belt MERCEDES-BENZ B-CLASS HATCHBACK 2021 Service Manual

Electr
Electr
ic par
ic parking br
king br ake
ake F
F
unction of t
unction of t he electr
he electric par
ic par king br
king br ak
ak e (appl
e (appl ying
ying
aut
aut omaticall
omaticall y)
y) &
W
WARNING
ARNING Risk of accident and injury due
to leaving children unattended in theve hi-
cle
If ch ildren are leT unattended in theve hicle,
th ey could, in particular:
R open doors, thereby endangering other
persons or road users.
R get out and be struck byoncoming tra1c.
R operate vehicle equipment and become
trapped, forex ample.
In addition, thech ildren could also set the
ve hicle in motion by,fo rex ample:
R releasing the parking brake.
R changing the transmission position.
R starting theve hicle. #
Never lea vechildren unattended in the
ve hicle. #
When leaving theve hicle, alw aysta ke the
ke y with you and lock theve hicle. #
Keep theve hicle key out of there ach of
ch ildren. V
V
ehicles wit
ehicles wit h manual tr
h manual tr ansmission:
ansmission:
The electr
The electr ic par
ic parking br
king br ak
ake is applied if t
e is applied if t he v
he vehicle
ehicle
is br
is br ought t
ought t o a st
o a stands
andstill and one of ttill and one of t he f
he follo
ollowing
wing
conditions is
conditions is ful/lled:
ful/lled:
R The vehicle has pr eviously been driven at
speeds greater than 3 km/h.
R The vehicle is switched o..
R The driver's door is opened.
% Toprev ent application: pull the handle of the
electric parking brake (/ page 221).
In t
In t he f
he f ollo
ollowing situations, t
wing situations, t he electr
he electric par
ic parking
king
br
br ak
ak e is also applied:
e is also applied:
R The HOLD function is keeping theve hicle sta-
tionar y.
R In addition, one of t
In addition, one of t he f
he follo
ollo wing conditions
wing conditions
mus
mus t be
t be ful/lled:
ful/lled:
- The vehicle is switched o.. -
The seat belt tongue is not inse rted in the
seat belt buckle of the driver's seat and
th e driver's door is opened.
- There is a system malfunction.
- The po wer supply is insu1cient.
- The vehicle is stationary for a lengt hy
period.
When the electric parking brake is applied, the
re d0024 indicator lamp lights up in the inst ru-
ment cluster.
If th e electric parking brake is not applied when
th e driver's door is opened, theRisk of vehicle
rolling away Apply parking brake See Owner's
Manual message appears.
% The electric parking brake is not automatically
applied if theve hicle is switched o. bythe
ECO start/s top function.
V
V ehicles wit ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission:
The electr
The electr ic par
ic parking br
king br ak
ake is applied if t
e is applied if t he tr
he tr ans-
ans-
mission is in position
mission is in position 005D
005Dand one of t
and one of t he f
he follo
ollowing
wing
conditions is
conditions is ful/lled:
ful/lled:
R The vehicle is switched o.. Driving and parking
219
219

R
The seat belt tongue is not inse rted in the seat
belt buckle of the driver's seat and the driver's
door is opened.
% Toprev ent application: pull the handle of the
electric parking brake (/ page 221).
In t
In t he f
he f ollo
ollowing situations, t
wing situations, t he electr
he electric par
ic parking
king
br
br ak
ak e is also applied:
e is also applied:
R The HOLD function is keeping theve hicle sta-
tionar y.
R Active Parking Assist is keeping theve hicle
stationar y.
R Active Distance Assist DISTRONIC is bringing
th eve hicle toa standstill.
R In addition, one of t
In addition, one of t he f
he follo
ollowing conditions
wing conditions
mus
mus t be
t be ful/lled:
ful/lled:
- The vehicle is switched o..
- The seat belt tongue is not inse rted in the
seat belt buckle of the driver's seat and
th e driver's door is opened.
- There is a system malfunction.
- The po wer supply is insu1cient. -
The vehicle is stationary for a lengt hy
period.
When the electric parking brake is applied, the
re d0024 indicator lamp lights up in the inst ru-
ment clus ter.
% The electric parking brake is not automatically
applied if theve hicle is switched o. bythe
ECO start/s top function.
F F unction of t unction of t he electr
he electric par
ic parking br
king br ak
ake (r
e (r eleasing
eleasing
aut
aut omaticall
omaticall y)
y)
The electr
The electr ic par
ic parking br
king br ak
ake is r
e is r eleased when t
eleased when t he
he
f
f ollo
ollo wing conditions ar
wing conditions ar e
eful/lled:
ful/lled:
R The driver's door is closed.
R The vehicle has been star ted.
R V
Vehicles wit
ehicles wit h manual tr
h manual tr ansmission:
ansmission: age ar has
been selected, youre lease the clutch pedal
and depress the accelerator pedal.
R You apply the brakes and shiT from neutral 005C
into reve rsege ar 005E or a forw ard gear ( 0047 -
004C) when on le velgr ound.
R V
Vehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: the
transmission is in position 005Bor005E and you depress
the accelerator pedal or you shiT
from transmission position 005Dto005B or005E
when on le velgr ound.
R Ifth e transmission is in position 005E,theta il-
ga te must be closed.
R The seat belt tongue is inse rted into the seat
belt buckle of the driver's seat.
If th e seat belt tongue is not inse rted into the
seat belt buckle of the driver's seat, one of the
fo llowing conditions must be ful/lled:
- You shiT from transmission position 005D.
or
- You ha veprev iously driven at speeds
gr eater than 3 km/h.
When the electric parking brake is released, the
re d0024 indicator lamp in the inst rument clus ter
goes out. 220
220
Driving and parking

Syst
Syst
em limits
em limits
ST EER CONTROL may be impaired or may not
function in thefo llowing situations:
R ESP ®
is deactivated.
R ESP ®
is malfunctioning.
R The steering is malfunctioning.
If ESP ®
is malfunctioning, you will be assisted fur-
th er by the electric po wer steering. HOLD function
HOLD function
HOLD function
HOLD function
The HOLD function holds
theve hicle at a stand-
still without requ iring youto depress the brake
pedal, e.g. while waiting in tra1c.
The HOLD function is only an aid. The responsibil-
ity forth eve hicle safely standing still remains with
th e driver.
Syst Syst em limits em limits
The HOLD function is only intended toprov ide
assistance when driving and is not a su1cient
means of safeguarding theve hicle against rolling
awa y when stationa ry. R
The incline must not be greater than 30%.
A
A ctiv ctiv ating/deactiv
ating/deactiv ating t
ating t he HOLD function
he HOLD function &
W
WARNING
ARNING Risk of an accident due tothe
HOLD function being active when you
lea vetheve hicle
If th eve hicle is only braked with the HOLD
function it could, in thefo llowing situations,
ro llawa y:
R Ifth ere is a malfunction in the system or in
th e po wer suppl y.
R Ifth e HOLD function is deactivated by
depressing the accelerator pedal or brake
pedal, e.g. byave hicle occupant. #
Always secure theve hicle against rolling
awa y before you lea veit. R
R
eq
eq uir
uir ements:
ements:
R The vehicle is stationar y.
R The driver's door is closed or the seat belt on
th e driver's side is fastened. R
The vehicle has been star ted or has been
automatically switched o. bythe ECO start/
stop function.
R The vehicle has been star ted.
R The electric parking brake is released.
R Active Distance Assist DISTRONIC is deactiva-
te d.
R V
V ehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: the
transmission is in position 005B,005Eor005C.
A
A ctiv
ctiv ating t
ating t he HOLD function
he HOLD function #
Depress the brake pedal, and aTer a short
time quickly depress fur ther until the00D9
display appears in the Instrument Displa y. #
Release the brake pedal.
Deactiv
Deactiv ating t
ating the HOLD function
he HOLD function #
Depress the accelerator pedal topull away.
or #
Depress the brake pedal until the00D9 display
disappears from the Instrument Displa y.228
228
Driving and parking

The HOLD function is deactivated in
thefo llowing
situations:
R Active Distance Assist DISTRONIC is acti va-
te d.
R V
Vehicles wit
ehicles wit h aut
h aut omatic tr
omatic tr ansmission:
ansmission: the
transmission is shiTed toposition 005D.
R The vehicle is secured with the electric par k-
ing brake.
In thefo llowing situations, theve hicle is held by
transmission position 005Dand/or bythe electric
parking brake:
R The seat belt is unfastened and the driver's
door is opened.
R The vehicle is switched o..
R There is a system malfunction.
R The po wer supply is insu1cient.
V
V ehicles wit
ehicles wit h manual tr
h manual tr ansmission
ansmission
The Brake immediately message may also appear
in the Instrument Displa y:#
Immediately depress the brake pedal /rmly
until thewa rning message disappears.
The HOLD function is deactivated. A horn sounds at
regular inter vals if, despite the
Brake immediately message,you switch o. the
ve hicle, remo veyour seat belt and open the driv-
er's door. If you attem pttolock theve hicle, the
horn tone becomes louder. The vehicle cann otbe
loc ked until you ha vedeactivated the HOLD func-
tion.
% Once you ha veswitched o. theve hicle, you
cannot restart it until you ha vedeactivated
th e HOLD function. F
F
unction of Hill St
unction of Hill Star
art Assist
t Assist Hill
Start Assist holds theve hicle for a short time
when pulling away on a hill under thefo llowing
conditions:
R V
V ehicles wit
ehicles wit h aut
h automatic tr
omatic tr ansmission:
ansmission: the
transmission is in position 005Bor005E.
R The electric parking brake is released.
This gives you enough time tomo veyour foot
from the brake pedal tothe accelerator pedal and
depress it before theve hicle begins torollaw ay. &
W
WARNI NG
ARNI NGRisk of accident and injury due
to theve hicle rolling away
ATer a sho rttime, Hill Start Assist no lon ger
holds theve hicle. #
SwiTly mo veyour foot from the brake
pedal tothe accelerator pedal. Do not
lea vetheve hicle when it is being held by
Hill Start Assist. F
F
unction of A
unction of A dap
daptiv
tive Br
e Br ak
ake Lights
e Lights Ad
aptive Brake Lights warnfollowing tra1c in an
emer gency braking situation with thefo llowing
actions:
R By 0ashing the brake lamps
R By activating the hazard warning lights
If th eve hicle is braked sharply from speeds abo ve
50 km/h, the brake lamps 0ash rapidl y.This pro-
vides tra1c tr avelling behind you with an even
more noticeable warning.
If th eve hicle is tr avelling at speeds of more than
70 km/h at the beginning of the brake applica-
tion, the hazard warning lights switch on once the Driving and parking
229
229

If dr
owsiness or increasing lapses in concent ra-
tion are de tected, theATTENTION ASSIST: Take
a break! warning appears in the Instrument Dis-
pla y.Yo u can ackno wledge the message and take
a break where necessar y.Ifyo u do not take a
break and ATTENTION ASSIST continues todetect
increasing lapses in concentration, you will be
wa rned again aTer a minimum of 15 minutes. Yo
u can ha vethefo llowing status information for
AT TENTION ASSIST displa yed in the assistance
menu of the on-board computer:
R The length of the journey since the last break.
R The attention le vel de term ined byATTENTION
ASSIS T: -
the fuller the circle, the higher the atten-
tion le vel de term ined
- asyour attention wanes, the circle in the
cent reofthe display becomes smaller
If AT TENTION ASSIST is unable tocalculate the
attention le vel and cannot issue a warning, the
System suspended message appears.
If a warning is given in the Instrument Displa y,the
multimedia system o.ers tosear chfor a rest
area. You can select a rest area and start naviga-
tion tothis rest area. This function can be acti va-
te d and deactivated in the multimedia system.
If AT TENTION ASSIST is deactivated, theÛ
symbol appears in the assistance graphic in the
Instrument Displ ay. ATer theve hicle is star ted,
AT TENTION ASSIST is automatically activated. The
last selected sensitivity le velre mains stored.
Syst
Syst em limits
em limits
AT TENTION ASSIST is active in the 60 km/h to
200 km/h speed range. Pa
rticular lyin thefo llowing situations, ATTENTION
ASSIST only functions in a restric ted manner and
wa rnings may be dela yed or not occur:
R Ifyo u ha vebeen driving for less than appr ox-
imately 30 minutes.
R Ifth ero ad condition is poor (une venro ad sur-
fa ce or po tholes).
R Ifth ere is a strong side wind.
R Ifyo u adopt a sporty driving style (high corner-
ing speeds or high rates of acceleration).
R IfAc tive Steering Assist is activated and active
(/ page 241).
R Ifth e time has been set incor rectl y.
R Ifyo uch ange lanes and vary your speed fre-
qu ently in active driving situations.
The ATTENTION ASSIST dr owsiness or alertness
assessment is reset and restar ted when continu-
ing the journey in thefo llowing situations:
R You switch o. theve hicle.
R Ifyo u unfasten your seat belt and open the
driver's door (e.g. tochange drivers or take a
break). Driving and parking
231
231

to
ne sounds in addition tothe visual warning mes-
sage.
If th e driver still does not respond tothewa rning,
th eBeginning emergency stop message appears
in the Instrument Displa y.Ifth e driver still does
not respond, Active Distance Assist DISTRONIC
re duces the speed. The vehicle is decelerated in
stages toa standstill.
Depending on the countr y,at speeds below
60 km/h the hazard warning lights switch on
automaticall y.
When theve hicle is stationar y,thefo llowing
actions are car ried out:
R The vehicle is secured with the electric par k-
ing brake.
R Active Distance Assist DISTRONIC is ended.
R The vehicle is unloc ked.
R If possible, an emer gency call is placed tothe
Mercedes-Benz eme rgency call centre.
The driver can cancel the deceleration at any time
by per form ing one of thefo llowing actions:
R Steering R
Braking or accelerating
R Deactivating Active Distance Assist
DISTRONIC A A
ctiv
ctiv e Br
e Br ak
ake Assist
e Assist F
F
unction of A
unction of A ctiv
ctive Br
e Br ak
ake Assist
e Assist
Ac tive Brake Assist consists of thefo llowing func-
tions:
R Distance warning function
R Autonomous braking function
R Situation-dependent braking assistance
R V
Vehicles wit
ehicles wit h Dr
h Driving Assist
iving Assist ance P
ance Pack
ackag
age:
e: Eva-
sive Steering Assist and cornering function
Ac tive Brake Assist can help youto minimise the
ri sk of a collision with vehicles, cyclists or pedes-
trians or toreduce the e.ects of such a collision.
If Ac tive Brake Assist has de tected a risk of colli-
sion, a warning tone sounds and theL dis-
ta nce warning lamp lights up in the inst rument
cluster. V V
ehicles wit ehicles wit h PRE-S
h PRE-SAFE
AFE®
®
:
:depending on the coun-
tr y, an additional haptic warning occurs in the
fo rm of slight, repeated tensioning of the seat
belt.
If yo u do not react tothewa rning, autonomous
braking can be initiated in critical situations.
In especially critical situations, Active Brake Assist
can initiate autonomous braking directl y.In this
case, thewa rning lamp and warning tone occur
simultaneously with the braking application.
If yo u apply the brake yourself in a critical situa-
tion or apply the brake during autonomous brak-
ing, situation-dependent braking assistance
occurs. The brake pressure increases up tomaxi-
mum full-s top braking if necessar y.
Obser vethe no tes on driving systems and your
re sponsibility; you may otherwise failto recognise
dangers (/ page 223). 244 244
Driving and parking

If autonomous braking or situation-dependent
braking assis
tance has occur red, display 1
appears in the Instrument Display and then auto-
matically goes out aTer a short time.
If th e autonomous braking function or the situa-
tion-dependent braking assistance is triggered,
additional pr eventive measures for occupant pro-
te ction (PRE- SAFE®
) may also be initiated. &
W WARNING ARNING Risk of an accident caused by
limited de tection per form ance of Active
Brake Assist
Ac tive Brake Assist cannot alw ays clear lyiden-
tify objects and complex tra1c situations. In such cases,
Active Brake Assist might:
R Give a warning or brake without reason
R Not give a warning or not brake
Ac tive Brake Assist is only an aid. The driver is
re sponsible for maintaining a su1ciently safe
distance totheve hicle in front, vehicle speed
and for braking in good time. #
Always pay careful attention tothe tra1c
situation; do not relyonActive Brake
Assist alone. #
Be prepa redto brake or swer veif neces-
sar y. Also obser
vethe system limits of Active Brake
Assist.
The individual subfunctions ar
The individual subfunctions ar eav
e av ailable in v ailable in v ar
ari-
i-
ous speed r
ous speed r ang
anges:
es:
The dis tance warning function can issue a warn-
ing in thefo llowing situations:
R From appr oximately 30 km/h, if over se veral
seconds the distance maintained totheve hi-
cle tr avelling in front is insu1cient forthe driven speed,
theL distance warning lamp
lights up in the inst rument clus ter.
R From appr oximately 7 km/h, if your vehicle is
critically close toave hicle, cyclist or pedes-
trian, you will hear an intermittent warning
to ne and theL distance warning lamp
lights up in the inst rument clus ter.
V
V ehicles wit
ehicles wit h PRE-S
h PRE-SAFE
AFE®
®
:
:depending on the
count ry, an additional haptic warning occurs
in thefo rm of slight, repeated tensioning of
th e seat belt.
Brake immediately or take evasive action, pr ovi-
ded it is safe todo so and the tra1c situation
allo ws th is.
Dist
Dist ance w
ance w ar
arning function (v
ning function (v ehicles wit
ehicles without Dr
hout Driv-
iv-
ing Assist
ing Assist ance P
ance Pack
ackag
age)
e)
The distance warning function can aid you in the
fo llowing situations with an intermittent warning
to ne and a warning lamp:
R at speeds up toappr oximately 250 km/h
when approaching vehicles ahead Driving and parking
245
245

#
End the support byactively steering in
non-critical situations. #
Drive at an appropriate speed if there
are pedestrians close tothe path of your
ve hicle. Syst
Syst
em limits
em limits
Fu ll system per form ance is not yetav ailable for a
few seconds aTer switching on theve hicle or aTer
driving o..
If Ac tive Brake Assist is impaired or inoperative
due toa malfunction, the00C7 warning lamp
appears in the Instrument Displa y.
The system may be impai red or may not function,
particular lyin thefo llowing situations:
R In sno w,rain, fog, heavy spr ay, if there is glare,
in direct sunlight or in greatly varying light
conditions.
R Ifth e sensors are dirty, misted up, damaged or
co vered.
R Ifth e sensors are impaired due tointer fere nce
from other radar sources, e.g. strong radar
re 0ections in multi-s tore y car par ks. R
If a loss of tyre pressure or a defecti vetyre
has been de tected and displa yed.
R In complex tra1c situations where objects
cannot alw ays be clear lyidenti/ed.
R If pedestrians or vehicles mo vequickly in to
th e sensor de tection range.
R If pedestrians are hidden by other objects.
R Ifth e typical outline of a pedestrian cannot be
distinguished from the backg round.
R If a pedestrian is not de tected as such, e.g.
due tospecial clo thing or other objects.
R Ifth e driver's seat belt is not fastened.
R On bends wi tha tight radius.
% The Active Brake Assist sensors adjust auto-
matical lywhile a cer tain distance is being
driven aTer theve hicle has been deli vered.
Ac tive Brake Assist is una vailable or only par-
tially available during thete ach-in process.
A
A ctiv ctiv ating/deactiv
ating/deactiv ating A
ating Activ
ctive Br
e Br ak
ake Assist
e Assist
R
R eq
eq uir
uir ements:
ements:
R The vehicle is switched on. Multimedia system:
4 © 5
Settings 5
Assistance
5 Active Brake Assist #
Select the desired setting.
The setting is retained when the drive system
is next star ted.
Deactiv
Deactiv ating A
ating Activ
ctiv e Br
e Br ak
ak e Assist
e Assist
% It is recommended that you alw ays lea ve
Ac tive Brake Assist acti vated. #
Select Off.
The distance warning function, the autono-
mous braking function and Evasive Steering
Assist are deactivated.
When theve hicle is next star ted, the middle
setting is automatically selected.
% IfAc tive Brake Assist is deactivated, the00D4
symbol appears in the status bar of the Instru-
ment Displa y. 248 248
Driving and parking

The MBUX Int
The MBUX Int
er
erior Assist
ior Assist ant suppor
ant suppor ts t
ts the f
he f ollo
ollowing int
wing int er
eractions:
actions: Int
Int
er
eraction ar
action ar ea
ea Int
Inter
eraction
action Descr
Descrip
iption
tion
In front of the media display or
abo vetheto uchpad Pr
ox imity tothe control element The Interior Assistant recognises the approach of the hand towa rds a cont rol
element.
Depending on the active application, the display will be adjusted in the media
displa y.Some functions di.e rentiate between driver and front passenger.
No speci/c hand position is requ ired.
Ab ove the centre console De/ned pose Afavo urite is called up with a de/ned pose.
Below the inside rearview mir rorB rief up and down mo vements With brief vertical up and down mo vements below the inside rearview mir ror
th ere ading light forth e driver or the front passenger is switched on and o..
Ab ove the front passenger seat Stretching out a hand abo vethe front
passenger seat By str
etch ing out a hand abo vethe front passenger seat the sear chlight is
switched on. If you withdr awa hand from this area, the sear chlight is
switched o. again. Switc Switc
hing t
hing t he r
he reading light and searc
eading light and searc h light and
h light and
on or
on or o.
o. R
R
eq
eq uir
uir ements:
ements:
R F
For t
or t he r
he r eading light
eading light: :
- The function is available when it is dar k.-
The hand mo vement take s place in the
interaction area below the inside rearview
mir ror.
R F
For t
or t he searc
he searc h light
h light::
- The function is available when it is dar k.-
The hand mo vement take s place in the
interaction area abo vethe front passenger
seat.
- The seat belt on the front passenger seat
must no not
tbe inser ted in the seat belt
buckle. 294
294
MBUX multimedia system

th
e emer gency call and faster transfer of the
accident data.
Measu resfo rre scue, reco very or towing away
can then be initiated in quickl y.
R With a Mercedes-Benz emer gency call, the
accident data is only transfer redto the public
coordination centre with the appr oval of the
cus tomer.
In theev ent of an automatically triggered
emer gency call in which there is no voice con-
ta ct, the accident data is transmitted immedi-
ately tothe public emer gency call centre.
R Should the Mercedes-Benz emer gency call
centre not be available, the 112 emer gency
call is ca rried out automaticall y.Ov Ov
er
ervie
vie w of emerg
w of emerg ency call syst
ency call syst ems
ems Bo
th th e Mercedes-Benz emer gency call system
as well as the 112 emer gency call system (EU
eCall) can help toreduce the time between an
accident and the ar riva l of emer gency services at
th e site of the accident. They help locate an acci-
dent site in places that are di1cult toaccess. Bo
th emer gency call systems can initia tean emer-
ge ncy call automatically (/ page 325) or man-
ual ly ( / page 326).
Only make emer gency calls if you or others are in
need of rescue. Do not make an emer gency call in
th eev ent of a breakdown or a similar situation.
Messag
Messag es on t
es on the display
he display
The following message s appear inthe display of
bo th emer gency call systems:
R SOS NOT READY: theve hicle is not switched
on or the emer gency call system is malfunc-
tioning. This does not necessarily indicate
comple tefailure of the emer gency call system.
Eme rgency calls call still be transmitted.
The display only refers to theve hicle and does
not take account of theav ailability of mobile
phone networ ksand the Mercedes-Benz emer-
ge ncy call centre.
The functional readiness of the emer gency call
system on theve hicle can be seen when the
SOS NOT READY displaydisappears once the
ve hicle is switched on. R
0053: The icon appears in the display during
an active emer gency call.
% Ifth ere is a malfunction in the emer gency call
system (e.g. a fault with the speaker, micro-
phone, airbag, SOS button), a cor responding
message appears on the inst rument displa y. T T
r
r igg
igg er
ering an aut
ing an aut omatic emerg
omatic emerg ency call
ency call R
R
eq
eq uir
uir ements:
ements:
R The vehicle is switched on.
R The star ter battery is su1ciently charge d.
Bo th th e Mercedes-Benz emer gency call system
as well as the 112 emer gency call system (EU
eCall) automatically initia tean emer gency call
aTer:
R Activation of there straint systems su chas air-
bags or seat belt tensioners aTer an accident
The eme rgency call has been made:
R Avo ice connection is established with the
emer gency call centre. MBUX multimedia system
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