engine MERCEDES-BENZ C-CLASS CABRIOLET 2021 Service Manual

Sy
stem limits
De tection may be restricted in thefo llowing sit‐
uations:
R theve hicle is damaged without impact, e.g. if
an outside mir ror is torn off or the paint is
damaged byakey
R an impact occurs at low speed
R the electric parking brake is not applied Note
s on parking up theve hicle If
yo u lea vetheve hicle par ked up for longer than
six weeks, it may suf fer dama gethro ugh disuse.
The 12V battery may also be impaired or dam‐
aged byheavy discharging.
% Further information can be obtained at a
qu alified specialist workshop. St
andby mode (extension of the star ter bat‐
te ry 's period out of use) St
andby mode function
% This function is not available for all models. If
standby mode is activated, ene rgy loss will be
minimised during extended pe riods of non-oper‐
ation.
St andby mode is characterised bythefo llowing:
R The star ter battery is preser ved.
R The maximum non-operational time appears
inthe media displa y.
R The connection toonline services is inter rup‐
te d.
R The ATA (anti-theft alarm sy stem) is una vaila‐
ble.
R The interior pr otection and tow- aw ay protec‐
tion functions are not available.
R The function for de tecting collisions on a
pa rked vehicle is not available.
If th efo llowing conditions are fulfilled, standby
mode can be activated or deactivated using the
multimedia sy stem:
R The engine is switched off.
R The ignition is switched on.
Exceeding theve hicle's displa yed non-opera‐
tional time may cause incon venience, i.e. it can‐ not be guaranteed
that thest ar ter battery will
re liably start the engine.
The star ter battery must be charge dfirs t in the
fo llowing situations:
R The vehicle's non-operational time must be
ex tended.
R The Battery charge insufficient for standby
mode messa geappears in the media displa y.
% Standby mode is automatically deactivated
when the ignition is switched on.
Ac tivating/deactivating standby mode
Multimedia sy stem:
4 Vehicle 5
î Vehicle settings
5 Standby mode
% This function is not available for all models. #
Activate Oor deacti vate ª the function.
When you activate the function, a prom pt
appears. #
Select Yes.
St andby mode is activated. Driving and parking
167

Fu
nctions of ABS (Anti-lock Braking Sy stem) ABS
regulates the brake pressure in critical driv‐
ing situations:
R During braking, e.g. at maximum full-s top
braking or insuf ficient tyre traction, the
wheels are pr evented from lo cking.
R Vehicle steerability while braking is ensured.
If ABS inter venes when braking, you will feel a
pulsing in the brake pedal. The pulsating brake
pedal can be an indication of hazardous road
conditions and can ser veas a reminder totake
ex tra care while driving.
Sy stem limits
R ABS is active from speeds of appr ox.
5 km/h.
R ABS may be impai red or may not function if a
malfunction has occur red and theye l‐
low ! ABSwarning lamp lights up contin‐
uously in the instrument clus ter af terthe
engine is star ted. Fu
nction of BAS &
WARNING Risk of an accident caused by
a malfunction in BAS (Brake Assi stSys‐
te m)
If BA S is malfunctioning, the braking dis tance
in an emergency braking situation is
increased. #
Dep ress the brake pedal with full force
in emer gency braking situations. ABS
pr eve nts the wheels from locking. The Brake Assist Sy
stem (BAS) supports your
eme rgency braking situation with additional
brake forc e.
If yo u depress the brake pedal quickl y,BA S is
acti vated:
R BAS au tomatical lyboosts the brake pres‐
sure.
R BAS can sho rten the braking dis tance.
R ABS pr events the wheels from locking.
The brakes will function as usual once you
re lease the brake pedal. BAS is deactivated. Fu
nction of ESP ®
(Electronic Stability Pro‐
gr am) &
WARNING Risk of skidding if ESP ®
is
deactivated
If yo u deactivate ESP ®
, ESP ®
cannot car ry
out vehicle stabilisation. #
ESP ®
should on lybe deactivated in the
fo llowing situations. *
NO
TEMercedes-AMG vehicles #
Obser vethe no tes in the Supplement.
Yo u could otherwise failto recognise
dangers. ESP
®
can moni tor and impr ovedriving stability
and traction in thefo llowing situations, within
ph ysical limits:
R When pulling away on wet or slippe rycar ria‐
ge wa ys.
R When braking. 17 0
Driving and pa rking

If
th eve hicle deviates from the direction desired
by the driver, ESP ®
can stabilise theve hicle by
inter vening in thefo llowing ways:
R One or more wheels are braked.
R The engine output is adap ted according to
th e situation.
When ESP ®
is deactivated, theå warning
lamp lights up continuously:
R Driving stability will no lon ger be impr oved.
R The drive wheels could spin.
R ETS/4ETS traction control is still active.
% When ESP ®
is deactivated, you are still assis‐
te dby ESP ®
when braking.
When the÷ warning lamp flashes, one or
se veral wheels has reached its grip limit:
R Adapt your driving style to suit the cur rent
ro ad and weather conditions.
R Do not deactivate ESP ®
.
R Only depress the accelerator pedal as far as
is necessary when pulling away. Deactivate ESP
®
in thefo llowing situations to
impr ovetraction:
R When using snow chains.
R In deep sn ow.
R On sand or gr avel.
% Spinning the wheels results in a cutting
action, which enhances traction.
If th e÷ ESP®
wa rning lamp lights up continu‐
ousl y,ESP ®
is not available due toa malfunction.
Obse rveth efo llowing information:
R Warning and indicator lamps (/ page 485)
R Display messages (/ page 430)
ETS/4ETS (Electronic Traction Sy stem)
ETS/4E TStraction control is pa rtof ESP ®
and
makes it possible topull away and accelerate on
a slippe rycar riag ew ay.
ETS/4ETS can impr ovetheve hicle's traction by
inter vening in thefo llowing ways:
R The drive wheels are braked individually if
they spin. R
More drive torque is transferred tothe wheel
or wheels with traction.
Influence of drive prog rams on ESP ®
The drive prog rams enable ESP ®
to adapt todif‐
fe re nt we ather and road conditions as well as
th e driver's prefer red driving style. Depending on
th e selected drive program, the appropriate
ESP ®
mode will be activated. You can select the
drive programs using theDY NA MIC SELECT
switch (/ page149). Fu
nction of ESP ®
Crosswind Assist ESP
®
Crosswind Assist de tects sudden gu sts of
side wind and helps the driver tokeep theve hi‐
cle in the lane:
R ESP ®
Crosswind Assist is active at vehicle
speeds between appr ox.75 km/h and
200 km/h when driving stra ight ahead or
cornering slight ly.
R The vehicle is stabilised bymeans of individ‐
ual brake application on one side. Driving and parking
171

Fu
nction of ESP ®
trailer stabilisation &
WARNING Risk of accident in poor road
and weather conditions
In poor road and weather conditions, the
trailer stabilisation cannot pr event lu rching of
th eve hicle/trailer combination. Trailers with
a high centre of gr avity may tip over before
ESP ®
de tects this. #
Alw ays adapt your driving style to suit
th e cur rent road and weather condi‐
tions. When driving with a trailer, ESP
®
can stabilise
yo ur vehicle if the trailer begins toswer vefrom
side toside:
R ESP ®
trailer stabilisation is active abo ve
speeds of 65 km/h.
R Slight swerving is reduced bymeans of a tar‐
ge ted, individual brake application on one
side. R
Intheeve nt of se vere swerving, the engine
output is also reduced and all wheels are
braked.
ESP ®
trailer stabilisation may be impaired or
may not function if:
R The trailer is not connec ted cor rectly or is
not de tected prope rly by theve hicle. Ac
tivating/deactivating ESP ®
(Electronic Sta‐
bility Prog ram) Multimedia sy
stem:
4 Vehicle 5
k Assistance 5
ESP
Mercedes‑AMG vehicles: observeth e no tes in
th e Supplement. Otherwise, you may failto rec‐
ognise dangers. #
Activate Oor deacti vate ª the function.
ESP ®
is deactivated if theå ESP®
OFF warn‐
ing lamp lights up continuously in the instrument
clus ter.
Obser vethe information on warning lamps and
display messages which may be shown in the
instrument clus ter. Fu
nction of EBD Elect
ronic Breakforce Distribution (EBD) is char‐
acterised bythefo llowing:
R Monitoring and regulating the brake pressure
on there ar wheels.
R Impr oved driving stability when braking,
especially on bends. Fu
nction of STEER CONT ROL ST
EER CONTROL assi stsyo uby transmitting a
noticeable steering forc eto thesteering wheel in
th e direction requ ired forve hicle stabilisation.
This steering recommendation is given in thefo l‐
lowing situations:
R both right wheels or bo thleft wheels are on a
we t or slippe ryroad sur face when you brake
R theve hicle starts toskid
Sy stem limits
ST EER CONTROL may be impaire d or may not
function in thefo llowing situations:
R ESP ®
is deactivated. 17 2
Driving and pa rking

R
ESP ®
is malfunctioning.
R The steering is malfunctioning.
If ESP ®
is malfunctioning, you will be assis ted
fur ther by the electric po werst eering. HOLD function
HOLD function
The HOLD function holds
theve hicle at a stand‐
st ill without requ iring youto depress the brake
pedal, e.g. while waiting in traf fic.
The HOLD function is only an aid. The responsi‐
bility forth eve hicle safely standing still remains
with the driver.
Sy stem limits
The HOLD function is only intended toprov ide
assis tance when driving and is not a su fficient
means of safeguarding theve hicle against rolling
aw ay when stationar y.
R The incline must not be greater than 30%. Ac
tivating/deactivating the HOLD function &
WARNING 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 llaw ay:
R Ifth ere is a malfunction in the sy stem or
in the po wer supp ly.
R Ifth e HOLD function is deactivated by
depressing the accelera tor pedal or brake
pedal, e.g. byave hicle occupant. #
Alw ays secure theve hicle against roll‐
ing away before you lea veit. Re
quirements:
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 engine is running or has been au tomati‐
cally switched off bythe ECO start/ stop
function. R
The electric parking brake is released.
R Active Dis tance Assi stDISTRONIC is deacti‐
va ted.
R The transmission is in position h,kori.
Ac tivating the HOLD function #
Dep ress the brake pedal, and af ter a short
time quickly depress fur ther until theë
display appears in the multifunction displa y. #
Release the brake pedal.
Deactivating the HOLD function #
Depress the accelerator pedal topull away.
or #
Depress the brake pedal until theë dis‐
play disappears from the multifunction dis‐
pla y.
The HOLD function is deactivated in thefo llow‐
ing situations:
R Active Dis tance Assi stDISTRONIC is acti va‐
te d.
R The transmission is shif tedto position j. Driving and parking
17 3

R
Sensitive: higher system sensitivity. The
driver is warned earlier and the attention
le ve l de tected byATTENTION ASSIST is adap‐
te d according ly.
If dr owsiness or increasing lapses in concentra‐
tion are de tected, theATTENTION ASSIST: Take
a break! warning appears in the Instrument Dis‐
pla y.Yo u can ackn owledge the message and
ta ke a break where necessar y.Ifyo u do not take
a break and ATTENTION ASSIST continues to
de tect increasing lapses in concentration, you
will be warned again af ter a minimum of
15 minutes. Yo
u can ha vethefo llowing status information for
AT TENTION ASSIST displa yed in the assis tance
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.
If AT TENTION ASSIST is unable tocalculate the
attention le vel and cannot issue a warning, the
System suspended messageappears.
If a warning is given in the Instrument Displa y,
th e multimedia sy stem of fers to sear chfor a rest
area. You can select a rest area and start naviga‐
tion tothis rest area. This function can be activa‐
te d and deactivated in the multimedia sy stem.
If AT TENTION ASSIST is deactivated, theÛ
symbol appears in the assis tance graphic in the
Instrument Display when the engine is running.
AT TENTION ASSIST is activated automatically
when the engine is re-sta rted. The last selected
sensitivity le velre mains stored. Sy
stem limits
AT TENTION ASSIST is active in the 60 km/h to
200 km/h speed range.
Pa rticularly in thefo llowing situations, ATTEN‐
TION ASSIST only functions in a restricted man‐
ner and warnings 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 face or po tholes).
R Ifth ere is a strong side wind.
R Ifyo u adopt a sporty driving style (high cor‐
nering speeds or high rates of acceleration).
R IfAc tive Steering Assist is activated and
active .
R Ifth e time has been set incor rectly.
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 Ifyo u swit choff the engine. Driving and parking
175

R
Ifyo u unfas tenyo ur seat belt and open the
driver's door (e.g. tochange drivers or take a
break).
Setting ATTENTION ASSI ST
Multimedia sy stem:
4 Vehicle 5
k Assistance
5 ATTENTION ASSIST
Setting options #
Select Standard, SensitiveorOff.
Suggesting a rest area #
Select Suggest rest area .#
Activate Oor deacti vate the function ª.
If AT TENTION ASSIST de tects fatigue or
increasing la ckof attention, it suggests a
re st area in the vicinit y. #
Select a sugges tedre st area: you are gui‐
ded tothe selected rest area. Cruise cont
rol and limiter Fu
nction of cruise control
Cruise cont rolre gulates the speed totheva lue
selec tedby the driver.
If yo u accelerate toove rtake, forex ample, the
st ored speed is not dele ted. If youre mo veyour
fo ot from the accelerator pedal af terove rtaking,
cruise control will resume speed regulation back
to thestored speed.
Yo u can store any speed abo ve20 km/h up to
th e maximum design speed or up tothe set win‐
te r tyre limit.
Obser vethe no tes on driving sy stems and your
re sponsibility; you may otherwise failto recog‐
nise dangers (/ page 168).
Me rcedes‑AMG vehicles: cruise control is avail‐
able up toa maximum speed of 250 km/h.
Displ ays on the multifunction display
R h (gre y): cruise cont rol is selec ted but
not yet acti vated.
R h (green): cruise control is active. A
stored speed appears along with theh dis‐
pla y.
% The segments extending from the cur rent
st ored speed tothe end of the scale, or to
th e set winter tyre limit, light up in the
speedome ter.
Sy stem limits
Cruise control may be unable tomaintain the
st ored speed on uphill gradients. The stored
speed is resumed when the gradient evens out.
Change into a lo werge ar in good time on long
and steep downhill gradients. Take particular
no te ofthis when driving a laden vehicle. By
doing so, you will make use of the engine's brak‐
ing ef fect. This relie vesth e load on the brake
sy stem and pr events the brakes from overheat‐
ing and wearing tooqu ickl y.
Do not use cruise control in thefo llowing situa‐
tions:
R In traf fic situations whi chrequ ire frequent
ch anges of speed, e.g. in heavy traf fic, on
winding roads. 176
Driving and pa rking

cle and
there is a risk of a lateral collision, a
wa rning is issued and the segments light up in
colour in the displa y.
The segment colour changes depending on the
dis tance tothe de tected obs tacle:
R Yello w: appr oximately 30 - 60 cm
R Red:less than appr oximately 30 cm
In order for lateral front or rear segments tobe
displa yed, theve hicle must firs t tr ave l a dis tance
of at least half of theve hicle length. Once the
ve hicle has tr avelled the length of theve hicle, all
of the lateral front and rear segments can be dis‐
pla yed. Pa
rking Assist PARKTRONIC display: vehicles
without a 360° Camera
1 Operational front and rear
2 Operational front, rear and sides
3 Obstacle de tected at the front right (yellow)
and rear (red) Pa
rking Assist PARKTRONIC display: vehicles
with a 360° Camera
1 Operational front and rear
2 Operational front, rear and sides
3 Obstacles de tected at the front right (red)
Sa ved obs tacles on the sides are dele ted in the
fo llowing situations, forex ample:
R You park theve hicle and switch off the igni‐
tion.
R You open the doors.
Af terth e engine is restar ted, obs tacles on the
sides must be de tected again before a new
wa rning can be issued. 212
Driving and pa rking

Instrument display
overview 1
Speedome ter
The segments on the speedome ter indica te
th est atus of thefo llowing sy stems: cruise
control / limiter / Active Dis tance Assi st
DISTRONIC
2 Outside temp erature
3 Time 4
Area for additional values (e xamp le:rev
counter): rev counter / navigation / ECO
display / consum ption / G-me ter / date
The fuel supply will be inter rupted toprotect
th e engine when there d mark on therev
counter (o verrev ving range) is reached.
5 Coolant temp erature display During normal operation,
the coolant tem‐
perature display is permitted torise to
12 0°C.
Ve hicles with 48 V on-board electrical sys‐
te m: POWER and CHARGE displ ays (electri‐
cal drive support and recuperation po wer of
th e electric mo tor)
6 Selected drive program Instrument display and on-board computer
227

Vo
ice command Function
Scent menu To
display fragrance settings
Energy flow To
display energy flow settings
Ionisation menu To
display ionisation settings
Climate control menu To
display climate control settings
Automatic climate control driver on To
switch on the automatic climate control settings on the driver's side
Light menu To
display light settings
Massage menu To
display massage settings
Massage driver's seat on To
switch on the massage function forth e driver's seat
Massage driver's seat off To
switch off the massage function forth e driver's seat
Outside temperature To
display the outside temp erature
Engine data Displaying engine data
Seats menu To
display seat adjustment settings
Seat heating front passenger level "2" To
set the seat heating forth e front passenger seat toleve l 2 LINGU
ATRO NIC 245