2021 MERCEDES-BENZ C-CLASS CABRIOLET trailer

Display messages
Possible causes/consequences and M
MSolutions
Hazard warning lamps mal-
functioning *T
he hazard warning lamp switch is malfunctioning. #
Consult a qualified specialist workshop. Ve
hicle Display messages
Possible causes/consequences and M MSolutions
d Vehicle is operational
Switch off ignition before
exiting *Y
ou are leaving theve hicle in a ready-to-drive state. #
When you lea vetheve hicle, switch off the ignition, secure theve hicle against rolling away and take theke y with
yo u. #
Ifyo u do not lea vetheve hicle, switch off the electrical consumers, e.g. the seat heating. Otherwise, the12 ‑V
battery may discharge and starting the engine may be possible only with the help of a second battery (jump
st art).
ï
Check trailer hitch lock *T
he trailer hitch is not operational during a journey with a trailer. &
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. Display messages and
warning/indicator lamps 441

Display messages
Possible causes/consequences and M
MSolutions #
Initiate a new swivel mo vement (/ page 220). #
When the display message disappears, couple up the trailer and drive on.
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.
*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 220). #
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 220). #
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. 442
Displaymessa ges and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions #
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.
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 (/ page195).
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. 462
Display messages and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions
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 (/ page198).
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.
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 Displ
aymessa ges and warning/indicator lamps 463

Display messages
Possible causes/consequences and M
MSolutions
É Vehicle rising *Y
our vehicle is adjusting tothe le velyo u ha veselected.
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 (/ page 368). #
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. 466
Display messages and warning/indicator lamps

Instrument display (standard)
Wi
descreen co ckpit instrument displ ay Depending on
the display setting, the positions
of the indicator lamps on the instrument display
may dif fer from theex ample shown.
Indicator and warning lamps:
6 Re
stra int sy stem (/ page 487)
ü Seat belt (/
page 487)
ï Trailer hit ch (/page 488)
Ù Powe rst eering (/ page 488)
ÿ Coolanttemp erature (/ page 489)
; Engine diagnostics (/
page 489)
% Ve
hicles with a diesel engine: pre‐
gl ow
# Electrical
fault (/ page 489)
8 Re
ser vefuel with fuel filler flap loca‐
tion indicator (/ page 489)
! Elect
ric pa rking brake (red)
(/ page 492)
! Electric parking brake (yellow)
(/
page 492)
J Brakes (yellow) (/
page 492)
J Brakes (red) (/
page 492) L
Distance warning (/ page 494)
ä AIRMATIC (/ page 494)
ä DYNA MIC BODY CONTROL
(/ page 494)
! ABS (/
page 495)
÷ ESP®
(/ page 495)
å ESP®
OFF (/ page 495)
h Ty
re pressure monitoring sy stem
(/ page 498)
T St
anding lights (/ page119)
L Low beam (/
page119)
K High beam (/
page121)
#! Tu
rn signal lights (/ page121)
R Re
ar fog light (/ page119) 486
Displaymessa ges and warning/indicator lamps

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 489

DIRECT SELECT le
ver
Engaging drive position........................ .152
Engaging neutral................................... .151
Engaging pa rkposition.......................... 15 2
Engaging pa rkposition automatically....1 52
Engaging reve rsege ar........................... .151
Fu nction................................................ 15 0
Display (care) ............................................ .369
Display (multimedia sy stem)
Settings................................................. 256
Display (on-boa rdcompu ter)
Displ ays on the multifunction displa y.... 229
Displ aymessage
Calling up (on-board compu ter)............ .430
No tes....................................................4 30
Display messages ¯ - - - km/h ..................................... 457
ç - - - km/h ..................................... 458
È - - - km/h ..................................... 457
# 12V battery See Owner's Man‐
ual......................................................... 472K
12V battery See Owner's Man‐
ual......................................................... 437
Û 48 V battery See Owner's Man‐
ual..........................................................4 74
: Active Light Sy stem inoperative... 439
¯ AdBlue sy stem fault Emer. op.:
max. XXX mphSt art not poss. in XXX
miles .................................................... .482
¯ AdBlue sy stem fault Emer‐
ge ncy op. in XXX km See Owner's
Manual.................................................. 481
¯ AdBlue sy stem fault Engine
st art not possible................................. .482
¯ AdBlue sy stem fault See Own‐
er's Manual ............................................ 481
5 Add 1 litre engine oil when
next refuelling....................................... 483
é ATTENTION ASSIST inoperative ....456
é ATTENTION ASSIS T:Take a
break!....................................................4 56:
Automatic driving lights inoper‐
ative...................................................... 438
Á Change key bat teries ...................4 34
J Checkbrake fluid le vel................. 455
5 Check engine oil le vel when
next refuelling....................................... 483
ï Checktrailer hitch lo ck................ 441
h Check tyre(s) ................................ 476
! Clean the fuel filter ...................... 448
J Close boot separator .................... 437
K Convertible Top Operation pos‐
sible to60 km/h................................... 436
ÿ Coolant Stop vehicle Switch
engine off..............................................4 46
! currently una vailable See Own‐
er's Manual ............................................ 467
÷ currently una vailable See Own‐
er's Manual .......................................... .468
5 Engine oil le vel cannot be
measured .............................................. 485 Index
509