sensor MERCEDES-BENZ C-CLASS COUPE 2021 Service Manual

Display messages
Possible causes/consequences and M
MSolutions
If th e display message does not disappear: #
Stop theve hicle in accordance with the tra ffic conditions. #
Clean the windscreen.
Blind Spot Assist currently
unavailable See Owner's
Manual *B
lind Spot Assist is temp 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. #
If necessar y,clean there ar bumper. If the bumper is especially dirty, the sensors in the bumper may be mal‐
functioning.
Blind Spot Assist inopera-
tive *B
lind Spot Assist is malfunctioning. #
Consult a qualified specialist workshop.
Blind Spot Assist not availa-
ble when towing a trailer
See Owner's Manual *W
hen you es tablish the electrical connection tothe trailer, Blind Spot Assist will be una vailable. #
Press the left-hand Touch Control and ackn owledge the display message. Display messages and
warning/indicator lamps 463

Display messages
Possible causes/consequences and M
MSolutions
É Vehicle rising Please wait *T
hevehicle le vel is too lo w.The vehicle will be raised tothe selected vehicle le vel. #
Wait until the display message disappears before pulling away.
É Please reduce speed *Y
ou are driving toofast forth e selected vehicle le vel. #
Toadjust theve hicle le vel,yo u must not drive at speeds greaterth an 60 km/h. #
Toadjust theve hicle le vel during trailer operation, you must not drive at speeds greaterth an 30 km/h.
Parking Assist Manoeu-
vring assistance limited
See Owner's Manual *T
heParking Assist manoeuvring assis tant is temp orarily una vailable or only partially available. #
Clean all sensors of the parking and camera sy stem (/ page373). #
Ifth e display message still appears, consult a qualified specialist workshop.
Parking Assist and
PARKTRONIC inoperative
See Owner's Manual *
Ve hicles with Active Parking Assis t:Ac tive Parking Assist and Parking Assist PARKTRONIC are malfunctioning.
Ve hicles without Active Parking Assis t:Pa rking Assist PARKTRONIC 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. 468
Display messages and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions
Active Brake Assist Func-
tions limited See Owner's
Manual *F
orvehicles with the Driving Assis tance Package, thefo llowing functions may be temp orarily una vailable or limited:
R Active Brake Assi stwith cross-traf fic function
R Evasi veSteering Assist
R PRE‑SAFE ®
PLUS
Ve hicles without the Driving Assistance Package: Active Brake Assi stistemp orarily una vailable or only partially
av ailable. #
Consult a qualified specialist workshop.
Radar sensors dirty See
Owner's Manual *T
heradar sensor sy stem is malfunctioning. Possible causes:
R Dirt on the sensors
R Heavy rain or snow
R Extended country driving wi thout other traf fic, e.g. in the desert
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 all sensors (/ page373). #
Restart the engine. Display messages and
warning/indicator lamps 473

Display messages
Possible causes/consequences and M
MSolutions #
Tryto start theve hicle. #
Ifth eve hicle does not start, consult a qualified specialist workshop.
Cannot start engine See
Owner's Manual *T
hestate of charge ofthe 48 V battery is too lo w.You can no lon gerst art theve hicle. #
Switch off electrical consumers that are not required. #
Connect a suitable charge r appro vedfo r Mercedes-Benz with suf ficient charge output tothe jump-s tart connec‐
tion point of the12 V battery (/ page 388).
The 48 V battery is charge d via thevo ltage con verter in theve hicle.
Motor can be started again *T
he 48 V battery has been charge d automatically via thevo ltage con verter. #
Start theve hicle and drive for a while tocharge the12 V battery and the 48 V batter y. Ty
re pressure moni tor Display messages
Possible causes/consequences and M MSolutions
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 recei ved. The tyre pressure monitoring sy stem is temp orarily una vailable.
The tyre pressure monitoring sy stem will restart automatically as soon as the cause has been rectified. #
Drive on.
Tyre press. monitor inoper-
ative *T
he tyre pressure monitoring sy stem is malfunctioning. Display messages and
warning/indicator lamps 477

Display messages
Possible causes/consequences and M
MSolutions &
WARNING Thereis a risk of an accident if the tyre pressure monitoring sy stem is malfunctioning
The tyre pressure monitoring sy stem cann otissue a warning if there is pressure loss in one or more of the
tyres.
Ty res with insuf ficient tyre pressure may impair the driving characteristics as well as steering and braking. #
Have the tyre pressure monitoring sy stem checked at a qualified specialist workshop. Tyre press. monitor inoper-
ative No wheel sensors
*T
he wheels fitted do not ha vesuitable tyre pressure sensors. The tyre pressure monitoring sy stem 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. Nopressure value is displa yedfo rthe
af fected tyre. #
Have thefa ulty tyre pressure sensor replaced at a qualified specialist workshop.
h Check tyre(s) *T
he tyre pressure in one or more tyres has dropped significantl y.
The wheel position is displa yed. A warning tone also sounds. &
WARNING Risk of an accident due toinsuf ficient tyre pressure
R The tyres can bu rst.
R The tyres can wearexc essively and/or une venly. 478
Displaymessa ges and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions
5 Engine oil pressure Stop
Switch off engine *D
isplay message only for cer tain engines:
The oil pressure is too lo w.
* NO
TEEngine dama gecaused bydriving with insuf ficient oil pressure #
Avoid driving with insuf ficient oil pressure. #
Stop theve hicle immediately in accordance with the traf fic conditions. Do not continue driving. #
Switch off the engine. #
Consult a qualified specialist workshop.
5 Engine oil level cannot be
measured *T
he electrical connection tothe oil le vel sensor has been inter rupte d or the oil le vel sensor is faulty. #
Consult a qualified specialist workshop. Wa
rning and indicator lamps Overview of indicator and
warning lamps Some sy
stems will per form a self-test when the
ignition is switched on. Some indicator and wa
rning lamps may briefly light up or flash. This
behaviour is non-critical. These indicator and
wa rning lamps indicate a malfunction only if they
light up or flash af terth e engine has been star‐
te d or during a journe y. Displ
aymessa ges and warning/indicator lamps 487

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
ï Tr ailer tow hit chwarning
lamp *T
hered trailer hitch warning lamp is lit.
The trailer hitch is not operational. &
WARNING 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 traf fic conditions. Do not continue driving. #
Uncouple the trailer and secure it against rolling away. #
Initiate a new swivel mo vement and do not re-couple the trailer until thewa rning/indicator lamp goes out. #
Notethe messages on the multifunction displa y.Engine
Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
ÿ Coolant warning lamp *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 messages and
warning/indicator lamps 491

:
Switch on headlamps................... 440
Ø Top up AdBlue Emergency op.
in XXX miles See Owner's Manual......... 482
+ Top up coolant See Owner ’s
Manual.................................................. 448
¥ Top up washer fluid ...................... 447
! Turn on the ignition torelease
th e parking brake..................................4 56
d Vehicle is operational Switch
off ignition before exiting..................... .443
É Vehicle rising Please wait............ .468
É Vehicle rising................................4 67
h Warning tyre defect..................... .479
h Wheel sensor(s) missing............... 478
Ø XX,X l Top up AdBlue Switch on
ignition, wait 60 sec. or eng. start
not poss................................................ 483
Ac tive Blind Spot Assi stcur rently
una vailable See Owner's Manual ...........464
Ac tive Blind Spot Assi stinope rative ...... 464 Ac
tive Blind Spot Assi stnot available
when towing a trailer See Owner's
Manual .................................................. 464
Ac tive bonnet malfunction See Own‐
er's Manual........................................... 445
Ac tive Brake Assi stFunctions cur‐
re ntly limited See Owner's Manual ........472
Ac tive Brake Assi stFunctions limited
See Owner's Manual.............................. 473
Ac tive Dis tance Assi stavailable again ...4 60
Ac tive Dis tance Assi stcur rently
una vailable See Owner's Manual ...........460
Ac tive Dis tance Assi stinope rative ........ 460
Ac tive Lane Keeping Assist Camera
view restricted See Owner's Manual..... 465
Ac tive Lane Keeping Assist cur rently
una vailable See Owner's Manual ...........464
Ac tive Lane Keeping Assist inopera‐
tive........................................................ 465 Ac
tive Steering Assist cur rently
una vailable due tomultiple emer‐
ge ncy stops...........................................4 61
Ac tive Steering Assist cur rently
una vailable See Owner's Manual ...........461
Ac tive Steering Assist inoperative ..........461
Ad aptive Highbeam Assist Plus Cam‐
era view restricted See Owner's
Manual................................................... 441
Ad aptive Highbeam Assist Plus cur‐
re ntly una vailable See Owner's Man‐
ual......................................................... 441
Ad aptive Highbeam Assist Plus inop‐
erative.................................................. .441
App lybrake todeselect Park (P)
position................................................. 450
Apply brake toselect R......................... 450
Au xilia rybattery malfunction (red
display message) ...................................4 52 Index
513

Au
xilia rybattery malfunction (white
display message) ...................................4 52
Beginning emer gency stop.....................4 61
Blind Spot Assi stcur rently una vaila‐
ble See Owner's Manual ........................ 463
Blind Spot Assist inope rative ................. 463
Blind Spot Assi stnot available when
to wing a trailer See Owner's Manual .....4 63
Cannot start engine See Owner's
Manual................................................. .477
Check tyre pressures then restart
Ru n Flat Indicator................................. .481
Cruise cont rol and Limiter inope rative.. 458
Cruise control inope rative..................... 458
Cruise control off.................................. 459
Fr ont-passenger airbag disabled See
Owner's Manual....................................4 35
Fr ont-passenger airbag enabled See
Owner's Manual....................................4 35
Hazard warning lamps malfunctioning.. .442 Limi
ter inoperative................................ 459
Limiter passive...................................... 459
Mercedes me connect Services limi‐
te d See Owner's Manual........................4 74
Mo tor can be star ted again...................4 77
N permanently active Risk of vehicle
ro lling .................................................... 451
Only select Park (P) when vehicle is
st ationary.............................................. 450
Pa rking Assist and PARKTRONIC
inoperative See Owner's Manual ...........468
Pa rking Assist Manoeuvring assis‐
ta nce limited See Owner's Manual........ 468
Place theke y in the mar ked space
See Owner's Manual............................. 438
PRE-SAFE inoperative See Owner's
Manual..................................................4 36
Ra dar sensors dirty See Owner's
Manual..................................................4 73
Re duce speed ........................................ 480 Re
versing not poss. Consult workshop.. 451
Risk of vehicle rolling Driver door
open and transmission not in P............. 451
Ru n Flat Indicator inope rative............... .481
Speed limit (winter tyres) XXX km/h..... 461
St op vehicle Lea veengine running
Wa itTransmission cooling .....................452
To shift out of P or N,depress brake
and start engine.................................... 450
To switch off the engine, press
St art/ Stop button for at least 3 sec‐
onds or 3 times. ................................... .447
Tr af fic Sign Assi stCamera view
re stricted See Owner's Manual............. 462
Tr af fic Sign Assi stcur rently una vaila‐
ble See Owner's Manual ........................ 462
Tr af fic Sign Assi stinope rative ............... 462
Tr ansmission Malfunction Stop.............. 451
Ty re press. monitor cur rently una vail‐
able ...................................................... .477 514
Index

Ty
re press. monitor inoperative.............4 77
Ty re press. monitor inoperative No
wheel sensors ........................................ 478
Ty re pressure Check tyres .....................481
Ty re(s) ove rheated................................. 480
Wi thout changing gear, consult work‐
shop......................................................4 51
Display on the windscreen
see Head-up display
Distance control see Active Dis tance Assi stDISTRONIC
DI STRO NIC
see Active Dis tance Assi stDISTRONIC
Door Additional door loc k................................ .74
Locking/unlocking (emergency key)....... .78
Opening (from inside).............................. 75
Un locking (from inside).......................... .75
Door cont rol panel....................................... 16
Dr aw bar
see Tow- bar sy stem
Drive Away Assist ...................................... 225 Drive
Away Assist
see Pr otection against collision
Drive position Enga ging................................................1 59
Drive prog ram display ............................... 15 6
Drive prog rams
see DYNA MIC SELECT
Driver's seat see Seat
Driving abroad Light adjustment (low beam)................. 121
Driving saf ety sy stem
ABS (Anti-lock Braking Sy stem).............1 77
Ac tive Brake Assi st................................ 19 6
Ad aptive brake lights............................. 181
BA S (Brake Assi stSystem).................... 17 7
Cameras............................................... .175
EBD (Electronic Brake forc e Distribu‐
tion).......................................................1 79
ESP ®
Crosswind Assist.......................... 178
ESP ®
trailer stabilisation...................... .179
Overview................................................ 176
Ra dar and ultrasonic sensor s................ 175
Re sponsibility........................................1 75ST
EER CONTROL................................... 17 9
Driving sy stem
DY NA MIC BODY CONTROL.................... 208
Driving sy stem
see 360° Camera
see Active Blind Spot Assi st
see Active Dis tance Assi stDISTRONIC
see Active Emergency Stop Assist
see Active Lane Keeping Assist
see Active Parking Assist
see Active Speed Limit Assi st
see Active Steering Assist
see AIRMATIC
see ATTENTION ASSIST
see Blind Spot Assist
see Cruise control
see Driving saf ety sy stem
see HOLD function
see Limiter
see Parking Assist PARKTRONIC
see Reversing camera
see Traf fic Sign Assi st
Driving tips Driving abroad (low beam light
adjustment).......................................... .121 Index
515