2021 MERCEDES-BENZ C-CLASS CABRIOLET engine

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

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
8 Fu elreser ve wa rning lamp
lights up *T
he yellow fuel reser vewarning lamp lights up while the engine is running.
The fuel supply has dropped into there ser verange. #
Refuel. Brakes
Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
! Elect ric pa rking brake indi‐
cator lamp (red)
!
The elect ric pa rking brake
(yellow) indicator lamp *T
he red elect ric pa rking brake indicator lamp flashes or is lit.
The yellow elect ric pa rking brake indicator lamp also lights up in theev ent of a malfunction. #
Notethe messages on the multifunction displa y.492
Display messages and warning/indicator lamps

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
J Brake sy stem warning lamp
(yellow) *T
he yellow brake sy stem warning lamp is lit while the engine is running. &
WARNING Risk of an accident due toa brake sy stem malfunction
If th e brake sy stem is malfunctioning, braking characteristics may be impaired. #
Drive on carefull y. #
Have the brake sy stem checked immediately at a qualified specialist workshop. #
Adjust your speed and drive on carefull y,leaving a suitable dis tance totheve hicle in front. #
Ifth e multifunction display sho wsa display message, obse rve it. #
Consult a qualified specialist workshop.
J Brake sy stem warning lamp
(red) *T
he red brake sy stem warning lamp is lit while the engine is running.
Po ssible causes:
R The brake forc e boosting is malfunctioning and the braking characteristics may be af fected.
R The reis insuf ficient brake fluid in the brake fluid reser voir. #
Notethe messages on the multifunction displa y. &
WARNING Risk of accident and inju ryif brake forc e boosting is malfunctioning
If brake forc e boosting is malfunctioning, increased brake pedal forc e may be necessary for braking. The braking
ch aracteristics may be impaired. The braking dis tance can increase in emergency braking situations. Display messa
ges and warning/indicator lamps 493

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
Fu nction of Active Brake Assi st (/ page 189).
ä Suspension warning lamp
(yellow) *T
he yellow AIRMATIC warning lamp is lit.
The yellow DYNA MIC BODY CONTROL warning lamp is lit.
A fault has occur red in AIRMATIC.
A fault has occur red in theDY NA MIC BODY CONTROL. #
Notethe messages on the multifunction displa y.Driving saf
ety sy stems Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
! ABS warning lamp *T
he yellow ABS warning lamp is lit while the engine is running.
ABS is malfunctioning.
If an additional warning tone sounds, EBD is malfunctioning.
Other driving sy stems and driving saf ety sy stems may also be malfunctioning. #
Notethe messages on the multifunction displa y. &
WARNING Thereis a risk of skidding if EBD or ABS is malfunctioning
The wheels may lock during braking. Display messages and
warning/indicator lamps 495

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
The steerability and braking characteristics are heavily impaired and the braking dis tance may increase. In addi‐
tion, other driving saf ety sy stems are switched off. #
Drive on carefull y. #
Have the brake sy stem checked immediately at a qualified specialist workshop. ÷
ESP ®
wa rning lamp *
The yellow ESP ®
wa rning lamp flashes while theve hicle is in motion.
or
The yellow ESP ®
wa rning lamp is lit while the engine is running.
The yellow ESP ®
wa rning lamp flashes while theve hicle is in motion:
One or more wheels has reached its grip limit (/ page170). #
Adapt your driving style to suit thero ad and weather conditions.
The yellow ESP warning lamp ®
is lit while the engine is running.
ESP ®
is malfunctioning.
Other driving sy stems and driving saf ety sy stems (e.g. BAS) may also be malfunctioning. #
Notethe messages on the multifunction displa y. &
WARNING Risk of skidding if ESP ®
is malfunctioning
If ESP ®
is malfunctioning, ESP ®
cannot car ryout vehicle stabilisation. In addition, other driving saf ety sy stems
are switched off. 496
Display messages and warning/indicator lamps

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions #
Drive on carefull y. #
Have ESP ®
ch ecked at a qualified specialist workshop. å
ESP ®
OFF warning lamp *
The yellow ESP ®
OFF warning lamp is lit while the engine is running.
ESP ®
is deacti vated.
Other driving sy stems and driving saf ety sy stems may also be inoperative. &
WARNING Risk of skidding when driving wi thESP ®
deacti vated
ESP ®
does not act tostabilise theve hicle. The availability of fur ther driving saf ety sy stems is also limited. #
Drive on carefull y. #
Deactivate ESP ®
only for as long as the situation requ ires.
If ESP ®
cannot be activated, ESP ®
is malfunctioning. #
Have ESP ®
ch ecked immediately at a qualified specialist workshop. #
Obser vethe no tes on deactivating ESP ®
(/ page 170). Displ
aymessa ges and warning/indicator lamps 497

Sy
stem limits.........................................1 98
Tr ailer operation.................................... 19 8
Ac tive Parking Assist
Exiting a parking space......................... .216
Fu nction................................................. 213
Pa rking................................................. .215
Sy stem limitations................................. 213
Ac tive Se rvice Sy stem PLUS
see AS SYST PLUS
Ac tive Speed Limit Assi st
Displ ay.................................................. 183
Fu nction................................................ 183
Ac tive Steering Assist
Ac tivating/deactivating......................... 187
Ac tive Emergency Stop Assis t............... 188
Fu nction................................................ 186
Sy stem limits.........................................1 86
Ad aptive brake lights ................................ 174
Ad aptive cruise control
see Active Dis tance Assi stDISTRONIC
Ad aptive Highbeam Assist Plus
Fu nction................................................. 124
Switching on/of f................................... 12 5Ad
Blue ®
Ad ditives................................................ 421
Capacity................................................ 422
No tes..................................................... 15 8
Purity..................................................... 421
To pping up............................................. 15 9
Ad ditional door lo ck.................................... 75
Ad diti ves
Ad Blue ®
................................................. 421
Engine oil.............................................. 422
Fu el........................................................4 19
Ad diti ves (AdBlue ®
)
see AdBlue ®
Ad diti ves (engine oil)
see Additives
Ad diti ves (fuel)
see Fuel
Ad dress book
see Contacts
Ad justing bass, mid- range and treble
settings
Adva nced sound sy stem........................3 53Ad
justing mid- range, treble and bass
settings
Adva nced sound sy stem........................3 53
Ad justing the balance/ fader
Adva nced sound sy stem........................3 53
Burmes ter®
sur round sound sy stem..... 353
Ad justing the bass, mid- range and
treble
Burmes ter®
sur round sound sy stem..... 352
Ad justing the mid- range, treble and
bass
Burmes ter®
sur round sound sy stem..... 352
Ad justing the sound focus
Burmes ter®
sur round sound sy stem..... 353
Ad justing treble, mid- range and bass
settings
Adva nced sound sy stem........................3 53
Burmes ter®
sur round sound sy stem..... 352
ADS PLUS damping sy stem
see AIRMATIC
Ad vanced sound sy stem
Ad justing the balance/fader................. 353 Index
501