2018 MERCEDES-BENZ C-CLASS CABRIOLET coolant level

Coolingwit h air dehumidif ication
(multimedia system) ...................... 258
Defrosting the windows ................ .119
Defrosting the windshield .............. 118
ECO start/stop function ................ 116
General notes ................................ 115
Indicator lamp ................................ 117
Ionization ....................................... 120
Ionization (multimedia system) ...... 258
Notes on using the automatic cli-
mate control .................................. 116
Overview ........................................ 257
Overview of systems ......................1 15
Problem with the rear window
defroster ........................................ 119
Problems with cooling with air
dehumidification ............................ 117
Refrigerant ..................................... 344
Refrigerant filling capacity ............. 345
Setting the air distribution ............. 118
Setting the air vents ......................1 20
Setting the airflow ......................... 118
Setting the climate mode (multi-
media system) ............................... 258
Setting the temperature ................ 118
Switching air-recirculation mode
on/off ............................................ 120
Switching on/off ........................... 116
Switching the rear window
defroster on/off ............................ 119
Switching the synchronization
function on and off ........................ 118
Synchronization function (multi-
media system) ............................... 258
Climate control settings
Multimedia system ........................ 257
Climate control system
Climate control .............................. 116
Cockpit
Overview .......................................... 35
Code for Apps
see QR code
COMAND display
Cleaning ......................................... 293
Combination switch .......................... 108
Connecting a USB device
see also Digital Operator's Man-
ual ..................................................2
53C
onsumption statistics (on-board
computer) .......................................... 197
Controller ...........................................2 54
Controlling the speed
see Distance Pilot DISTRONIC
Convenience opening feature ............ 90
Coolant (engine)
Checking the level ......................... 284
Display message ............................ 225
Filling capacity ............................... 344
Important safety notes .................. 343
Temperature display in the instru-
ment cluster .................................. 193
Warning lamp ................................. 248
Cooling
see Climate control
Copyright ............................................. 34
Cornering light function
Display message ............................ 224
Function/notes .............................1 09
Crosswind Assist ................................. 71
Cruise control
Cruise control lever ....................... 152
Deactivating ................................... 153
Display message ............................ 232
Driving system ............................... 151
Function/notes .............................1 51
General notes ................................ 151
Important safety notes .................. 151
Setting a speed .............................. 152
Storing and maintaining current
speed ............................................. 152
Storing the current speed or call-
ing up the last stored speed .......... 152
Cup holder
Center console .............................. 268
Important safety notes .................. 267
Rear compartment ......................... 268
Customer Assistance Center
(CAC) ..................................................... 31
Customer Relations Department ....... 31
D
Dashboard
see Instrument cluster
Dashboard lighting
see Instrument cluster lighting
8Index

Vehicle batterysee Battery (vehicle)
Vehicle dimensions ........................... 345
Vehicle emergency locking ................ 83
Vehicle identification number
see VIN
Vehicle identification plate .............. 339
Vehicle level
AIRMATIC ...................................... 164
Display message ............................ 228
Video
Operating the DVD ......................... 201
see also Digital Operator's Man-
ual .................................................. 253
VIN
Seat ............................................... 340
Type plate ...................................... 339
W
Warning and indicator lampsABS ................................................ 244
Active Brake Assist ........................ 250
Airbag ............................................ 247
Brakes ........................................... 243
Coolant .......................................... 248
Distance warning ........................... 250
Engine diagnostics ......................... 247
ESP
®.............................................. 244
ESP®OFF ....................................... 246
Fuel tank ........................................ 247
General notes ................................ 241
Overview .......................................... 36
Parking brake ................................ 247
PASSENGER AIR BAG ...................... 44
Reserve fuel ................................... 247
Restraint system ............................ 247
Seat belt ........................................ 241
SPORT handling mode ................... 246
Steering ......................................... 252
Tire pressure monitor .................... 251
Warranty .............................................. 28
Washer fluid
Display message ............................ 239
Weather display (COMAND)
see also Digital Operator's Man-
ual .................................................. 253 Wheel and tire combinations
Tires ............................................... 336
Wheel bolt tightening torque ........... 336
Wheel chock ...................................... 332
Wheels
Changing a wheel .......................... 331
Checking ........................................ 313
Cleaning ......................................... 291
Important safety notes .................. 312
Information on driving .................... 312
Interchanging/changing ................ 331
Mounting a new wheel ................... 335
Mounting a wheel .......................... 332
Removing a wheel .......................... 335
Snow chains .................................. 315
Storing ........................................... 332
Tightening torque ........................... 336
Wheel size/tire size ....................... 336
Wind deflector (cleaning instruc-
tions) .................................................. 289
Wind screen ......................................... 91
Wind screen (cleaning instruc-
tions) .................................................. 290
Windows
see Side windows
Windshield
Defrosting ...................................... 118
Windshield washer fluid
see Windshield washer system
Windshield washer system
Adding washer fluid ....................... 285
Important safety notes .................. 344
Windshield wipers
Problem (malfunction) ................... 114
Repl acing the w
iper blades ............ 112
Switching on/off ........................... 111
Winter driving
Important safety notes .................. 314
Slippery road surfaces ................... 151
Snow chains .................................. 315
Winter operation
Radiator cover ............................... 282
Summer tires ................................. 314
Winter tires
M+S tires ....................................... 314
Wiper arm
Moving to a vertical position .......... 112
24Index

ProblemPossible causes/consequences andMSolutions
The engine does not
start. The starter motor
can be heard. The
reserve fuel warning
lamp is lit and the fuel
gauge display is at the
reserve level.The fuel tank is empty.
XRefuel the vehicle.
The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the battery is too weak or
discharged.
XJump-start the vehicle (Ypage 304).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop.
The starter motor was exposed to a thermal load that was too high.
XTry to start the engine again (Ypage 125).
If the engine still does not start:
XConsult a qualified specialist workshop.
The engine is not running
smoothly and is misfir-
ing.There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
XOnly depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it.
XHave the cause rectified immediately at a qualified specialist work-
shop.
The coolant temperature
display is pointing to the
red mark.The coolant level is too low. The coolant is too hot and the engine is no
longer being cooled sufficiently.
XStop as soon as possible and allow the engine and the coolant to
cool down.
XCheck the coolant level (Ypage 284). Observe the warning notes
as you do so and add coolant if necessary.
DYNAMIC SELECT switch
Mercedes-AMG vehicles
General information
Use the DYNAMIC SELECT switch to select the
drive program. Available drive programs for Mercedes-
AMG C 43 4MATIC:
S+
Sport PlusParticularly sporty driving
characteristics
SSportSporty driving characteris-
tics
C ComfortComfortable and economi-
cal driving characteristics
EEconomyParticularly economical
driving characteristics
IIndividualIndividual settings
130DYNAMIC SELECT switch
Driving and parking

Tachometer
!
Do not drive in the overrevving range, as this
could damage the engine.
The red band in the tachometer indicates the
engine's overrevving range.
The fuel supply is interrupted to protect the
engine when the red band is reached.
Outside temperature display
You should pay special attention to road condi-
tions when temperatures are around freezing
point.
Bear in mind that the outside temperature dis-
play indicates the temperature measured and
does not record the road temperature.
The outside temperature display is in the multi-
function display (
Ypage 194).
Changes in the outside temperature are dis-
played after a short delay.
Coolant temperature gauge
GWARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
!If the coolant temperature is too high, a dis-
play message is shown.
If the coolant temperature display is in the
area marked in red, do not continue driving.
Otherwise, the engine will be damaged.
The coolant temperature gauge is in the lower
section of the tachometer (
Ypage 36).
Under normal operating conditions and at the
correct coolant level, the display may rise to the
red mark.
Operating the on-board computer
:Multifunction display
;Right control panel
=Left control panel
XTo activate the on-board computer: switch
on the power supply.
You can control the multifunction display and
the settings in the on-board computer using the
buttons on the multifunction steering wheel.
Left control panel
òROpens a menu list
9
:Press briefly:
RScrolls in lists
RSelects a menu or function
RIn the RadioorMediamenu:
opens a track or station list and
selects a station, an audio track or
a video scene.
RIn the Telephonemenu: switches
to the phone book and selects a
name or a telephone number
9
:Press and hold:
RScrolls quickly through all lists
RIn the RadioorMediamenu:
selects a station, audio track or
video scene using rapid scrolling
RIn the Telephonemenu: starts
rapid scrolling if the phone book is
open
Displays an doperation193
On-boa rd computer and displays
Z

Engine
Display messagesPossible causes/consequences andMSolutions
+
CheckCoolantLevelSee Operator's Man‐ual
The coolant level is too low.
!Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
XAdd coolant, observing the warning notes before doing so
(Ypage 284).
If you have to add coolant frequently:
XContact a qualified specialist workshop and have the engine cooling
system checked.
?The fan motor is malfunctioning.
XIf the coolant temperature is below the red marking in the coolant
temperature gauge, drive to the nearest qualified specialist work-
shop.
XAvoid heavy loads on the engine as you do so, e.g. driving in moun-
tainous terrain and stop-and-go traffic.
?
Coolant Too HotStop Vehicle TurnEngine Off
The coolant is too hot.
A warning tone also sounds.
GWARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to catch
fire.
Steam from the overheated engine can also cause serious burns which
can occur just by opening the hood.
There is a risk of injury.
XPull over and stop the vehicle safely and switch off the engine, pay- ing attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 143).
XWait until the engine has cooled down.
XMake sure that the air supply to the engine radiator is not blocked,
e.g. by snow, slush or ice.
XDo not start the engine again until the display message goes out and
the coolant temperature gauge is below the red marking. Other-
wise, the engine could be damaged.
XPay attention to the coolant temperature gauge.
If the temperature increases again:
XVisit a qualified specialist workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature gauge may rise to the red marking.
Display messages225
On-board computer and displays
Z

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
?NThe red coolant warning lamp comes on while the engine is running.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may be blocked or
the electric engine radiator fan may be defective.
The coolant is too hot and the engine is no longer being cooled sufficiently.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 143).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 284).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
XDo not start the engine again until the coolant temperature gauge is below the
red marking. Otherwise, the engine could be damaged.
XDrive to the nearest qualified specialist workshop.
XAvoid heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-and-go traffic.
?N The red coolant warning lamp comes on while the engine is running. A warning
tone also sounds.
The coolant temperature gauge has reached the red marking. The airflow to the
engine radiator may be blocked or the coolant level may be too low.
GWARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive when your engine is overheated. This can cause some fluids which
may have leaked into the engine compartment to catch fire.
Steam from the overheated engine can also cause serious burns which can occur
just by opening the hood.
There is a risk of injury.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 143).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 284).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
Warning and indicator lamps in the instrument cluster249
On-board computer and displays
Z

Additional service products
Import ant safety notes
GWARNIN G
Certain component sin th eengin ecompart-
ment, suc has th eengine, radiato rand part s
of th eexhaust system, can become ver yhot .
Working in th eengin ecompartmen tposes a
ris kof injury.
Wher epossible, let th eengin ecool down and
touch only th ecomponent sdescribed in th e
following.
GWARNIN G
The engin ecompartmen tcontain smoving
components. Certain components, suc has
th eradiato rfan ,may continu eto run or start
again suddenly when th eignition is off .There
is aris kof injury.
If you need to do any wor kinside th eengin e
compartment:
Rswitch off th eignition
Rnever reac hint oth earea wher ethere is a
ris kof danger from moving components,
suc has th efan rotation area
Rremove jewelr yand watches
Rkeep items of clothing and hair ,for exam-
ple, away from moving part s
GWARNING
The coolin gsystem is pressurized, particularly
when th emotor is warm .If you open th ecap ,
you could be scalded if hot coolan tsprays out .
There is aris kof injury.
Let th eengin ecool down before you open th e
cap .Wear gloves and eye protection .Slowly
open th ecap to reliev epressure.
GWARNIN G
Opening th ehoo dwhen th eengin eis over-
heated or when there is afir ein th eengin e
compartmen tcould expos eyou to hot gase s
or other servic eproducts .There is aris kof
injury.
Let an overheate dengin ecool down before
opening th ehood. If there is afir ein th e
engin ecompartment, keep th ehoo dclosed
and contact th efir edepartment.
Checking coolant level
Checking th ecoolan tlevel (example)
XPark th evehicl eon alevel surface.
Only chec kth ecoolan tlevel when th evehicl e
is on alevel surfac eand th eengin ehas cooled
down .
XTurn th eSmartKey to position 2in th eigni-
tion loc k (Ypage 123).
or
XPress th eStart/Sto pbutto ntwice on vehicles
wit hKEYLESS-GO or th eKEYLESS-GO start
function (
Ypage 124).
XCheckth ecoolan ttemperature display in th e
instrumen tcluste r (Ypage 36).
The coolan ttemperature mus tbe belo w
15 8 ‡ (70 †).
XTurn th eSmartKey to position gin th eigni-
tion loc k (Ypage 123).
or
XPress th eStart/Sto pbutto nonce on vehicles
wit hKEYLESS-GO or th eKEYLESS-GO start
function (
Ypage 124).
XSlowly tur ncap :half atur ncounter-clock -
wise and allow excess pressur eto escape.
XTurn cap :further counter-clockwise and
remove it .
If th ecoolan tis at th elevel of marke rbar =
in th efiller neck when cold, there is enough
coolan tin coolan texpansion tan k;.
If th ecoolan tlevel is approximately 0. 6in
(1. 5cm) abov emarke rbar =in th efiller neck
when warm ,there is enough coolan tin expan -
sion tan k;.
284Engine compartment
Maintenance and care

XIf necessary, add coolant that has been tested
and approved by Mercedes-Benz.
XReplace cap:and turn it clockwise as far as
it will go.
For further information on coolant, see
(
Ypage 343).
Adding washer fluid to the windshield
washer system
GWARNING
Windshield washer concentrate could ignite if it comes into contact with hot engine compo-
nents or the exhaust system. There is a risk of
fire and injury.
Make sure that no windshield washer con-
centrate is spilled next to the filler neck.
Example: adding liquid to the windshield
washer system
XTo open: pull cap:upwards by the tab and
open.
XAdd the premixed washer fluid.
XTo close: press cap :onto the filler neck
until it engages.
If the washer fluid level drops below the recom-
mended minimum fluid level of 1.1 US qt (1.0 l),
a message appears in the multifunction display
prompting you to add washer fluid (
Ypage 239).
Further information on washer fluid
(
Ypage 344).
ASSYST PLUS
Service message
The ASSYST PLUS service interval display
informs you of the next service due date. Information on the type of service and service
intervals (see the separate Maintenance Book-
let).
Further information can be obtained at a quali-
fied specialist workshop, e.g. an authorized
Mercedes-Benz Center, or at
http://www.mbusa.com (USA only).
iThe ASSYST PLUS service interval display
does not show any information on the engine
oil level. Observe the notes on the engine oil
level (
Ypage 282).
The multifunction display shows a service mes-
sage for several seconds, e.g.:
RService A in XX Days
RService A Due
RService A Overdue by XX Days
Depending on the operating conditions of the
vehicle, the remaining time or distance until the
next service due date is displayed.
The letter A
orB, possibly in connection with a
number or another letter, indicates the type of
service. A
stands for a minor service and Bfor a
major service.
You can obtain further information from an
authorized Mercedes-Benz Center.
The ASSYST PLUS service interval display does
not take into account any periods of time during
which the battery is disconnected.
Maintaining the time-dependent service sched-
ule:
XNote down the service due date displayed in
the multifunction display before disconnect-
ing the battery.
or
XAfter reconnecting the battery, subtract the
battery disconnection periods from the ser-
vice date shown on the display.
Hiding a service message
XPress the aor% button on the steering
wheel.
Displaying service messages
XSwitch on the ignition.
XUse ò on the steering wheel to call up the
list of menus.
ASSYST PLUS285
Maintenance and care
Z