2015 MERCEDES-BENZ C-CLASS COUPE warning

Display messages
Possible causes/consequences and
M
MSolutions !
Parkin
gbrake inop‐
Parkin gbrake inop‐
erative erative The yellow
!warning lamp lights up. The red !indicator lamp
flashes for about te nseconds after th eelectric parking brak ehas been
applie dorreleased. It then goe sout or remain slit.
The electric parking brak eismalfunctioning ,e.g.b ecause of over-
voltag eorundervoltage.
X Rectify th ecaus eoft heovervoltage or undervoltage, e.g. by charg-
ing th ebattery or restarting th eengine.
X Apply or release th eelectric parking brake.
If th eelectric parking brak estill canno tbeappliedorr eleased:
X Switc hoff th eignition and tur nitbacko n.
X Apply or release th eelectric parking brake.
If th eelectric parking brak estill canno tbereleased:
X Consult aqualified specialist workshop.
If it is still no tpossibl etoapply th eelectric parking brake:
X Consult aqualified specialist workshop. The yellow
!warning lamp lights up and th ered ! indicator
lamp flashes.
It is no tpossibl etoapply th eelectric parking brak emanually.
X Vehicles wit hmanua ltra nsmission: engage first gear.
X Vehicles wit hautomatic transmission: shift thetransmission to
position P.
X Consult aqualified specialist workshop. J
Check brake fluid Check brake fluid
level level There is insufficien
tbrak efluid in th ebrak efluid reservoir.
In addition ,the red J warning lamp lights up in th einstrument
cluste rand aw arning tone sounds.
G WARNING
Braking efficiency may be impaired.
There is ariskofana ccident.
X Pull ove rand stop th evehicl esafely as soo naspossible, paying
attention to roa dand traffic conditions. Do no tcontinue driving
under any circumstances.
X Safeguar dthe vehicl eagainst rollin gaway (Y page 172).
X Consult aqualified specialist workshop.
X Do no ttop up th ebrak efluid .This does no tcorrect thef ault. #
Check Check
brake
brakepad
padwear
wear The brak
epads/linings hav ereached their wear limit.
X Consult aqualified specialist workshop. G
Inoperative Inoperative On
eorm orem ain features of th eMercedes-Ben zContac tsystem are
malfunctioning.
X Consult aqualified specialist workshop. Display
messages
259On-boardcomputer an ddisplays Z

Display messages
Possible causes/consequences and
M
MSolutions PRE-SAFE Functions
PRE-SAFE Functions
limited limited
See
SeeOwner's
Owner's
Manual
Manual PRE
‑SAFE ®
PLU SorP RE‑SAFE ®
Brake is unavailable due to amal-
function .BAS PLU SwithC ross-Traffic Assis tmay also hav efailed.
X Consult aqualified specialist workshop immediately. Radar
Radar
sensors
sensors dirty
dirty
See Owner' sManual
See Owner' sManual At least on
eofthefollowin gdrivin gsystems or drivin gsafet ysystems
is temporarily restricted or inoperative:
R PRE-SAFE ®
PLUS
R PRE-SAFE ®
Brake
R COLLISION PREVENTION ASSIST PLUS
R Active Lan eKeepin gAssist
R Active Blind Spot Assist
R DISTRONI CPLUSw ithS teering Assis tand Stop&Go Pilot
If th eradar sensor system in fron tisdirty, Active Blind Spot Assis twill
no tp erfor mac ourse-correcting brak eapplication.
Possibl ecauses:
R thes ensor sintheradiato rtrima nd/o rinthebumpers are dirty
R thef unction of th edrivin gsystem or drivin gsafet ysystem is
impaire ddue to heav yrain or snow
Aw arning tone also sounds.
Once th ecauses listed abov enolonger apply, th edisplay message
goe sout.A lldrivin gsystems or drivin gsafet ysystems are operative
again.
If th edisplay message does no tdisappear:
X Pull ove rand stop th evehicl esafely as soo naspossible, paying
attention to roa dand traffic conditions.
X Safeguar dthe vehicl eagainst rollin gaway (Y page 172).
X Switc hoff th eengine.
X Clean th esensor s(Ypage 330) in th efollowin glocations:
R in th eradiato rtrim
R in th efront bumper
R in th erear bumper, particularly in th emiddle of th erear bumper
X Restart th eengine.
The display message disappears. 6
Restraint sys
.mal‐
Restraint sys .mal‐
function Consult function Consult
workshop workshop The restrain
tsystem is faulty. The 6warning lamp also lights up in
th ei nstrumen tcluster.
G WARNING
The airbags or belt tensioners may either be triggered unintentionally or, in th eevent of an accident, may no tbetriggered.
This poses an increased ris kofinjury.
X Consult aqualified specialist workshop immediately.
Fo rfurther information about th erestrain tsystem, see (Y page 39). Display
messages
261On-boardcomputer an ddisplays Z

Display messages
Possible causes/consequences and
M
MSolutions 6
Front lef
tmalfunc‐
Front lef tmalfunc‐
tio nC onsul twork‐
tio nC onsul twork‐
shop shop orFront right
Front right
malfunction
malfunction Consult
Consult
workshop
workshop The restrain
tsystem has malfunctioned at th efront on th eleftorr ight.
The 6 warning lamp also lights up in th einstrumen tcluster.
G WARNING
The airbags or belt tensioners may either be triggered unintentionally or, in th eevent of an accident, may no tbetriggered.
This poses an increased ris kofinjury.
X Consult aqualified specialist workshop immediately. 6
Rea
rl eftm alfunc‐
Rea rl eftm alfunc‐
tio nC onsul twork‐
tio nC onsul twork‐
shop shop orRea rr ight
Rea rr ight
malfunction
malfunction Consult
Consult
workshop
workshop The rear left-han
dorright-hand restrain tsystem has malfunctioned.
The 6 warning lamp also lights up in th einstrumen tcluster.
G WARNING
The airbags or belt tensioners may either be triggered unintentionally or, in th eevent of an accident, may no tbetriggered.
This poses an increased ris kofinjury.
X Consult aqualified specialist workshop immediately. 6
Lef
tw indowbag mal‐
Lef tw indowbag mal‐
function Consult function Consult
workshop workshop orRight
Right
windowbag malfunc‐
windowbag malfunc‐
tio nC onsul twork‐
tio nC onsul twork‐
shop shop The lef
torright windowbag is malfunctioning.
The 6 warning lamp also lights up in th einstrumen tcluster.
G WARNING
The lef torright windowbag may either be triggered unintentionally or,
in th eevent of an accident, may no tbetriggered.
This poses an increased ris kofinjury.
X Consult aqualified specialist workshop immediately. 262
Display
messagesOn-boardcomputer an ddisplays

Display messages
Possible causes/consequences and
M
MSolutions Front-passenger
Front-passenger
airbag airbag
disabled
disabled See
See
Owner' sManual
Owner' sManual The front-passenger fron
tairbag and front-passenger kneebag are
disabled during th ejou rney, although:
R an adult
or
R ap erson of th ecorre spondin gstatur eisont hefront-passenger seat
If additional force sare applie dtotheseat ,the weigh tthe system
detects may be to olow.
G WARNING
The front-passenger fron tairbag does no tdeploy during an accident.
This poses an increased ris kofinjury.
X Pull ove rand stop th evehicl esafely as soo naspossible, paying
attention to roa dand traffic conditions.
X Safeguar dthe vehicl eagainst rollin gaway (Y page 172).
X Switc hthe ignition off.
X Hav ethe occupant on th efront-pa ssenger seat step out of the
vehicle.
X Mak esuret hatthe seat is unoccupied ,close th efront-pa ssenger
door and switch on th eignition.
X Observ ethe PASSENGER AI RBAG indicator lamp sinthecentre
console and th emultifunction display and chec kthe following:
Seat unoccupied and ignition switched on:
R as elf-diagnosis is carrie dout.T he PASSENGER AI RBAG OFFa nd
PASSENGER AI RBAG ON indicator lamp smustligh tups imulta-
neousl yfor approximately six seconds
R theP ASSENG ER AIRBAG OFFindicator lamp mus tthe nligh tup
and remain lit after th eself-diagnosis .Iftheindicator lamp is on,
th ea utomatic front-passenger fron tairbag deactivation system
has disabled th efront-pa ssenger fron tairbag (Y page 48)
R the Front-passenger
Front-passenger airbag airbagenabled
enabled See
SeeOwner's
Owner's Manual
Manual
or Front-passenger
Front-passenger airbag
airbagdisabled
disabled See
SeeOwner's
Owner's Manual
Manual
display message smustn otappear in th emultifunction display
X Wait for aperiod of at least 60 seconds until th eneces sarysystem
checks hav ebeen completed.
X Mak esuret hatthe display message sdonotappear in th emulti-
function display.
If these condition sare met ,the front-passenger seat can be occupied
again .Whether th ePASSENG ER AIRBAG OFForONi ndicator lamp
remain slit or goe sout depend sonhow theautomatic front-passenger
fron tairbag deactivation system classifies th eoccupant.
If th econditi onsa re no tmet,t he system is no toperating correctly.
X Consult aqualified specialist workshop immediately.
Further information on th eautomatic front-passenger fron tairbag
deactivation feature (Y page 47). Display
messages
263On-boardcomputer an ddisplays Z

Display messages
Possible causes/consequences and
M
MSolutions Front-passenger
Front-passenger
airbag enable
dSee
airbag enable dSee
Owner' sManual
Owner' sManual The front-passenger fron
tairbag and front-passenger kneebag are
enabled during th ejou rney, although:
R ac hild, asmall adult or an objec tweighing less than th esystem
weigh tthreshold is locate donthefront-passenger seat
or
R thef ront-pa ssenger seat is no toccupied
The system may detec tobjects or force stha tare addin gtotheweight
applie dtotheseat.
G WARNING
The airbag may deploy unintentionally.
This poses an increased ris kofinjury.
X Pull ove rand stop th evehicl esafely as soo naspossible, paying
attention to roa dand traffic conditions.
X Safeguar dthe vehicl eagainst rollin gaway (Y page 172).
X Switc hthe ignition off.
X Ope nthe front-passenger door.
X Remove th echild and th echild restrain tsystem from th efront-
passenger seat.
X Mak esuret he re are no objects applyin gadditional force to th eseat.
The system may otherwise detec tthe additional force and interpret
th es eat occupant's weigh tasgreatertha nita ctually is.
X Mak esuret hatthe seat is unoccupied ,close th efront-pa ssenger
door and switch on th eignition.
X Observ ethe PASSENGER AI RBAG indicator lamp sinthecentre
console and th emultifunction display and chec kthe following:
Seat unoccupied and ignition switched on:
R as elf-diagnosis is carrie dout.T he PASSENGER AI RBAG OFFa nd
PASSENGER AI RBAG ON indicator lamp smustligh tups imulta-
neousl yfor approximately six seconds
R theP ASSENG ER AIRBAG OFFindicator lamp mus tthe nligh tup
and remain lit after th eself-diagnosis .Iftheindicator lamp is on,
th ea utomatic front-passenger fron tairbag deactivation system
has disabled th efront-pa ssenger fron tairbag (Y page 48)
R the Front-passenger
Front-passenger airbag airbagenabled
enabled See
SeeOwner's
Owner's Manual
Manual
or Front-passenger
Front-passenger airbag
airbagdisabled
disabled See
SeeOwner's
Owner's Manual
Manual
display message smustn otappear in th emultifunction display
X Wait for aperiod of at least 60 seconds until th eneces sarysystem
checks hav ebeen completed.
X Mak esuret hatthe display message sdonotappear in th emulti-
function display.
If these condition sare met ,the front-passenger seat can be occupied
again .Whether th ePASSENG ER AIRBAG OFForONi ndicator lamp
remain slit or goe sout depend sonhow theautomatic front-passenger
fron tairbag deactivation system classifies th eoccupant.
If th econditi onsa re no tmet,t he system is no toperating correctly.
X Consult aqualified specialist workshop immediately. 264
Display
messagesOn-boardcomputer an ddisplays

Display messages
Possible causes/consequences and
M
MSolutions Further information on th
eautomatic front-passenger fron tairbag
deactivation feature (Y page 47).Lights
Display messages
Possible causes/consequences and
M
MSolutions b
Lef
td ipped beam
Lef td ipped beam
(Example) The correspondin
gbulb is faulty.
X Consult aqualified specialist workshop.
or X Chec kwhether you are permitte dtoreplace th ebulb yourself
(Y page 123).
i LE
Dl igh tbulbs :the display message for th ecorre spondin glamp
only appear swhen all th eLEDsint helamp hav efailed. b
Active Active
Light
LightSystem
System
inoperative
inoperative The active ligh
tfunction is faulty.
X Consult aqualified specialist workshop. b
Intell
.Light Sys‐
Intell .Light Sys‐
tem inoperative tem inoperative The Intelligent Light Syste
misfaulty. The lighting system continues to
function properly without th efunction softheIntelligent Light System.
X Consult aqualified specialist workshop. b
Malfunction Malfunction
See
SeeOwn‐
Own‐
er' sM anual
er' sM anual The exterio
rlighting is faulty.
X Consult aqualified specialist workshop. Vehicles wit
htrailer to whitch :af usem ay hav eblown.
X Pull ove rand stop th evehicl esafely as soo naspossible, paying
attention to roa dand traffic conditions.
X Safeguar dthe vehicl eagainst rollin gaway (Y page 172).
X Chec kthe fuses (Y page 350).
X If necessary, replace th eblown fuse. Observ ethe warning note sas
you do so.
If th edisplay message continues to be displayed:
X Consult aqualified specialist workshop. b
AUT
Ol ights inoper‐
AUT Ol ights inoper‐
ative ative The ligh
tsensor is faulty.
X Consult aqualified specialist workshop. b
Switch off lights Switch off lights You are leaving th
evehicl eand th elights are switched on .Awarning
tone also sounds.
X Turn th eligh tswitch to the Ãposition. Display
messages
265On-boardcomputer an ddisplays Z

Display messages
Possible causes/consequences and
M
MSolutions b
Switch on headlamps Switch on headlamps You are drivin
gwithout dipped-beam headlamps.
X Turn th eligh tswitch to the Lorà position. Adaptive Highbeam
Adaptive Highbeam
Assist Plu
sinoper‐
Assist Plu sinoper‐
ative ative Adaptive Highbea
mAssistisf aulty.
X Consult aqualified specialist workshop. Adaptive Highbeam
Adaptive Highbeam
Assist Plu
scur‐
Assist Plu scur‐
rently unavailable rently unavailable
See Owner' sManual
See Owner' sManual Adaptive Highbea
mAssistP lus is deactivated and temporarily inop-
erative .Possibl ecauses:
R thew indscree nisdirty in th ecamera' sfield of vision
R visibilit yisimpaire ddue to heav yrain ,sno worf og
X Clean th ewindscreen.
If th esystem detects that th ecamera is full yoperational, the Adap‐
Adap‐
tiv eH ighbeam Assist Plu savailable again
tiv eH ighbeam Assist Plu savailable again display message
is shown.
Adaptive Highbea mAssistP lus is operational again. Engine
Display messages
Possible causes/consequences and
M MSolutions +
Top up coolan
tSee
Top up coolan tSee
Owner’ sManual
Owner’ sManual The coolan
tlevel is to olow.
! Avoid making lon
gjou rneys wit htoo littl ecoolan tint heengine
coolin gsystem. The engin ewill otherwise be damaged.
X Top up th ecoolant, observing th ewarning note sbefore doin gso
( Ypage 324).
If you have to top up th ecoolant frequently:
X Contac taqualified specialist workshop and hav ethe engin ecooling
system checked. ? The fan motor is faulty.
X If th ecoolan ttem perature is belo w120†, you can continu edriving
to th eneares tqualified specialist workshop.
X Avoid heav yloads on th eengineasy ou do so, e.g. drivin ginmoun-
tainous terrain and stop-start traffic. 266
Display
messagesOn-boardcomputer an ddisplays

Display messages
Possible causes/consequences and
M
MSolutions ?
Coolan
tStopv ehi‐
Coolan tStopv ehi‐
cle Switch engine cle Switch engine
off off The coolan
tistoohot.
Aw arning tone also sounds.
G WARNING
Never drive wit hanoverheate dengine. Drivin gwhen your engin eis
overheate dcan caus esom efluid swhichm ay hav eleaked int othe
engin ecom partmen ttocatch fire.
In addition ,steam from an overheate denginec an caus eserious
burns, whic hcan occur jus tbyopening th ebonnet.
There is ariskofi njury.
X Stop th evehicl eimmediately, payin gattention to roa dand traffic
conditions, and switch off th eengine.
X Safeguar dthe vehicl eagainst rollin gaway (Y page 172).
X Wait until th eengineh as cooled down.
X Mak esuret hatthe air supply to th eenginer adiato risnotblocked,
e.g. by frozen slush.
X Do no tstart th eenginea gain until th edisplay message goe sout and
th ec oolan ttem perature is belo w120†. The engin emay otherwise
be damaged.
X Pay attention to th ecoolan ttem perature display.
If th etemperatur eincreases again:
X Consult aqualified specialist workshop immediately.
Under normal operating condition sand wit hthe specified coolant
level, th ecoolan ttem perature may ris eto1 20 †. #
See Owner'
sManual
See Owner' sManual The battery is no
tbein gcharged.
Aw arning tone also sounds.
Possibl ecauses:
R fault yalternator
R torn poly-V-belt
R am alfunction in th eelectronics
! Do no
tcontinue driving. The engin ecould otherwise overheat.
X Stop th evehicl eimmediately, payin gattention to roa dand traffic
conditions, and switch off th eengine.
X Safeguar dthe vehicl eagainst rollin gaway (Y page 172).
X Consult aqualified specialist workshop. Display
messages
267On-boardcomputer an ddisplays Z