the driver and front passenger fasten
th eir seat belts, the seat belt warning goes out. F
F
unction of t
unction of t he r
he rear seat belt st
ear seat belt st atus display
atus displayThe
rear seat belt status displ ayis only available
fo r cer tain countries. When
theve hicle is switched on, there ar seat
belt status displ ayinforms youfo r a cer tain
amount of time which rear seat belt is not fas-
te ned. Yo
u can immediately dismiss there ar seat belt
status displ ayusing the back button on the leT-
hand side of the steering wheel (/ page 273).
If a vehicle occupant unfastens a seat belt in the
re ar while theve hicle is motion, there ar seat belt
status displ ayappears again.
In addition, a warning tone may sound. In this
case, there ar seat belt status displ aycannot be
hidden using the back button on the leT-hand side
of the steering wheel. Airbags
Airbags
Ov
Ov
er
ervie
vie w of airbags
w of airbags 1
Knee airbag
2 Driver's airbag
3 Front passenger airbag
4 Window airbag
5 Side airbag
The installation location of an airbag is identi/ed
by the AIRB AGsymbol.
When enabled, an airbag can pr ovide additional
pr otection forth ere specti ve vehicle occupant. 52
52
Occupant saf
ety

Po
tential pr otection pr ovided byeach airbag:
R Knee airbag: thigh, knee and lo wer leg
R Driver's airbag, front passenger airbag: head
and ribcage
R Window airbag: head
R Side airbag: ribcage and pelvis
* N
NO OTE
TE Mercedes-AMG vehicles #
Obser vethe no tes in the Supplement.
Yo u could otherwise failto recognise
dangers. &
W
W ARNING
ARNING Risk of injury or death if the co-
driver airbag is enabled
If th e co-driver airbag is enabled, a child on
th e co-driver seat may be struck bythe co-
driver airbag during an accident.
NEVER use a rear wa rd-facing child restraint
system on a seat wi than ENABLED FRONT
AIR BAG; DEATH or SERIOUS INJURY tothe
CHILD ca n occur. When /tting a
child restraint system tothe front
passenger seat, obser vetheve hicle-speci/c infor-
mation (/ page 77). Also, alw ays obser vethe
no tes on rear wa rd-facing or forw ard-facing child
re straint systems on the front passenger seat
(/ page 76).
Inf Inf or
ormation on aut
mation on aut omatic fr
omatic front passeng
ont passeng er airbag
er airbag
shut
shut o.
o.
The front passenger airbag can only be deplo yed
in an accident if thePA SSENGER AIR BAG OFF
indicator la mpis o.. If the front passenger seat is
occupied, make sure, bo thbefore and during the
journe y,that the status of the front passenger air-
bag is cor rect (/ page 57).
* NO
NO TE
TEDeployment of components of the
re straint system when the front passenger
seat is unoccupied In an accident,
the components of the
re straint system ma y deployunnecessarily on
th e front passenger side if:
R There are heavy objects on the front
passenger seat. R
The seat belt tongue is engaged in the seat
belt buckle of the front passenger seat and
th e front passenger seat is unoccupied. #
Stow objects in a suitable place. #
Only one person should use each seat
belt at any one time. Depending on
the de tected accident situation, the
wind owairbag on the front passenger side may
deplo y.The airbag is deplo yedre ga rdless of
whe ther the front passenger seat is occupied. Pr
ot
Pr otection pro
ection pro vided b
vided by t
y the airbags
he airbags Depending on
the accident situation, an airbag
may supplement the pr otection o.ered bya cor-
re ctly fastened seat belt. &
W
WARNING
ARNING Risk of injur y or death due to
an inco rrect seat position
If yo u deviate from the cor rect seat position,
th e airbag cannot per form its intended pr otec-
tive function. Occupant saf
ety
53
53