warning light MERCEDES-BENZ C-CLASS SALOON 2012 Repair Manual

not pe
rmit any reliable conclusion about the tyre
pressure.
Only cor rect tyre pressures when the tyres are
cold. Conditions for cold tyres:
R The vehicle has been par ked with the tyres
out of direct sunlight for at least thre e hours.
R The vehicle has tr avelled less than 1.6 km.
The vehicle's tyres heat up when driving. As the
te mp erature of the tyres increases, so too does
th e tyre pressure.
Ve hicles with a tyre pressure monitoring sys‐
te m: you can also check the tyre pressure using
th e on-board computer.
Note s on trailer operation
Alw ays inflate there ar axle tyres tothere com‐
mended tyre pressures on the tyre pressure
ta ble for increased load. Ty
re pressure table The tyre pressure
table is on the inside of the
fuel filler flap. If one or more tyre sizes precede a tyre pres‐
sure,
thefo llowing tyre pressure information is
only valid forth ose tyre sizes and their respec‐
tive load condition.
If th e preceding tyre sizes are complemented by
th e+ symbol, the tyre pressure information
fo llowing sho wsalternative tyre pressures. Fuel
consum ption may then increase slightl y.The load conditions "partially laden" and "fully
laden" are defined in
theta ble for dif fere nt num‐
be rs of passengers and amounts of luggage. The
actual number of seats may dif fer from this. Ty
re pressure moni toring sy stem Fu
nction of the ty repressure moni toring sys‐
tem
The sy stem checks the tyre pressure and the
tyre temp erature of the tyres fitted totheve hicle
by means of a tyre pressu resensor.
The tyre pressure and the tyre temp erature
appear in the on-board computer (/ page413).
If th ere is a subs tantial pressure loss or if the
tyre temp erature is excessive, you will be
wa rned in thefo llowing ways:
R via display messa ges (/ page 489).
R viatheh warning lamp in the instrument
clus ter (/ page511)
The tyre pressu remonitoring sy stem is only an
aid. It is the driver's responsibility toset the tyre 412
Wheels and tyres
Internal use only

*
NO
TEDama gecaused byincor rect cool‐
ant #
Only use coolant that has been pre‐
mixed with therequ ired antifreeze pro‐
te ction.
Information on coolant is available at thefo l‐
lowing locations:
R inthe Mercedes-Benz Specification for
Operating Fluids 310.1
- at https://be vo.mercedes-benz.com
- inthe Mercedes-Benz BeVo app
R at a qualified specialist workshop *
NO
TEOverheating at high outside tem‐
peratures If an inapp
ropriate coolant is used, the
engine cooling sy stem is not suf ficiently pro‐
te cted against overheating and cor rosion at
high outside temp eratures. #
Alw ays use coolant appr ovedby
Mercedes-Benz. #
Obser vethe instructions in the
Mercedes-Benz Specifications for Oper‐
ating Fluids 310.1. Ha
ve the coolant regularly replaced at a qualified
specialist workshop.
Proportion of antifreeze concentrate in the
engine cooling sy stem:
R a minimum of 50% (antifreeze pr otection
down toappr oximately -37°C)
R a maximum of 55% (antifreeze pr otection
down to-45°C) Note
s on windscreen washer fluid Obser
vethe no tes on operating fluids
(/ page 430). &
WARNING ‑ Risk of fire and injury due to
windscreen washer concentrate
Wi ndsc reen washer concentrate is highly
fl ammable. It could ignite if it comes into
con tact with hot engine component parts or
th eex haust sy stem. #
Make sure that no windscre enwasher
concentrate spills out next tothefiller
opening. *
NO
TEDama getotheex terior lighting
due tounsuitable windsc reen washer
fl uid Uns
uitable windsc reen washer fluids may
damage the plastic sur face of theex terior
lighting. #
Only use windscreen washer fluids
which are also suitable for use on plas‐
tic sur faces, e.g. MB SummerFit or MB
Wi nterFit. *
NO
TEBlocked spr aynozzles caused by
mixing windscreen washer fluids #
Do not mix MB SummerFit and MB Win‐
te rFit with other windscreen washer flu‐
ids. Te
ch nical da ta439
Internal use only

Lights
Display messages
Possible causes/consequences and M
MSolutions
: Left dipped beam (examp le) *T
he cor responding light source is defective. #
Drive on carefully. #
Consult a qualified specialist workshop immediatel y.
or #
Check whe ther you are permit tedto replace the light source yourself (/ page135).
% LED light sourc es:the display message forth e cor responding light appears only when allthe light-emitting
diodes in the light are faulty.
: Malfunction See Owner's
Manual *T
heexterior lighting is malfunctioning. #
Consult a qualified specialist workshop.
* Ve hicles with a trailer hitch: a fuse may haveblown. #
Stop theve hicle in accordance with the tra ffic conditions. #
Check the fuses and replace them if necessary (/ page 407).
: Automatic driving lights
inoperative *T
he light sensor is malfunctioning. #
Consult a qualified specialist workshop. Display messages and
warning/indicator lamps 451
Internal use only

Display messages
Possible causes/consequences and M
MSolutions
: Active Light System inoper-
ative *T
he active headlamp s are malfunctioning. #
Consult a qualified specialist workshop.
: Switch on headlamps *Y
ou are driving without lo w-beam headlamps. #
Turn the light switch totheL orà position.
:
Switch off lights *Y
ou are leaving theve hicle and the lights are still switched on. #
Turn the light switch totheà position.
: Intelligent Light System
inoperative *T
he Intelligent Light Sy stem is malfunctioning. The lighting sy stem continues tofunction proper lywithout the func‐
tions of the Intelligent Light Sy stem. #
Consult a qualified specialist workshop. 452
Display messages and warning/indicator lamps
Internal use only

Display messages
Possible causes/consequences and M
MSolutions #
Ifth e display message still appears, consult a qualified specialist workshop. Driving saf
ety sy stems Display messages
Possible causes/consequences and M
MSolutions
!
÷ currently unavailable See
Owner's Manual *
ABS and ESP ®
are temp orarily una vailable.
Other driving sy stems and driving saf ety sy stems (e.g. BAS) may also be temp orarily una vailable.
The brake sy stem will continue tooperate normally. Braking dis tance may increase in an emergency braking situa‐
tion. &
WARNING Risk of skidding if ABS and ESP ®
are malfunctioning
The wheels may lock du ring braking and ESP ®
does not pe rform any vehicle stabilisation.
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 carefully on a suitable stre tch of road, making slight steering mo vements at a speed abo ve30 km/h. #
Ifth e display message does not disappear, consult a qualified specialist workshop immediately. Drive care‐
full y. Displ
aymessa ges and warning/indicator lamps 481
Internal use only

Display messages
Possible causes/consequences and M
MSolutions
!
÷ inoperative See Owner's
Manual *
ABS and ESP ®
are malfunctioning.
Other driving sy stems and driving saf ety sy stems (e.g. BAS) may also be malfunctioning.
The brake sy stem will continue tooperate normally. Braking dis tance may increase in an emergency braking situa‐
tion. &
WARNING Risk of skidding if ABS and ESP ®
are malfunctioning
The wheels may block duri ng braking and ESP®
does not pe rform any vehicle stabilization.
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 ABS and ESP ®
ch ecked immediately at a qualified specialist workshop. ÷
currently unavailable See
Owner's Manual *
ESP ®
is temp orarily una vailable.
Other driving sy stems and driving saf ety sy stems (e.g. BAS) may also be malfunctioning. &
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. #
Drive carefully on a suitable stre tch of road, making slight steering mo vements at a speed abo ve30 km/h. 482
Displaymessa ges and warning/indicator lamps
Internal use only

Display messages
Possible causes/consequences and M
MSolutions
5 Engine oil pressure Stop
Switch off engine *D
isplay message only for cer tain engines:
The oil pressure is too lo w.
* NO
TEEngine damage causedbydriving with insuf ficient oil pressure #
Avoid driving with insuf ficient oil pressure. #
Stop theve hicle immediately in accordance with the traf fic conditions. Do not continue driving. #
Consult a qualified specialist workshop.
5 Engine oil level cannot be
measured *T
he electrical connection tothe oil le vel sensor has been inter rupte d or the oil le vel sensor is faulty. #
Consult a qualified specialist workshop. Wa
rning and indicator lamps Overview of indicator and
warning lamps Some sy
stems will per form a self-test when the
ignition is switched on. Some indicator and
wa rning lamps may briefly light up or flash. This
behaviour is non-critical. These indicator and wa
rning lamps indicate a malfunction only if they
light up or flash af terth e engine has been star‐
te d or during a journe y.498
Display messages and warning/indicator lamps
Internal use only

Instrument display (standard)
Wi
descreen cock pit 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 500)
ü Seat belt (/
page 500)
ï Trailer hit ch (/page 501)
Ù Powe rst eering (/ page 501)
ÿ Coolanttemp erature (/ page 502)
; Engine diagnostics (/
page 502)
% Preglow
# Elect
rical fault (/ page 502)
8 Re
ser vefuel with fuel filler flap loca‐
tion indicator (/ page 502)
! Elect
ric pa rking brake (red)
(/ page 505)
! Electric parking brake (yellow)
(/
page 505)
J Brakes (yellow) (/
page 505)
J Brakes (red) (/
page 505)
L Distance warning (/ page 507) ä
AIRMATIC (/ page 507)
ä DYNA MIC BODY CONTROL
(/ page 507)
! ABS (/
page 508)
÷ ESP®
(/ page 508)
å ESP®
OFF (/ page 508)
h Ty
re pressure monitoring sy stem
(/ page 511)
T St
anding lights (/ page125)
L Low beam (/
page125)
K High beam (/
page127)
#! Tu
rn signal lights (/ page127)
R Re
ar fog light (/ page125) Displ
aymessa ges and warning/indicator lamps 499
Internal use only

Occupant saf
ety Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
6 Re stra int sy stem warning
lamp *T
he redre stra int sy stem warning lamp is lit while the engine is running.
The restra int sy stem is malfunctioning (/ page 38). &
WARNING Risk of injury duetomalfunctions in there stra int sy stem
Components in there stra int sy stem may be activated unintentionally or not deploy as intended in an accident. #
Have there stra int sy stem checked and repaired immediately at a qualified specialist workshop. #
Drive on carefully. #
Notethe messages on the multifunction displa y. #
Consult a qualified specialist workshop immediatel y.
ü
Seat belt warning lamp *T
he red seat belt warning lamp flashes and an intermit tent wa rning tone sounds.
or
The red seat belt warning lamp lights up once the engine has star ted.
In addition, an intermittent warning tone may sound.
The red seat belt warning lamp flashes and an intermit tent wa rning tone sounds:
The driver or front passenger has not fastened his or her seat belt while theve hicle is in motion. #
Fasten your seat belt (/ page41).
There are objects on the front passenger seat. 500
Display messages and warning/indicator lamps
Internal use only

Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions #
Remo vethe objects from the front passenger seat.
The red seat belt warning lamp lights up once the engine has star ted:
In addition, an intermittent warning tone may sound.
The red seat belt warning lamp reminds the driver and front passenger tofasten their seat belts. #
Fasten your seat belt (/ page41).
If yo u ha veplaced objects on the front passenger seat, there d seat belt warning lamp may remain lit. Ve
hicle Wa
rning/indicator lamp
Possible causes/consequences and M
MSolutions
Ù Po we rst eering warning
lamp (red) *T
he red po werst eering sy stem warning lamp is lit while the engine is running.
The po wer assi stance or thesteering itself is malfunctioning. &
WARNING Risk of accident if steering capability is impaired
If th esteering does not function as intended, theve hicle's operating saf ety is jeopardised. #
Pull over and stop theve hicle safely as soon as possible, paying attention toroad and traf fic conditions. Do
not continue driving under any circums tances. #
Consult a qualified specialist workshop. #
Notethe messages on the multifunction displa y. Displ
aymessa ges and warning/indicator lamps 501
Internal use only