2018 MERCEDES-BENZ C-CLASS CABRIOLET warning

Display messagesPossible causes/consequences andMSolutions
Cruise Control- - -mph
RAcondition for activating cruise control has no tbeen met .
You hav etried to store aspeed belo w20 mph (30 km/h), for exam-
ple.
RES P®is deactivated. The yello wES P®OF Fwarning lamp is lit .
XIf conditionspermit ,drive faste rthan 20 mph (30 km/h )and store
th espeed.
or
XChec kth eactivation condition sfor cruise control (Ypage 151).
or
XReactivat eES P®(Ypage 204).
or
XReactivat eES P®in Mercedes-AMG vehicles (Ypage 69).
Cruise Contro lOffCruis econtrol has been deactivated.
If awarning tone also sounds, cruise control has deactivated auto -
matically (
Ypage 151).
Display messages233
On-board computer and displays
Z

Tires
Display messagesPossible causes/consequences andMSolutions
CheckTirePressureSoonCanada only:
The tire pressure loss warning system has detected a significant loss
in pressure.
A warning tone also sounds.
Possible causes:
Ryou have changed the positions of the wheels and tires or installed
new wheels and tires
Rthe tire pressure in one or more tires has dropped significantly
GWARNING
Tire pressures that are too low pose the following hazards:
Rthey may burst, especially as the load and vehicle speed increase.
Rthey may wear excessively and/or unevenly, which may greatly
impair tire traction.
Rthe driving characteristics, as well as steering and braking, may be
greatly impaired.
There is a risk of an accident.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.
XSecure the vehicle against rolling away (Ypage 143).
XCheck the tires and, if necessary, follow the instructions for a flat
tire (Ypage 296).
XCheck the tire pressures and, if necessary, correct the tire pressure.
XRestart the tire pressure loss warning system when the tire pres-
sure is correct (Ypage 319).
CheckTirePressureThen Restart RunFlat Indicator
Canada only:
The tire pressure loss warning system generated a display message
and has not been restarted since.
XSet the correct tire pressure in all four tires.
XRestart the tire pressure loss warning system (Ypage 319).
Run Flat IndicatorInoperativeCanada only:
The tire pressure loss warning system is faulty.
XVisit a qualified specialist workshop.
PleaseCorrectTirePressureThe tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.
XCheck the tire pressures at the next opportunity (Ypage 321).
XIf necessary, correct the tire pressure.
XRestart the tire pressure monitor (Ypage 321).
234Displa y messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
Check TiresThe tire pressurein on eor mor etires has dropped significantly. The
whee lposition is displayed in th emultifunction display.
A warning tone also sounds.
GWARNIN G
Tir epressures that are to olow pos eth efollowin ghazards :
Rthey may burst, especially as th eload and vehicl espeed increase.
Rthey may wear excessivel yand/o runevenly, whic hmay greatl y
impair tire traction .
Rthedrivin gcharacteristics ,as well as steering and braking ,may be
greatl yimpaired.
There is aris kof an accident.
XStop th evehicl ewithout making any sudden steering or braking
maneuvers .Pay attention to th etraffic condition sas you do so.
XSecur eth evehicl eagainst rollin gaway (Ypage 143).
XCheckth etires and ,if necessary, follow th einstruction sfor aflat
tire (Ypage 296).
XChec kth etire pressur e (Ypage 321).
XIf necessary, correc tth etire pressure.
Warnin gTir eMal ‐functionThe tire pressur ein on eor mor etires has dropped suddenly. The whee l
position is shown in th emultifunction display.
GWARNIN G
Drivin gwit h a flat tire poses aris kof th efollowin ghazards :
Raflat tire affects th eabilit yto steer or brak eth evehicl e
Ryou could lose control of th evehicl e
Rcontinued drivin gwit h a flat tire will caus eexcessive heat build-up
and possibl y afire
There is aris kof an accident.
XStop th evehicl ewithout making any sudden steering or braking
maneuvers .Pay attention to th etraffic condition sas you do so.
XSecur eth evehicl eagainst rollin gaway (Ypage 143).
XCheckth etires and ,if necessary, follow th einstruction sfor aflat
tire (Ypage 296).
TirePress.Monito rCurrently Unavaila‐ble
Becausethere is interferenc efrom astron gsource of radi owaves, no
signals from th etire pressur esensor sare detected. The tire pressur e
monitor is temporarily malfunctioning .
XDrive on.
The tire pressur emonitor restarts automatically as soo nas th e
problem has been resolved.
TirePress .Sen ‐sor(s) Missin gThere is no signal from th etire pressur esensor of on eor several tires .
The pressur eof th eaffecte dtire is no tdisplayed in th emultifunction
display.
XHav eth efault ytire pressur esensor replace dat aqualified special -
ist workshop .
Display messages235
On-board computer and displays
Z

Display messagesPossible causes/consequences andMSolutions
Driver's DoorOpe n&Transmission Notin PRis kof Vehi‐cle Rollin gAwa y
The driver's door is open or no tfully closed and th etransmission is in
position k,iorh.
A warning tone also sounds.
GWARNIN G
The vehicl emay rol laway.
There is aris kof an accident.
XShift th etransmission to position j.
XSecureth evehicl eagainst rollin gaway (Ypage 143).
XCloseth edriver's door completely.
Onl yShift to 'P'whe nVehicl eisSta‐tionar y
The vehicl eis moving .
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XShift th etransmission to position j.
ServiceRequiredDoNot Shift GearsVisit Dealer
You canno tchang eth etransmission position due to amalfunction .
A warning tone also sounds.
If transmission position his selected:
XDrive to aqualified specialist workshop without shifting th etrans -
mission from position h.
If transmission position k,iorj is selected:
XSecur eth evehicl eagainst rollin gaway (Ypage 143).
XNotify aqualified specialist workshop or breakdown service.
ReversingNotPossi‐bleServic eRequiredYou canno tshift int otransmission position kdue to amalfunction .
The transmission position sj, iorh continu eto be available.
A warning tone also sounds.
XVisit aqualified specialist workshop .
Transmission Mal‐function StopAmalfunction has occurred in th emechanical transmission compo -
nents.
A warning tone also sounds. The transmission automatically shift sto
position i.
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XShift th etransmission to position j.
XSecureth evehicl eagainst rollin gaway (Ypage 143).
XNotify aqualified specialist workshop or breakdown service.
Display messages23 7
On-board computer and displays
Z

Display messagesPossible causes/consequences andMSolutions
StopVehicl eLeaveEngineRunnin gWaitTransmission Cool‐ing
The transmission has overheated. Pullin gaway can be temporarily
impaire dor no tpossible.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions. Do no tcontinu edrivin g
under any circumstances.
XLeav eth eengin erunning.
XWait until th edisplay message disappear sbefore pullin gaway.
NThe trunk lid is open .
XCloseth etrunk lid.
MThe hoo dis open . Awarning tone also sounds.
GWARNIN G
The open hoo dmay bloc kyour vie wwhen th evehicl eis in motion .
There is aris kof an accident.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 143).
XCloseth ehood.
CAt least on edoor is open . Awarning tone also sounds.
XClos eall th edoors.
_
Front Lef tSea tBackrestNotLockedorFront Right Sea tBackrest Not Locked
The driver's or fron tpassenger's seat backrest is no tengaged. A
warning tone also sounds.
XPush th ebackrest bac kuntil it engages.
Ð
Power Steering Mal ‐function See Opera‐tor's Manual
The powersteering is malfunctioning .
A warning tone also sounds.
GWARNIN G
You will need to use mor eforce to steer .
There is aris kof an accident.
XChec kwhether you are able to apply th eextr aforce required.
If you ar eabl eto steer safely:
XDrive on carefully.
XVisit aqualified specialist workshop immediately.
If you ar eunable to steer safely:
XDo no tdrive on .
XConsult aqualified specialist workshop .
238Display messages
On-board computer and displays

SmartKey
Display messagesPossible causes/consequences andMSolutions
Â
KeyDoesNotBelongto Vehicle
You have put the wrong SmartKey in the ignition lock.
XUse the correct SmartKey.
Â
Take Your Key fromIgnition
The SmartKey is in the ignition lock.
A warning tone sounds
XRemove the SmartKey.
Â
Obtain a New Key
The SmartKey needs to be replaced.
XVisit a qualified specialist workshop.
Â
Replace Key Battery
The SmartKey battery is discharged.
XChange the batteries (Ypage 79).
Â
Don't Forget YourKey
The SmartKey is not in the ignition lock. You have opened the driver's
door with the engine switched off. A warning tone sounds
This display message is displayed for a maximum of 60 seconds and is
simply a reminder.
XTake the SmartKey with you when you leave the vehicle.
Â
Key Not Detected(white display message)
The SmartKey is currently undetected.
XChange the location of the SmartKey in the vehicle.
If the SmartKey still cannot be detected:
XInsert the SmartKey into the ignition lock and turn it to the desired position.
Â
Key Not Detected(red display message)
The SmartKey is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle cen-
trally or start the engine.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 143).
XLocate the SmartKey.
XPress aon the steering wheel to confirm the display message.
240Display messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
Becausethere is interferenc efrom astron gsource of radi owaves, th e
SmartKey is no tdetecte dwhils tth eengin eis running.
A warning tone also sounds.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 143).
XInsertth eSmartKey int oth eignition loc kand drive in SmartKey
mode.
Â
Remove 'Start 'But ‐ton and Insert Key
The SmartKey is continually undetected.
The SmartKey detection function has atemporar ymalfunction or is
faulty. Awarning tone also sounds.
XInser tth eSmartKey int oth eignition loc kand tur nit to th edesire d
position .
XVisitaqualified specialist workshop .
Warning and indicat orlamps in the instrume nt cluster
General notes
Some systems carry out aself-diagnosis when th eignition is switched on .Therefore ,som eindicator
and warning lamp smay ligh tup or flas htemporarily. This behavio ris non-critical .These indicator
and warning lamp sonly indicat e amalfunction if they ligh tup or flas hafter starting th eengin eor
whils tdriving.
Safety
Seat belts
Warning/
indicator
lam pNSignal type
Possible causes/consequences and M
Solutions
üNAfte rstarting th eengine, th ered seat belt warning lamp lights up for six sec -
onds.
The seat belt warning lamp remind sth edriver and fron tpassenger to faste ntheir
seat belts.
XFaste nyour seat belt (Ypage 47).
üNAfte rstarting th eengine, th ered seat belt warning lamp lights up. In addition , a
warning tone sounds for up to six seconds.
The driver's seat belt is no tfastened.
XFaste nyour seat belt (Ypage 47).
The warning tone ceases .
Warning and indicator lamps in the instrument cluster241
On-board computer and displays
Z

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
üNThe red seat belt warning lamp lights up after the engine starts, as soon as the
driver's or the front-passenger door is closed.
The driver or front passenger has not fastened their seat belt.
XFasten your seat belt (Ypage 47).
The warning lamp goes out.
There are objects on the front-passenger seat.
XRemove the objects from the front-passenger seat and stow them in a secure
place.
The warning lamp goes out.
üN The red seat belt warning lamp flashes and an intermittent audible warning
sounds.
The driver or front passenger has not fastened their seat belt. The vehicle is being driven faster than 15 mph (25 km/h) or has briefly been driven faster than 15 mph
(25 km/h).
XFasten your seat belt (Ypage 47).
The warning lamp goes out and the intermittent warning tone ceases.
There are objects on the front-passenger seat. The vehicle is being driven faster
than 15 mph (25 km/h) or has briefly been driven faster than 15 mph (25 km/h).
XRemove the objects from the front-passenger seat and stow them in a secure
place.
The warning lamp goes out and the intermittent warning tone ceases.
242Warning and indicator lamps in the instrument cluster
On-board computer and displays