2012 MERCEDES-BENZ C-Class COUPE check engine

GWARNING
The SRS self-check has detected a
malfunction if the 6 SRS warning lamp:
R does not come on at all
R fails to go out approximately 4 seconds
after the engine was started
R comes on after the engine was started or
while driving
For your safety, Mercedes-Benz strongly
recommends that you have the system
checked as soon as possible at an authorized
Mercedes-Benz Center. Otherwise the SRS
may not be activated when it is needed in an
accident, which could result in serious or fatal
injury. The SRS might also deploy
unexpectedly and unnecessarily which could
also result in injury.
In addition, improper work on the SRS creates
a risk of rendering the SRS inoperative or
causing unintended air bag deployment. Work
on the SRS must therefore only be performed
by qualified technicians. Contact an
authorized Mercedes-Benz Center.
If it is necessary to modify an air bag system
to accommodate a person with disabilities,
contact an authorized Mercedes-Benz Center
for details. USA only: Call our Customer
Assistance Center at 1-800-FOR-MERCedes
(1-800-367-6372) for details.
Safety guidelines for seat belts,
Emergency Tensioning Devices (ETDs)
and air bags
GWARNING
R Damaged seat belts or seat belts that have
been subjected to stress in an accident
must be replaced. Their anchoring points
must also be checked. Only use seat belts
installed or supplied by an authorized
Mercedes-Benz Center.
R Air bags and pyrotechnic Emergency
Tensioning Devices (ETDs) contain
perchlorate material, which may require
special handling and regard for the
environment. Check your national disposal
guidelines. California residents, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm .
R Air bags and ETDs are designed to function
on a one-time-only basis. An air bag or ETD
that has deployed must be replaced.
R Do not pass seat belts over sharp edges.
They could tear.
R Do not make any modification that could
change the effectiveness of the seat belts.
R Do not bleach or dye seat belts as this may
severely weaken them. In a crash they may
not be able to provide adequate protection.
R No modifications of any kind may be made
to any components or wiring of the SRS.
R Do not change or remove any component
or part of the SRS.
R Do not install additional trim material, seat
covers, badges, etc. over the steering
wheel hub, front-passenger front air bag
cover, outer sides of the seat backrests,
door trim panels, or door frame trims.
R Do not install additional electrical/
electronic equipment on or near SRS
components and wiring.
R Keep area between air bags and occupants
free of objects (e.g. packages, purses,
umbrellas, etc.).
R Do not hang items such as coat hangers
from the coat hooks or handles over the
door. These items may be thrown around in
the vehicle and cause head and other
injuries when the window curtain air bag is
deployed.
R Air bag system components will be hot after
an air bag has inflated. Do not touch them.
R Never place your feet on the instrument
panel, dashboard, or on the seat. Always
keep both feet on the floor in front of the
seat.
R Improper repair work on the SRS creates a
risk of rendering the SRS inoperative or
causing unintended air bag deployment.
Work on the SRS must therefore only beOccupant safety37SafetyZ

of the radar sensors checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle.
If BAS PLUS is not available due to a
malfunction in the radar sensor system, the
brake system remains available with full
brake boosting effect and BAS.
ESP ®
(Electronic Stability Program)
Important safety notes
i See the "Important safety notes" section
( Y page 56).
If ESP ®
detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilize the
vehicle. If necessary, the engine output is also
modified to keep the vehicle on the desired
course within physical limits. ESP ®
assists
the driver when pulling away on wet or
slippery roads. ESP ®
can also stabilize the
vehicle during braking.
If ESP ®
intervenes, the ÷ ESP®
warning
lamp flashes in the instrument cluster.
GWARNING
Under no circumstances should you
deactivate ESP ®
when the ÷ ESP®
warning lamp in the instrument cluster
flashes. Proceed as follows:
R when driving off, apply as little throttle as
possible.
R while driving, ease up on the accelerator
pedal.
R adapt your speed to suit the prevailing road
and weather conditions.
Failure to observe these guidelines could
cause the vehicle to skid. ESP ®
cannot
prevent accidents resulting from excessive
speed.
! Switch the ignition off when:
R the parking brake is being tested using a
dynamometer
R the vehicle is being towed with the front
or rear axle raised
Application of the brakes by ESP ®
may
otherwise destroy the brake system.
i Only use wheels with the recommended
tire sizes. Only then will ESP ®
function
properly.
ETS (Electronic Traction System)
i Observe the "Important safety notes"
section ( Y page 56).
Traction control is part of ESP ®
.
If the drive wheels spin, traction control
brakes them individually. This enables you to
pull away and accelerate on slippery surfaces,
for example if the road surface is slippery on
one side.
Traction control remains active if you
deactivate ESP ®
.
Deactivating/activating ESP ®
(except
AMG vehicles)
GWARNING
ESP ®
should not be deactivated during
normal driving other than in the
circumstances described below. Disabling
the system will reduce vehicle stability in
driving maneuvers.
Do not deactivate ESP ®
when the emergency
or spare wheel is mounted.
ESP ®
is activated automatically when the
engine is started.
It may be best to deactivate ESP ®
in the
following situations:
R when using snow chains
R in deep snow
R on sand or gravel
Driving safety systems59SafetyZ

In these cases, PRE-SAFE(R) Brake may:
R give an unnecessary warning and then
brake the vehicle
R neither give a warning nor intervene
There is a risk of an accident. Always pay
particular attention to the traffic situation and
be ready to brake, especially if PRE-SAFE(R)
Brake warns you. Terminate the intervention
in a non-critical driving situation.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or anything else
covering the sensors
R snow or heavy rain
R interference by other radar sources
R the possibility of strong radar reflections,
for example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different lineGWARNING
PRE-SAFE ®
Brake does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R in curves
As a result, PRE-SAFE ®
Brake cannot
intervene in critical situations. There is a risk
of an accident. Always pay careful attention
to the traffic situation and be ready to brake.
In order to maintain the appropriate distance
to the vehicle in front and thus prevent a
collision, you must apply the brakes yourself.
XTo activate/deactivate: activate or
deactivate PRE-SAFE ®
Brake in the on-
board computer ( Y page 193).
The Ä symbol appears in the
multifunction display as long as the HOLD
function is not activated ( Y page 159).
On vehicles with Parking Guidance, the
Ä symbol is displayed whentransmission position P is selected or if you
drive faster than 22 mph (35 km/h).
For PRE-SAFE ®
Brake to assist you when
driving, the radar sensor system must be
switched on ( Y page 196) and operational.
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensors checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle.
Theft deterrent locking systems
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
SmartKey that is left inside the vehicle.
XTo activate with the SmartKey: remove
the SmartKey from the ignition lock.XTo activate with KEYLESS-GO: switch the
ignition off and open the driver's door.XTo deactivate: switch on the ignition.
i
The immobilizer is always deactivated
when you start the engine.
In the event that the engine cannot be
started when the starter battery is fully
charged, the immobilizer may be faulty.
Contact an authorized Mercedes-Benz
Center or call 1-800-FOR-MERCedes (in
USA) or 1-800-387-0100 (in Canada).
ATA (Anti-Theft Alarm system)
A visual and audible alarm is triggered if the
alarm system is armed and you open:
R a door
R the vehicle with the mechanical key
R the trunk lid
R the hood
64Theft deterrent locking systemsSafety

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 23).
SmartKey
Important safety notes
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.GWARNING
If a key ring is too heavy or too large, the
weight acting on the SmartKey could cause it
to turn in the ignition lock or catch on the
steering wheel. This could cause the engine
to be switched off suddenly. You could lose
control of the vehicle and cause an accident.
Do not attach any heavy or large key rings to
the SmartKey that is inserted in the ignition.
General notes
If you cannot lock or unlock the vehicle with
the SmartKey, either the battery in the
SmartKey is discharged, the SmartKey is
faulty or the starter battery is discharged.
XCheck the battery in the SmartKey and
replace it if necessary ( Y page 72).XUnlock the driver's door using the
mechanical key ( Y page 77).XLock the vehicle using the mechanical key
( Y page 77).XHave the starter battery and the battery
contacts checked at a qualified specialist
workshop.
If the SmartKey is faulty, contact Roadside
Assistance or a qualified specialist workshop.
SmartKey functions
General notes
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
68SmartKeyOpening/closing

ProblemPossible causes/consequences and M SolutionsThe engine cannot be
started using the
SmartKey.The on-board voltage is too low.XSwitch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
XCheck the starter battery and charge it if necessary
( Y page 284).
or
XJump-start the vehicle ( Y page 287).
or
XConsult a qualified specialist workshop.The engine cannot be
started using the
SmartKey.The steering lock is mechanically blocked.XRemove the SmartKey and reinsert it into the ignition lock. While
doing this, turn the steering wheel in both directions.The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle.A door is open. Therefore, the SmartKey cannot be detected as
easily.XClose the door and try to start the vehicle again.There is interference from a powerful source of radio waves.XStart your vehicle with the SmartKey in the ignition lock.Doors
Important safety notes
GWARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts.GWARNING
Do not carry heavy or hard objects in the
passenger compartment or trunk unless they
are firmly secured in place.
Doors75Opening/closingZ

XDrive with the headlamps switched on.
The level of moisture diminishes,
depending on the length of the journey and
the weather conditions (humidity and
temperature).
If the level of moisture does not diminish:
XHave the headlamps checked at a qualified
specialist workshop.
Interior lighting
Overview of interior lighting
:u Switches the rear interior lighting
on/off;| Switches the automatic interior
lighting control on/off=p Switches the right-hand front
reading lamp on/off?c Switches the front interior lighting
on/offAp Switches the left-hand front reading
lamp on/off
Interior lighting control
Important notes
In order to prevent the vehicle's battery from
discharging, the interior lighting functions are
automatically deactivated after some time
except for when the SmartKey is in position
2 in the ignition lock.
Automatic interior lighting controlXTo switch on/off: press the | button.
When the automatic interior lighting
control is activated, the button is flush with
the overhead control panel.
The interior lighting automatically switches
on if you:
R unlock the vehicle
R open a door
R remove the SmartKey from the ignition lock
The interior light is activated for a short while
when the SmartKey is removed from the
ignition lock. You can activate this delayed
switch-off using the on-board computer
( Y page 196).
Manual interior lighting control
XTo switch the interior lighting on/off:
press the c button.XTo switch the reading lamps on/off:
press the p button.
Crash-responsive emergency lighting
The interior lighting is activated automatically
if the vehicle is involved in an accident.
XTo switch off the crash-responsive
emergency lighting: press the hazard
warning lamp button.
or
XLock and then unlock the vehicle using the
SmartKey.
Replacing bulbs
Important safety notes
Xenon bulbs
If your vehicle is equipped with Xenon bulbs,
you can recognize this by the following: the
cone of light from the Xenon bulbs moves
from the top to the bottom and back again
when you start the engine. For this to be
106Replacing bulbsLights and windshield wipers

observed, the lights must be switched on
before starting the engine.GDANGER
Xenon bulbs carry a high voltage. You could
get an electric shock and be seriously or even
fatally injured if you touch the electric
contacts on Xenon bulbs. Therefore, never
remove the cover from Xenon bulbs.
Do not change Xenon bulbs yourself, but have
them replaced at a qualified specialist
workshop which has the necessary specialist
knowledge and tools to carry out the work
required.
Mercedes-Benz recommends that you use an
authorized Mercedes-Benz Center for this
purpose. In particular, work relevant to safety
or on safety-related systems must be carried
out at a qualified specialist workshop.
Bulbs and lamps are an important aspect of
vehicle safety. You must therefore make sure
that these function correctly at all times.
Have the headlamp setting checked regularly.
Other bulbs
There are bulbs other than the Xenon bulbs
that you cannot replace. Replace only the
bulbs listed (Y page 107). Have the bulbs that
you cannot replace yourself changed at a
qualified specialist workshop.
Mercedes-Benz recommends that you use an
authorized Mercedes-Benz Center for this
purpose. In particular, work relevant to safety
or on safety-related systems must be carried
out at a qualified specialist workshop.
If you require assistance changing bulbs,
consult a qualified specialist workshop.
Do not touch the glass tube of new bulbs with
your bare hands. Even minor contamination
can burn into the glass surface and reduce
the service life of the bulbs. Always use a lint-
free cloth or only touch the base of the bulb
when installing.
Only use bulbs of the correct type.
If the new bulb still does not light up, consult
a qualified specialist workshop.
Bulbs and lamps are an important aspect of
vehicle safety. You must therefore make sure
that these function correctly at all times.
Have the headlamp setting checked regularly.GWARNING
Bulbs and lamps can be very hot. You should
therefore allow them to cool down before you
change them. Otherwise, you could be burned
if you touch them.
Keep bulbs out of the reach of children.
Otherwise, they could damage the bulbs, for
example, and injure themselves.
Never use a bulb which has been dropped.
Such a bulb may break or even explode and
injure you.
Halogen bulbs are pressurized and can
explode when you change them, particularly
if they are very hot. You should therefore wear
eye protection and gloves when you are
changing them.
Overview: changing bulbs/bulb types
You can change the following bulbs. The bulb
type can be found in the legend.
Halogen headlamps
:Parking lamp/standing lamp: W 5 W;High-beam headlamp: H7 55 W=Low-beam headlamp: H7 55 WReplacing bulbs107Lights and windshield wipersZ

XRemove the wiper blade from the retaining
pin on the wiper arm in the direction of the
arrow.
Installing the wiper blades
XPush the new wiper blade onto the
retaining pin on the wiper arm in the
opposite direction to the arrow.
Make sure that the wiper blade slides fully
onto the retaining pin on the wiper arm.XTurn the wiper blade parallel to the wiper
arm.XFold the wiper arm back onto the
windshield.
Problems with the windshield wipers
The windshield wipers are obstructed
Leaves or snow, for example, may be
obstructing the windshield wiper movement.
The wiper motor has been deactivated.
XFor safety reasons, you should remove the
SmartKey from the ignition lock.
or
XSwitch off the engine using the Start/Stop
button and open the driver's door.XRemove the cause of the obstruction.XSwitch the windshield wipers back on.
The windshield wipers are inoperative
The windshield wiper drive is malfunctioning.
XSelect another wiper speed on the
combination switch.XHave the windshield wipers checked at a
qualified specialist workshop.
The spray nozzles are misaligned
The windshield washer fluid from the spray
nozzles no longer hits the center of the
windshield. The spray nozzles are misaligned.
XHave the spray nozzles adjusted at a
qualified specialist workshop.112Windshield wipersLights and windshield wipers