MERCEDES-BENZ C-CLASS CABRIOLET 2021 Owners Manual

Lights
Display messages
Possible causes/consequences and M
MSolutions
: Left dipped beam (examp le) *T
he cor responding light source is defective. #
Drive on carefully. #
Consult a qualified specialist workshop immediatel y.
% LED light sources: the display message forth e cor responding light appears only when allthe light-emitting
diodes in the light are faulty.
: Malfunction See Owner's
Manual *T
heexterior lighting is malfunctioning. #
Consult a qualified specialist workshop.
* Ve hicles with a trailer hitch: a fuse may haveblown. #
Stop theve hicle in accordance with the tra ffic conditions. #
Check the fuses and replace them if necessary (/ page 391).
:
Automatic driving lights
inoperative *T
he light sensor for auto matic driving lights is malfunctioning. #
Consult a qualified specialist workshop. 438
Display messages and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions
: Active Light System inoper-
ative *T
he active headlamp s are malfunctioning. #
Consult a qualified specialist workshop.
: Switch on headlamps *Y
ou are driving without lo w-beam headlamps. #
Turn the light switch totheL orà position.
:
Switch off lights *Y
ou are leaving theve hicle and the lights are still switched on. #
Turn the light switch totheà position.
: Intelligent Light System
inoperative *T
he Intelligent Light Sy stem is malfunctioning. The lighting sy stem continues tofunction proper lywithout the func‐
tions of the Intelligent Light Sy stem. #
Consult a qualified specialist workshop. Display messages and
warning/indicator lamps 439

Display messages
Possible causes/consequences and M
MSolutions
Adaptive Highbeam Assist
Plus currently unavailable
See Owner's Manual *A
daptive Highbeam Assist Plus is temp orarily una vailable.
The sy stem limits ha vebeen reached (/ page124).
Once the cause of the problem is no longer present, the sy stem will be available again. The Adaptive Highbeam
Assist Plus available again display message will appear. #
Drive on. #
Operate the high beam manually until Adaptive High Beam Assist Plus is available again.
Adaptive Highbeam Assist
Plus inoperative *A
daptive Highbeam Assist Plus is malfunctioning. #
Consult a qualified specialist workshop.
Adaptive Highbeam Assist
Plus Camera view restric-
ted See Owner'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.
If th e display message does not disappear: #
Stop theve hicle in accordance with the tra ffic conditions. #
Clean the windscreen. 440
Displaymessa ges and warning/indicator lamps

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
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. #
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. Displ
aymessa ges and warning/indicator lamps 443

Display messages
Possible causes/consequences and M
MSolutions
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. #
Neverre lease the bonn etwhen driving. #
Before every trip, ensure that the engine bonn etis loc ked. #
Stop theve hicle immediately in accordance with the traf fic conditions. #
Close the bonn et.
N *T
he boot lid is open. &
DANG ER Risk of exhaust gas poisoning
Combustion engines emit poisonous exhaust gases such as carbon monoxide. Exhaust gases can enter the
ve hicle interior if the boot lid is open when the engine is running, especially if theve hicle is in motion. #
Alw ays switch off the engine before opening the boot lid. #
Never drive with the boot lid open. #
Close the boot lid. 444
Displaymessa ges and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions
_ Rear left seat backrest not
locked (Example) *T
he seat backrest of the cor responding seat is not engaged. #
Foldthe seat backrest back until it engages.
_ Front left seat backrest not
locked (exa mp le) *T
he seat backrest of the cor responding front seat is not engaged. #
Foldthe seat backrest back until it engages.
¥ Top up washer fluid *T
hewasher fluid le vel in thewa sher fluid reser voir has dropped below the minimum. #
Top up thewa sher fluid (/ page 361). Display messages and
warning/indicator lamps 445

Engine
Display messages
Possible causes/consequences and M
MSolutions
To switch off the engine,
press Start/Stop button
for at least 3 seconds or 3
times. *Y
ou ha vepressed thest art/ stop button while theve hicle is in motion. #
Information about switching off the engine while driving (/ page138).
+ Top up coolant See Own-
er’s Manual *T
he coolant le vel is too lo w.
* NO
TEEngine dama gedue toinsuf ficient coolant #
Avoid long journe yswith insuf ficient coolant. #
Add coolant (/ page 361). #
Have the engine cooling sy stem checked at a qualified specialist workshop.
ÿ
Coolant Stop vehicle
Switch engine off *T
he coolant is too hot. #
Stop theve hicle immediately in accordance with the traf fic conditions and switch off the engine. 446
Displaymessa ges and warning/indicator lamps

Display messages
Possible causes/consequences and M
MSolutions &
WARNING Risk of bu rns when opening the bonn et
If yo u open the bonn etwhen the engine has overheated or when there is a fire inthe engine compartment, the
fo llowing situations may occur:
R You could come into contact with hot gases.
R You could come into contact with other hot, escaping operating fluids. #
Before opening the bonn et, allow the engine tocool down. #
Intheeve nt of a fire inthe engine compartment, keep the bonn etclosed and call thefire service. #
Wait until the engine has cooled down. #
Make sure that the air supply tothera diator is not obstructed. #
Avoiding high loads on the engine, drive tothe nearest qualified specialist workshop. In doing so, ensure that
th e coolant temp erature display remains below 120°C.
ÿ *T
hefan mo tor is defective. #
Avoiding high loads on the engine, drive tothe nearest qualified specialist workshop. In doing so, ensure that
th e coolant temp erature display remains below 120 °C. Displ
aymessa ges and warning/indicator lamps 447