steering MERCEDES-BENZ C-CLASS COUPE 2021 Repair Manual

To
avo id damage totheve hicle, deactivate
th ese sy stems in thefo llowing or similar sit‐
uations: #
During towing #
In a car wash 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.
* NO
TEDama getotheve hicle due to tow‐
ing away incor rectly #
Obser vethe instructions and no tes on
to wing away. Ve
hicles with manual transmission Pe
rm itted towing me thods
Bo th axles on
th e ground Ye
s, maximum 50 km at
50 km/h
Fr ont axle
ra ised Ye
s, maximum 50 km at
50 km/h
Re ar axle
ra ised Ye
s, maximum 50 km at
50 km/h Ve
hicles with automatic transmission Pe
rm itted towing me thods
Bo th axles on
th e ground Ye
s, maximum 50 km at
50 km/h
Fr ont axle
ra ised No
Re ar axle
ra ised Ye
s, if thesteering wheel is
fi xe d in the cent reposition
with a steering wheel lock 4MATIC
vehicles Pe
rm itted towing me thods
Bo th axles on
th e ground Ye
s, maximum 50 km at
50 km/h
Fr ont axle
ra ised No
Re ar axle
ra ised No To
wing with a raised axle: towing should be
per form ed byato wing compan y. To
wing theve hicle with bo thaxles on the
gr ound #
Obser vethe no tes on the permitted towing
me thods (/ page 390). #
Make sure that the battery is connected and
ch arge d.
Obser vethefo llowing points when the battery is
dischar ged:
R the engine cann otbe star ted Breakdown assis
tance 391

&
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.
R the brake sy stem or po werst eering sys‐
te m is malfunctioning.
R the energy supply or the on-board electri‐
cal sy stem is malfunctioning.
When your vehicle is then towe daw ay, signif‐
icantly more ef fort may be requ ired tosteer
and brake than is no rmally requ ired. #
Use a tow bar. #
Make sure that thesteering wheel can
mo vefreely before towing theve hicle
aw ay. *
NO
TEDama gedue toexcessive tracti ve
po wer If
yo u pull away sharpl y,the tractive po wer
may be too high and theve hicles could be
damaged. #
Pull away slowly and smoo thly. Loading the
vehicle for transport #
Obser vethe no tes on towing away
( / page 391). #
Connect theto w bar totheto wing eye in
order toload theve hicle.
% You can also attach theto w bar tothe trailer
hitch. #
Vehicles with automatic transmission:
shift the automatic transmission toposition
i.
% Ve
hicles with automatic transmission:
th e automatic transmission may be loc ked in
position jintheeve nt of dama getothe
electrical sy stem. Toshift toi , pr ovide the on-board electrical sy
stem with po wer
( / page 388). #
Load theve hicle onto the transpor ter. #
Vehicles with automatic transmission:
shift the automatic transmission toposition
j. #
Use the electric parking brake tosecure the
ve hicle against rolling away. #
Only secure theve hicle bythe wheels.
Ve hicles with ADS PLUS (Adaptive Damping
Sy stem PLUS) &
WARNING Risk of an accident when
transporting vehicles with Adaptive
Damping Sy stem PLUS
When transporting vehicles with Adaptive
Damping Sy stem PLUS, theve hicle/trailer
combination may begin torock andstart to
skid. #
When transporting, ensure that:
R theve hicle has been loaded onto
th e transpor ter cor rectly Breakdown assis
tance 393

ing condition (/
page 401). Observethe
no tes on tyre temp erature (/ page 400).
% The values displa yed in the on-board com‐
puter may deviate from those of the tyre
pressure gauge as they referto sea le vel.At
high ele vations, the tyre pressure values
indicated bya pressure gauge are higher
th an those shown bythe on-board computer.
In this case, do not reduce the tyre pressure.
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 all
of the wheels (/ page 400).
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 tyre pressures as new refer-
ence values? message is shown in the multi‐
function displa y. #
Torestart, 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.
Be sure toalso pay attention tothefo llowing
re lated topic:
R Notes on tyre pressure (/ page 400) Ty
re pressure loss warning sy stem Fu
nction of the ty repressure loss warning
sy stem
The tyre pressure loss warning sy stem warnsthe
driver bymeans of display messa ges when there
is a se vere tyre pressu reloss.
Sy stem limits
The sy stem may be impaired or may not function
particular lyin thefo llowing situations:
R incor rectly set tyre pressure
R sudden pressure loss caused, forex ample,
by afo re ign object penetrating the tyre
R steady pressure loss in se veral tyres
The sy stem has a restricted or del ayed function
particularly in thefo llowing situations:
R poor ground cond itions, e.g. snow or gr avel
R driving with snow chains
R when adopting a very sporty driving style
with high cornering speeds or sudden accel‐
eration
R driving with a very heavy or lar getrailer Wheels and tyres
403

R
driving with a high load
The tyre pressure loss warning 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 and tocheck
it.
Be sure toalso obse rveth efo llowing fur ther
re lated subjects:
R Notes on tyre pressure (/ page 400)
R Display messages about the tyres
(/ page 477)
Rest arting the ty repressure loss warning
sy stem
Requ irements:
R The recommended tyre pressure is cor rectly
set forth ere spective operating status on all
wheels.
Re start the tyre pressure loss warning 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 Run Flat Indicator active Restart: press
Touch Control message is shown in the mul‐
tifunction displa y. #
Tobegin restart, press Touch Control on the
left-hand side of thesteering wheel.
The Tyre pressure now OK? message is
shown in the multifunction displa y. #
Select Yes. #
Toconfirm restart, press Touch Control on
th e left-hand side of thesteering wheel.
The Run Flat Indicator restarted message is
shown in the multifunction displa y.
Af teryo u ha vedriven for a few minutes, the
tyre pressu reloss warning sy stem monitors
th e set tyre pressures of all the tyres.
Be sure toalso pay attention tothefo llowing
re lated topic:
R Notes on tyre pressure (/ page 400) Wheel
change Note
s on selecting, fitting and replacing
tyres *
NO
TEMercedes-AMG vehicles #
Obser vethe no tes in the Supplement.
Yo u could otherwise failto recognise
dangers. &
WARNING Risk of inju rythro ugh incor‐
re ct sizes of wheels and tyres
If wheels and tyres of the wrong size are fit‐
te d, the wheel brakes or components in the
brake sy stem and in the wheel suspension
may be damaged. #
Alw aysre place wheels and tyres with
th ose that fulfil the specifications of the
original part.
Fo r wheels, pay attention tothefo llowing:
R Designation
R Type 404
Wheels and tyres

Display messages
Possible causes/consequences and M
MSolutions #
Do not couple up the trailer. Drive on without the trailer. No tethere duced ground clearance due tothe
unlo cked ball nec k. #
Consult a qualified specialist workshop.
*T he trailer hitch will not be operational when theve hicle is stationar y. #
Uncouple the coupled trailer and secure it against rolling away. #
Ifth e ball neck has been folded in: unlockthe ball neck (/ page 227). #
Swivel the ball neck into the end position manually and let it engage. #
Ifth e ball neck has been folded out: unlockthe ball neck (/ page 227). #
Swivel the ball neck beneath the bumper manually and let it engage.
If th e display message does not disappear, the trailer hitch is malfunctioning and the ball neck is not loc ked. #
Do not couple up the trailer. Drive on without the trailer. No tethere duced ground clearance due tothe
unlo cked ball nec k. #
Consult a qualified specialist workshop.
Ù Steering malfunction
Increased physical effort
See Owner's Manual *T
he po werst eering assis tance is malfunctioning. &
WARNING Risk of an accident due toaltered steering characteristics
If th e po wer assi stance of thesteering fails partially or comple tely, you will need touse more forc eto steer. #
If safe steering is possible, drive on carefully. 444
Displaymessa ges and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions #
Visit or consult a qualified specialist workshop immediatel y. Ù
Steering malfunction Stop
immediately See Owner's
Manual *T
hesteering is malfunctioning. Steering capability is significant lyimpaired. &
WARNING Risk of accident if steering capability is impaired
If th esteering does not function as intended, theve hicle's operating saf ety is jeopardised. #
Pull over and stop theve hicle safely as soon as possible, paying attention toroad and traf fic conditions.
Do not continue driving under any circums tances. #
Consult a qualified specialist workshop. Active bonnet malfunction
See Owner's Manual
*T
he active bonnet (pedestrian pr otection) is malfunctioning or inoperative af ter having already been triggered. #
Consult a qualified specialist workshop.
C *A
t least one door is open. #
Close all doors.
M *T
he bonnet is open. &
WARNING Risk of accident due todriving with the bonn etunlo cked
The bonn etmay open and block your vie w. Displ
aymessa ges and warning/indicator lamps 445

Display messages
Possible causes/consequences and M
MSolutions
Speed limit (winter tyres)
XXX km/h *Y
ou ha vereached the maximum permissible stored speed for winter tyres. It is not possible toexceed this speed.
Active Steering Assist cur-
rently unavailable See Own-
er's Manual *A
ctive Steering Assist is temp orarily una vailable.
The ambient conditions are outside the sy stem limits (/ page193).
As soon as the ambient conditions are within the sy stem limits, the sy stem will become available again. #
Drive on. #
If necessar y,clean the windscreen in the camera's field of vision. #
Check the tyre pressure if necessar y.
Active Steering Assist inop-
erative *A
ctive Steering Assist is malfunctioning. Active Dis tance Assi stDISTRONIC remains available. #
Consult a qualified specialist workshop.
Active Steering Assist cur-
rently unavailable due to
multiple emergency stops *A
ctive Steering Assist is temp orarily una vailable due tomultiple emergency stops. #
Take ove rth esteering and stop in accordance with the tra ffic conditions. #
Swit chthe ignition off and switch it back on.
Ac tive Steering Assist is available once more.
Beginning emergency stop *Y
our hands are not on thesteering wheel. An emer gency stop is being initiated (/ page195). #
Put your hands back on thesteering wheel.
Yo u can cancel the deceleration at any time byper form ing one of thefo llowing actions:
R Steering Display messages and
warning/indicator lamps 461

Display messages
Possible causes/consequences and M
MSolutions
R Braking or accelerating
R Deactivating Active Dis tance Assi stDISTRONIC
Ø *A
ctive Steering Assist has reached the sy stem limits (/ page193).
Yo u ha venot steered independently for a considerable period of time. #
Take ove rth esteering and drive on in accordance with the traf fic conditions.
Traffic Sign Assist currently
unavailable See Owner's
Manual *T
raffic Sign Assist is temp orarily una vailable.
Once the cause of the problem is no longer present, the sy stem will be available again. #
Drive on. #
Ifth e display message does not disappear, stop theve hicle safely and clean the windscreen.
Traffic Sign Assist inopera-
tive *T
raffic Sign Assist is malfunctioning. #
Stop theve hicle in accordance with the tra ffic conditions and restart the engine. #
Ifth e display message still appears, consult a qualified specialist workshop.
Traffic Sign Assist Camera
view restricted See Own-
er's Manual *T
he camera view is restricted. Possible causes:
R Dirt on the windscreen in the camera's field of vision
R Heavy rain, snow or fog
Driving sy stems and driving saf ety sy stems may be malfunctioning or temp orarily una vailable.
Once the cause of the problem is no longer present, the driving sy stems and driving saf ety sy stems will be available
again. 462
Display messages and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions
Active Blind Spot Assist
currently unavailable See
Owner's Manual *A
ctive Blind Spot Assi stistemp orarily una vailable.
The sy stem limits ha vebeen reached (/ page 202).
Once the cause of the problem is no longer present, the sy stem will be available again. #
Drive on.
or #
Ifth e display message does not disappear, stop theve hicle in accordance with the tra ffic conditions and restart
th e engine.
Active Blind Spot Assist
inoperative *A
ctive Blind Spot Assi stis malfunctioning. #
Consult a qualified specialist workshop.
Active Blind Spot Assist
not available when towing
a trailer See Owner's Man-
ual *W
hen you es tablish the electrical connection tothe trailer, Active Blind Spot Assi stwill be una vailable. #
Press the left-hand Touch Control and ackn owledge the display message.
Active Lane Keeping Assist
currently unavailable See
Owner's Manual *A
ctive Lane Keeping Assist is temp orarily una vailable.
The ambient conditions are outside the sy stem limits (/ page 205).
As soon as the ambient conditions are within the sy stem limits, the sy stem will become available again.
Ve hicles with Active Steering Assis t:the camera view may be limited bythe windscreen. #
Drive on. 464
Display messages and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions
Ve hicles with Active Steering Assis t:ifth e display message does not disappear: #
Stop theve hicle in accordance with the tra ffic conditions. #
Clean the windscreen.
Active Lane Keeping Assist
inoperative *A
ctive Lane Keeping Assist is malfunctioning. #
Consult a qualified specialist workshop.
Active Lane Keeping Assist
Camera view restricted
See Owner's Manual *
Ve hicles without Active Steering Assis t:the camera view is restricted.
Po ssible causes:
R Dirt on the windscreen in the camera's field of vision
R Heavy rain, snow or fog
Driving sy stems and driving saf ety sy stems may be malfunctioning or temp orarily una vailable.
Once the cause of the problem is no longer present, the driving sy stems and driving saf ety sy stems will be available
again.
If th e display message does not disappear: #
Stop theve hicle in accordance with the tra ffic conditions. #
Clean the windscreen. Display messages and
warning/indicator lamps 465