MERCEDES-BENZ C-CLASS SALOON 2012 Owners Manual

Display messages
Possible causes/consequences and M
MSolutions &
WARNING Risk of injury or death when using a child restra int sy stem while the front passenger airbag is
enabled
If yo u secure a child in a child restra int sy stem on the front passenger seat and the front passenger airbag is
enabled, the front passenger airbag can deploy in theeve nt of an accident.
The child could be stru ck bythe airbag. #
Ensure, bo thbefore and during the journe y,that thest atus of the front passenger airbag is cor rect.
NEVER use a rear wa rdfacing child restra int on a seat pr otected byan ACTIVE AIRB AGin front of it, DE ATH or
SERIOUS INJU RYtotheCH ILD can occur. #
Stop theve hicle immediately in accordance with the traf fic conditions. #
Makesure that no objects are trapped under the front passenger seat. #
Check thest atus of automatic front passenger airbag actuation (/ page 48).#
If necessar y,consult a qualified specialist workshop immediatel y.
PRE-SAFE inoperative See
Owner's Manual *
The PRE‑SAFE ®
functions are malfunctioning. #
Consult a qualified specialist workshop. 448
Displaymessa ges and warning/indicator lamps
Internal use only

Key
Display messages
Possible causes/consequences and M
MSolutions
Á Replace key *H
avetheke yre placed. #
Consult a qualified specialist workshop.
Á Change key batteries *T
hekey bat tery is dischar ged. #
Replace the battery (/ page75).
Á
Key not detected (white dis‐
play message) *T
hekey is cur rently und etected. #
Change the location of theke y in theve hicle. #
Ifth eke y is still not recognised, place it in the slot forst arting with theke y (/ page156). Displ
aymessa ges and warning/indicator lamps 449
Internal use only

Display messages
Possible causes/consequences and M
MSolutions
Á Key not detected (red dis‐
play message) *T
hekey cannot be de tected and may no longer be in theve hicle.
The key is no lon ger in theve hicle and you swit choff the engine:
R You can no lon gerst art the engine.
R You cannot centrally lock theve hicle. #
Ensure that theke y is in theve hicle.
If th eke y de tection function has a malfunction due toast ro ng radio signal source: #
Stop theve hicle immediately in accordance with the traf fic conditions. #
Place theke y in the slot forst arting the engine with theke y (/ page156).
Place the key in the
marked space See Owner's
Manual *K
eydetection is malfunctioning. #
Change the location of theke y in theve hicle. #
Place theke y in the slot forst arting the engine with theke y (/ page156). 450
Displaymessa ges and warning/indicator lamps
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
Adaptive Highbeam Assist
currently unavailable See
Owner's Manual *A
daptive Highbeam Assist is temp orarily una vailable.
The sy stem limits ha vebeen reached (/ page130).
On ce the cause of the problem is no longer present, the sy stem will be available again. The Adaptive Highbeam
Assist available again display message will appear. #
Drive on. #
Operate the high beam manually until Adaptive High Beam Assist is available again.
Adaptive Highbeam Assist
inoperative *A
daptive Highbeam Assist is malfunctioning. #
Consult a qualified specialist workshop.
Adaptive Highbeam Assist
Camera view restricted
See Owner's Manual *T
he camera view is restricted. Possible causes:
R dirt on the windscreen in the camera's field of vision
R heavy rain, snow or fog
Driving sy stems and driving saf ety sy stems may be malfunctioning or temp orarily una vailable.
Once the cause of the problem is no longer present, the driving sy stems and driving saf ety sy stems will be available
again.
If th e display message does not disappear: #
Stop theve hicle in accordance with the tra ffic conditions. #
Clean the windscreen. Display messages and
warning/indicator lamps 453
Internal use only

Display messages
Possible causes/consequences and M
MSolutions
Adaptive Highbeam Assist
Plus currently unavailable
See Owner's Manual *A
daptive Highbeam Assist Plus is temp orarily una vailable.
The sy stem limits ha vebeen reached (/ page132).
On ce the cause of the problem is no longer present, the sy stem will be available again. The Adaptive Highbeam
Assist Plus available again display message will appear. #
Drive on. #
Operate the high beam manually until Adaptive High Beam Assist Plus is available again.
Adaptive Highbeam Assist
Plus inoperative *A
daptive Highbeam Assist Plus is malfunctioning. #
Consult a qualified specialist workshop.
Adaptive Highbeam Assist
Plus Camera view restric-
ted See Owner's Manual *T
he camera view is restricted. Possible causes:
R dirt on the windscreen in the camera's field of vision
R heavy rain, snow or fog
Driving sy stems and driving saf ety sy stems may be malfunctioning or temp orarily una vailable.
Once the cause of the problem is no longer present, the driving sy stems and driving saf ety sy stems will be available
again.
If th e display message does not disappear: #
Stop theve hicle in accordance with the tra ffic conditions. #
Clean the windscreen. 454
Display messages and warning/indicator lamps
Internal use only

Display messages
Possible causes/consequences and M
MSolutions
Hazard warning lamps mal-
functioning *T
he hazard warning lamp switch is malfunctioning. #
Consult a qualified specialist workshop. Climate control
Display messages
Possible causes/consequences and M MSolutions
& inoperative See Owner's
Man. *T
hestationary heater is temp orarily malfunctioning. #
When theve hicle is stationary on a le vel sur face and the engine has cooled down, make up tofour attem ptsto
switch on thest ationary heater, waiting se veral minutes between each attem pt. #
Ifth est ationary heater does not swit chon, consult a qualified specialist workshop.
&
inoperative Battery low *T
he on-board electrical sy stem voltage is too lo w.
The stationary heater has swit ched itself off. #
Drive an extended di stance until the battery has reached a suf ficient charge leve l again.
&
inoperative Refuel vehicle *T
here is too little fuel in the fuel tank. The stationary heater cannot be swit ched on. #
Refuel theve hicle. Display messages and
warning/indicator lamps 455
Internal use only

Ve
hicle Display messages
Possible causes/consequences and M
MSolutions
d Vehicle is operational
Switch off ignition before
exiting *Y
ou are leaving theve hicle in a ready-to-drive state. #
When you lea vetheve hicle, switch off the ignition, secure theve hicle against rolling away and take theke y with
yo u. #
Ifyo u do not lea vetheve hicle, switch off the electrical consumers, e.g. the seat heating. Otherwise, the12 V
battery may dischar geand it will then be possible tostart theve hicle only with the aid of a second battery
(s ta rting assis tance).
ï Check trailer hitch lock *T
he trailer hitch is not operational during a journey with a trailer. &
WARNING Risk of an accident if the ball neck is not loc ked
The trailer may become de tach ed. #
Stop theve hicle immediately in accordance with the traf fic conditions. Do not continue driving. #
Uncouple the trailer and secure it against rolling away. #
Initiate a new swivel mo vement and do not re-couple the trailer until thewa rning/indicator lamp goes out. #
Initiate a new swivel mo vement (/ page 237). #
When the display message disappears, couple up the trailer and drive on.
If th e display message does not disappear, the trailer hitch is malfunctioning and the ball neck is not loc ked. 456
Display messages and warning/indicator lamps
Internal use only

Display messages
Possible causes/consequences and M
MSolutions #
Do not couple up the trailer. Drive on without the trailer. No tethere duced ground clearance due tothe
unlo cked ball nec k. #
Consult a qualified specialist workshop.
*T he trailer hitch will not be operational when theve hicle is stationar y. #
Uncouple the coupled trailer and secure it against rolling away. #
Ifth e ball neck has been folded in: unlockthe ball neck (/ page 237). #
Swivel the ball neck into the end position manually and let it engage. #
Ifth e ball neck has been folded out: unlockthe ball neck (/ page 237). #
Swivel the ball neck beneath the bumper manually and let it engage.
If th e display message does not disappear, the trailer hitch is malfunctioning and the ball neck is not loc ked. #
Do not couple up the trailer. Drive on without the trailer. No tethere duced ground clearance due tothe
unlo cked ball nec k. #
Consult a qualified specialist workshop.
Ù Steering malfunction
Increased physical effort
See Owner's Manual *T
he po werst eering assis tance is malfunctioning. &
WARNING Risk of an accident due toaltered steering characteristics
If th e po wer assi stance of thesteering fails partially or comple tely, you will need touse more forc eto steer. #
If safe steering is possible, drive on carefully. Display messages and
warning/indicator lamps 457
Internal use only