2021 MERCEDES-BENZ C-CLASS CABRIOLET engine coolant

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

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

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
R The coolant pump is faulty
If th ere is an additional warning tone, the coolant temp erature has exceeded 120°C. &
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. #
Stop theve hicle immediately in accordance with the traf fic conditions and switch off the engine. Do not continue
driving. #
Notethe messages on the multifunction displa y.
If th e coolant temp erature display is at the lo wer end of thete mp erature scale: #
Consult a qualified specialist workshop.
If th e coolant temp erature display is at the upper end of thete mp erature scale: #
Exit theve hicle and keep a safe dis tance from it until the engine has cooled down. #
Check the coolant le vel (/ page 361). 490
Display messages and warning/indicator lamps

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions #
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 the
coolant temp erature display remains below 120°C.
; Engine diagnosis warning
lamp *T
he yellow engine diagno stics warning lamp is lit while the engine is running.
A malfunction has occu rred in the engine, theex haust sy stem or the fuel sy stem.
The emissions limit value may ha vebeen exceeded and the engine may be running in eme rgency operation mode. #
Have theve hicle checked as soon as possible at a qualified specialist workshop.
Ve hicles with a diesel engine: the fuel tank may ha vebeen run dr y. #
Start the engine thre eto four times af terre fuelling.
If th eye llow engine diagnosis warning lamp goes out, emer gency operation mode is cancelled. The vehicle need
not be checked.
#
Elect rical fault warning
lamp *T
hered elect rical fault warning lamp is lit.
There is a fault in the electrics. #
Notethe messages on the multifunction displa y. Displ
aymessa ges and warning/indicator lamps 491

City lighting
................................................ 124
Cleaning see Care
Climate control Activating/deactivating the A/C
function (cont rol panel)........................ .134
Ac tivating/deactivating the synchro‐
nisation function (cont rol panel)............ 13 4
Air-reci rculation mode.......................... .134
Au tomatic control.................................. 13 4
Demi sting the windscreen..................... 13 3
Demi sting windo ws............................... 13 4
Fr ont air vents....................................... 13 5
Ionisation............................................... 13 4
No te...................................................... 13 3
Re ar air vents....................................... .135
Setting the air distribution..................... 13 3
Setting the air flow ................................. 13 3
Setting theve hicle interior temp era‐
ture........................................................ 13 3
Switching on/of f................................... 13 3
Switching there ar wind owheater
on/off...................................................1 33
THERMATIC control pane l...................... 13 3
THERMOTRONIC contro l panel..............133 Ve
ntilating theve hicle (con venience
opening).................................................. 90
Co ckpit
Overview................................................... 6
Co ffee cup symbol
see ATTENTION ASSIST
Collision de tection (pa rked vehicle)
Information............................................ 16 6
COMAND Online see Multimedia sy stem
COMAND Touch
Managing devices.................................. 261
Combination switch .................................. 121
Compass................................................... .294
Compu ter
see On-board computer
Connection status
Displ aying.............................................. 325
Overview............................................... 325
Contacts Calling up.............................................. 304
Deleting................................................. 305
Downloading (from mobile phone)........ 303 Importing.............................................. 304
Importing (o
verview)............................. 304
Information........................................... .303
Making a call......................................... 305
Na me form at......................................... 304
Options................................................ .305
St oring..................................................3 05
Controller Operating.............................................. 24 9
Con venience closing ................................... 90
Con venience opening ..................................90
Coolant (engine) Check le vel............................................ 361
No tes..................................................... 424
Cooling see Climate control
Co pyright..................................................... 36
Cornering light ...........................................1 22
Cross Traf fic Alert..................................... .218
Crosswind Assist Function/no tes...................................... 171 Index
507

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

see PRE-SAFE
®
PLUS (anticipatory
occupant pr otection plus)
see Restra int sy stem
see Seat belt
Oil see Engine oil
On-board computer Displaying the service due dat e............. 354
Head-up displ aymenu........................... 231
Multifunction display............................. 229
Operating.............................................. 228
Overview of menus................................ 228
On-board diagno stics inter face
see Diagno stics connection
On-boa rdelectronics
Engine electronics................................. 412
No tes..................................................... 412
Tw o-w ayradios...................................... 412
Online services Data storage............................................ 35
Open-source software................................ 36
Operating fluids AdBlue ®
................................................. 421 Ad
ditives (fuel)....................................... 419
Brake fluid............................................. 424
Coolant (engine).................................... 424
Engine oil............................................. .422
Fu el (diesel)...........................................4 19
Fu el (petrol)...........................................4 18
No tes..................................................... 416
Wi ndsc reen washer fluid...................... .425
Operating saf ety
48 V on-boa rdelectrical sy stem.............. 23
Declaration of confo rmity (elect ro‐
magnetic compatibility)........................... 25
Declaration of conformity (jack).............. 28
Declaration of conformity (TIREFIT kit).... 29
Declaration of conformity (wire less
ve hicle components)...............................25
EQ Boo sttech nology............................... 23
Information.............................................. 23
Ope rating sy stem
see On-board computer
Optimised acceleration Activating............................................... 141
Outside mir rors
Anti-dazzle mode (automatic)................ 131Au
tomatic mir rorfo lding function......... .132
Fo lding in/out....................................... 13 0
Operating the memory function............. 11 0
Pa rking position..................................... 131
Setting................................................... 13 0
Overhead control panel Overview.................................................14
Owner's Manual Vehicle equipment................................... 23
Owner's Manual (digital)............................ 20 P
Pa int code .................................................. .414
Pa intwork (cleaning instructions) ...........364
Park position
Inserting................................................ 15 2
Selecting au tomatical ly......................... 15 2
Park ing
see Electric parking brake
Park ing aid
see Parking Assist PARKTRONIC
Park ing Assist PARKTRONIC
Ac tivating............................................... 213524
Index