2012 MERCEDES-BENZ C-Class SEDAN warning light

! If the coolant temperature is too high a
display message is shown.
If the coolant temperature rises above
248 ‡(120 †), do not drive any further as
this could damage the engine.
Tachometer
The red band in the tachometer indicates the
engine's overrevving range.
! Do not drive in the overrevving range, as
this could damage the engine.
The fuel supply is interrupted to protect the
engine when the red band is reached.
Outside temperature display
The outside temperature display is in the
multifunction display ( Y page 196).
GWARNING
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges.
Changes in the outside temperature are
displayed after a short delay.
Speedometer with segments
The segments in the speedometer indicate
which speed range is available.
Cruise control ( Y page 159) activated:
The segments light up from the stored speed
to the maximum speed.
DISTRONIC PLUS ( Y page 161) activated:
One or two segments in the set speed range
light up.
DISTRONIC PLUS detects a vehicle in front:
The segments between the speed of the
vehicle in front and the stored speed light up.
Operating the on-board computer
Overview
The on-board computer is activated as soon
as you turn the SmartKey to position 1 in the
ignition lock.
You can control the multifunction display and
the settings in the on-board computer using
the buttons on the multifunction steering
wheel.
:Multifunction display;To switch on the Voice Control System;
see the separate operating instructions=Right control panel?Left control panelABack buttonDisplays and operation195On-board computer and displaysZ

Menus and submenus
Menu overview
The number of menus shown depends on the optional equipment in the vehicle.
Function:Trip menu ( Y page 199);Navi menu (navigation details) ( Y page 200)=Audio menu ( Y page 201)?Tel menu (telephone) ( Y page 202)ADriveAssist menu (assistance) ( Y page 204)BServ. menu ( Y page 206)
R calls up display messages ( Y page 213)
R tire pressure loss warning system (Canada only) ( Y page 317)
R tire pressure monitor ( Y page 319)
R ASSYST PLUS service interval display ( Y page 282)CSett. menu ( Y page 206)DAMG menu in AMG vehicles ( Y page 210)
The Audio and Tel menus differ slightly in vehicles with an audio system and vehicles with
COMAND. The examples given in this Operator's Manual apply to vehicles equipped with
COMAND.
198Menus and submenusOn-board computer and displays

Service menu
In the Serv. menu you can:
R call up display messages ( Y page 213)
R restart the tire pressure loss warning
system (Canada only) ( Y page 317)
R check the tire pressure electronically
( Y page 319)
R call up the service due date ( Y page 282)
Settings menu
Introduction
The Sett. menu can be used for:
R changing the instrument cluster settings
R changing the light settings
R changing the vehicle settings
R changing the convenience settings
R restoring the factory settings
Instrument cluster
Selecting the unit of measurement for
distance
The Display Unit Speed-/Odometer:
function allows you to choose whether
certain displays appear in kilometers or miles.
The selected unit of measurement for
distance applies to:
R the digital speedometer in the Trip menu
R the odometer and the trip odometer
R the trip computer
R the current consumption and the range
R the navigation instruction in the Navi menu
R DISTRONIC PLUS
R ASSYST PLUS service interval displayXPress the = or ; button on the
steering wheel to select the Settings
menu.XPress the : or 9 button to select the
Instr. cluster submenu.XPress the a button to confirm.XPress the : or 9 button to select the
Display Unit Speed-/Odometer
function.
You will see the selected setting: km or
miles .XPress the a button to save the setting.
Selecting the permanent display function
The Permanent Display: function allows
you to choose whether the multifunction
display always shows the outside
temperature or the speed in km/h (USA) or
mph (Canada).
XPress the = or ; button on the
steering wheel to select the Settings
menu.XPress the : or 9 button to select the
Instr. cluster submenu.XPress the a button to confirm.XPress the : or 9 button to select the
Permanent display function.
You will see the selected setting Outside
Temperature or Speedometer [km/h]: .XPress the a button to save the setting.206Menus and submenusOn-board computer and displays

Safety systemsDisplay messagesPossible causes/consequences and M Solutions!÷
Currently
Unavailable See
Operator's ManualGRisk of accident
ABS (Anti-lock Braking System), ESP ®
(Electronic Stability
Program), BAS (Brake Assist), the HOLD function and hill start
assist are temporarily unavailable.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
The self-diagnosis function might not be complete, for example.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XCarefully drive a suitable distance making slight steering
movements at a speed above 12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.GRisk of accident
ABS, ESP ®
, BAS, the HOLD function and hill start assist are
temporarily unavailable.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
For example, the on-board voltage may be insufficient.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.214Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M Solutions!÷
Inoperative See
Operator's ManualGRisk of accident
ABS, ESP ®
, BAS, the HOLD function and hill start assist are
unavailable due to a malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
The $ (USA only)/ J (Canada only), ÷, å
and ! warning lamps in the instrument cluster also light up.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
ATTENTION ASSIST is deactivated.
XDrive on carefully.XVisit a qualified specialist workshop immediately.÷
Currently
Unavailable See
Operator's ManualGRisk of accident
ESP ®
, BAS, the HOLD function and hill start assist are temporarily
unavailable.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷ and å warning lamps light up in the
instrument cluster.
The self-diagnosis function might not be complete, for example.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above.
XCarefully drive a suitable distance making slight steering
movements at a speed above 12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.Display messages215On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutions÷
Inoperative See
Operator's ManualGRisk of accident
ESP ®
, BAS, the HOLD function and hill start assist are unavailable
due to a malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷ and å warning lamps light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above.
XDrive on carefully.XVisit a qualified specialist workshop.T !
÷
Inoperative See
Operator's ManualGRisk of accident
EBD (electronic brake force distribution), ABS, ESP ®
, BAS, the
HOLD function and hill start assist are unavailable due to a
malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster and a warning tone sounds.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.XVisit a qualified specialist workshop immediately.#
Check Brake Pad
WearThe brake pads/linings have reached their wear limit.XVisit a qualified specialist workshop.$ (USA
only) J (Canada
only)
Release Parking
BrakeYou are driving with the parking brake applied. A warning tone also
sounds.XRelease the parking brake.216Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M Solutions$ (USA
only) J (Canada
only)
Brake ImmediatelyA malfunction has occurred while the HOLD function or
DISTRONIC PLUS is active.
A tone may also sound at regular intervals. The tone becomes
louder if you attempt to lock the vehicle.
You cannot start the engine.XPaying attention to the traffic situation, immediately depress the
brake pedal firmly and hold until the display message
disappears.XPrevent the vehicle from rolling away before you leave it
( Y page 294).
You can restart the engine.$ (USA
only) J (Canada
only)
Check Brake Fluid
LevelGRisk of accident
There is not enough brake fluid in the brake fluid reservoir.
Additionally, the red $ (USA only)/ J (Canada only)
warning lamp lights up in the instrument cluster and a warning
tone sounds.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.XEngage the parking brake.XConsult a qualified specialist workshop.XDo not add brake fluid. This will not rectify the malfunction.GWARNING
Driving with the message Check Brake Fluid Level displayed can result in an accident. Have
your brake system checked immediately.
Do not add brake fluid before checking the brake system. Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot engine parts and the brake fluid catching fire. You can be
seriously burned.
Display messages217On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutions6
SRS Malfunction
Service RequiredGRisk of injury
There is a malfunction in the SRS (Supplemental Restraint
System). The 6 warning lamp also lights up in the instrument
cluster.
XVisit a qualified specialist workshop.6
Front Left
Malfunction
Service Required or
Front Right
Malfunction
Service RequiredGRisk of injury
SRS has malfunctioned at the front on the left or right. The 6
warning lamp also lights up in the instrument cluster.
XVisit a qualified specialist workshop.6
Rear Left
Malfunction
Service Required or
Rear Right
Malfunction
Service RequiredGRisk of injury
SRS has malfunctioned at the rear on the left or right. The 6
warning lamp also lights up in the instrument cluster.
XVisit a qualified specialist workshop.6
Rear Center SRS
Malfunction
Service RequiredGRisk of injury
SRS has malfunctioned at the rear center. The 6 warning lamp
also lights up in the instrument cluster.
XVisit a qualified specialist workshop.6
Left Side Curtain
Airbag Malfunction
Service Required or
Right Side Curtain
Airbag Malfunction
Service RequiredGRisk of injury
There is a malfunction in the left-hand and/or right-hand window
curtain air bag. The 6 warning lamp also lights up in the
instrument cluster.
XVisit a qualified specialist workshop.GWARNING
In the event a malfunction of the SRS is indicated as outlined above, the SRS may not be
operational.
For your safety, we strongly recommend that you contact an authorized Mercedes-Benz Center
immediately to have the system checked. Otherwise the SRS may not be activated when needed
in an accident, which could result in serious or fatal injury, or it might deploy unexpectedly and
unnecessarily which could also result in injury.
Display messages219On-board computer and displaysZ