2011 MERCEDES-BENZ C-Class warning lights

Display messagesPossible causes/consequences and M SolutionsGRisk of accident
If the display message is shown and the ä warning lamp flashes
at the same time, ETS (Electronic Traction System) is deactivated.
The brakes on the drive wheels could otherwise overheat.
XLet the brakes cool down until the display message disappears
and the ä warning lamp goes out.
ETS is active again.G
Tele Aid
InoperativeUSA only: one or more main functions in the mbrace system are
malfunctioning.
Canada only: one or more of the main functions of the TELEAID
system is malfunctioning.XUSA only: have the mbrace system checked at a qualified
specialist workshop.XCanada only: have the TELEAID system checked at a qualified
specialist workshop.Check Child Seat
Pos.
See Operator's
ManualGRisk of injury
Vehicles with BabySmart™ (Canada only):
The BabySmart™ child seat is positioned incorrectly.
XInstall the child seat in the correct position.GRisk of injury
Vehicles with BabySmart™ (Canada only):
The sensor for automatic child seat recognition is faulty.
XVisit a qualified specialist workshop.6
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 SRS
Malfunction
Service Required
or
Front Right SRS
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.Display messages185On-board computer and displaysBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 185Z

Display messagesPossible causes/consequences and M Solutions6
Rear Left SRS
Malfunction
Service Required
or
Rear Right SRS
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.
186Display messagesOn-board computer and displays
BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 186

Display messagesPossible causes/consequences and M Solutions$ (USA only)
J (Canada only)
ABS and ESC
Inoperative See
Operator's ManualGRisk of accident
ABS, ESP ®
, BAS and hill start assist are unavailable due to a
malfunction. In addition, the ä, å and ! warning lamps
light up in the instrument cluster.
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.$ (USA only)
J (Canada only)
EBD, ABS, and ESC
Inoperative See
Operator's ManualGRisk of accident
EBD (Electronic Brake force Distribution), ABS, ESP ®
, BAS and hill
start assist are unavailable due to a malfunction. In addition, the
ä , å and ! warning lamps in the instrument cluster light
up and a warning tone sounds.
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 Park. BrakeYou are driving with the parking brake engaged. A warning tone
also sounds.XRelease the parking brake.$ (USA only)
J (Canada only)
Check Brake Fluid
LevelGRisk of accident
There is insufficient 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.190Display messagesOn-board computer and displays
BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 190

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.
Lights
i Display messages about LEDs:
This display message will only appear if all LEDs have failed.
Display messagesPossible causes/consequences and M Solutionsb
Check Left
Cornering Light
or
Check Right
Cornering LightThe left or right-hand cornering light is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 111).
or
XVisit a qualified specialist workshop.b
Check Left Low Beam
or
Check Right Low
BeamThe left or right-hand low-beam headlamp is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 111).
or
XVisit a qualified specialist workshop.b
Check Rear Left
Turn Signal
or
Check Rear Right
Turn SignalThe rear left-hand or rear right-hand turn signal is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 111).
or
XVisit a qualified specialist workshop.b
Check Front Left
Turn Signal
or
Check Front Right
Turn SignalThe front left-hand or front right-hand turn signal is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 111).
or
XVisit a qualified specialist workshop.Display messages191On-board computer and displaysBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 191Z

Display messagesPossible causes/consequences and M Solutionsb
Check Rear Left
Sidemarker Lamp
or
Check Rear Right
Sidemarker LampThe rear left or right side marker lamp is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 111).
or
XVisit a qualified specialist workshop.b
Check Left Daytime
Running Light
or
Check Right
Daytime Running
LightThe left or right-hand daytime running light is defective.XCheck whether you are permitted to change the bulb yourself
( Y page 111).
or
XVisit a qualified specialist workshop.b
Active Headlamps
InoperativeThe active light function is faulty.XVisit a qualified specialist workshop.b
Malfunction See
Operator's ManualThe exterior lighting is faulty.XVisit a qualified specialist workshop.b
Auto Lamp Function
InoperativeThe light sensor is faulty.XVisit a qualified specialist workshop.b
Switch Off LightsThe lights are still switched on when you leave the vehicle. A
warning tone also sounds.XTurn the light switch to c.
Engine
Display messagesPossible causes/consequences and M Solutions+
Check Coolant
Level See
Operator's ManualThe coolant level is too low.XAdd coolant, observing the warning notes when doing so
( Y page 240).XIf coolant needs adding more often than usual, have the engine
coolant system checked at a qualified specialist workshop.194Display messagesOn-board computer and displays
BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 194

GWarning
Driving with the brake warning lamp illuminated can result in an accident. Have your brake system
checked immediately if the brake warning lamp stays on. 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.
Seat belts
ProblemPossible causes/consequences and M Solutions7
After starting the
engine, the red seat
belt warning lamp lights
up for 6 seconds.The seat belt warning lamp reminds the driver and front passenger
to fasten their seat belts.XFasten your seat belt ( Y page 50).7
After starting the
engine, the red seat
belt warning lamp lights
up. In addition, a
warning tone sounds
for up to 6 seconds.GRisk of injury
The driver's seat belt is not fastened.
XFasten your seat belt ( Y page 50).
The warning tone ceases.7
The red seat belt
warning lamp lights up
after the engine starts,
as soon as the driver's
or the front-passenger
door is closed.GRisk of injury
The driver or front passenger has not fastened their seat belt.
XFasten your seat belt ( Y page 50).
The warning lamp goes out.GRisk of injury
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.204Warning and indicator lamps in the instrument clusterOn-board computer and displays
BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 204

EngineProblemPossible causes/consequences and M Solutions;
The yellow Check
Engine warning lamp
lights up while the
engine is running.There may be a malfunction, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R the fuel system
The emission limit values may have been exceeded and the engine
may be breaking in emergency mode.XHave the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you are required by law to visit a qualified
specialist workshop as soon as the Check Engine warning lamp
lights up. If necessary, check whether this is the case in the
state you are in.
8
The yellow reserve fuel
warning lamp flashes
while the engine is
running.The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.XCheck that the fuel filler cap is correctly closed.XIf the fuel filler cap is not correctly closed: close the fuel filler
cap.XIf the fuel filler cap is closed: visit a qualified specialist
workshop.8
The yellow reserve fuel
warning lamp lights up
while the engine is
running. The amount of fuel in the tank has dropped into the reserve range.XRefuel at the nearest gas station.?
The red coolant
warning lamp lights up
while the engine is
running and the coolant
temperature gauge is
at the start of the scale.The temperature sensor for the coolant temperature gauge is
faulty.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions. Do not continue
driving under any circumstances.XEngage the parking brake.XConsult a qualified specialist workshop.210Warning and indicator lamps in the instrument clusterOn-board computer and displays
BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 210

brake pads/linings. Generally, park the
vehicle at operating temperature after
cleaning.
Exterior care
Automatic car wash
GWarning!
Braking efficiency is reduced after washing
the vehicle. This could cause an accident. For
this reason, you must drive particularly
carefully after washing the vehicle until the
brakes have dried.
You can wash the vehicle in an automatic car
wash from the very start.
! Never clean your vehicle in a Touchless
Automatic Car Wash as these use special
cleaning agents. These cleaning agents can
damage the paintwork or plastic parts.
If the vehicle is very dirty, pre-wash it before
cleaning it in an automatic car wash.
! In car washes with a towing mechanism,
make sure that the automatic transmission
is in transmission position N, otherwise the
vehicle could be damaged.
! Make sure that the side windows are
completely closed, that the ventilation/
heating is switched off and that the
windshield wiper switch is set to 0.
Otherwise, the rain/light sensor could be
activated, triggering unintended wiper
movements. This can cause damage to the
vehicle.
After using an automatic car wash, wipe off
wax from the windshield and the wiper
blades. This will prevent smears and reduce
wiping noises caused by residue on the
windshield.
Washing by hand
Carefully remove all deposits of road salt as
soon as possible when driving in winter.
Also, clean the insides of the wheels when
washing the underbody of the vehicle.XDo not use hot water and do not wash the
vehicle in direct sunlight.XUse a soft car sponge for cleaning.XUse a gentle cleaning agent, e.g. a
Mercedes-Benz approved car shampoo.XWash down the vehicle with a gentle water
jet.XDo not point the water jet directly at the air
inlets.XUse plenty of water and rinse the sponge
frequently.XRinse the vehicle with clean water and dry
it thoroughly with a chamois.XDo not allow the cleaning agent to dry on
the paintwork.
Power washers
GWarning!
Do not use power washers with circular-jet
nozzles (dirt grinders) to clean your vehicle, in
particular the tires. You could otherwise
damage the tires and cause an accident.
! Keep the distance between the vehicle
and the nozzle of the power washer at
11.8 in (30 cm). Information about the
correct distance is available from the
equipment manufacturer.
Move the power washer nozzle around
when cleaning your vehicle.
Do not aim directly at any of the following:
R tires
R door joint
R electrical components
R battery
R connectors
R lights
R seals
R trim elements
R ventilation slots
244CareMaintenance and care
BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 244