2012 MERCEDES-BENZ C-Class SEDAN 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

For safety reasons, Mercedes-Benz
recommends that you only use seat
accessories which have been approved by
Mercedes-Benz.
Both the driver and the passenger should
always use the 45 indicator lamp as
an indication of whether or not the passenger
is properly positioned.GWARNING
If the 45 indicator lamp illuminates
when an adult or someone larger than a small
individual is in the front passenger seat, have
the front passenger reposition himself or
herself in the seat until the 45
indicator lamp goes out.
In the event of a collision, the air bag control
unit will not allow front passenger front air bag
deployment when the OCS has classified the
front passenger seat occupant as weighing as
much as or less than a typical 12-month-old
child in a standard child restraint or if the front
passenger seat is classified as being empty.
When the OCS senses that the front
passenger seat occupant is classified as
being up to or less than the weight of a typical
12-month-old child in a standard child
restraint, the 45 indicator lamp will
illuminate when the engine is started and
remain illuminated. This indicates that the
front passenger front air bag is deactivated.
When the OCS senses that the front
passenger seat is classified as being empty,
the 45 indicator lamp will illuminate
when the engine is started and remain
illuminated. This indicates that the front
passenger front air bag is deactivated.
When the OCS senses that the front
passenger seat occupant is classified as
being heavier than the weight of a typical 12-
month-old child seated in a standard child
restraint or as being a small individual (such
as a young teenager or a small adult), the
45 indicator lamp will illuminate for
approximately 6 seconds when the engine is
started. Depending on occupant weight
sensor readings from the seat, it will then
remain illuminated or go out. With the
45 indicator lamp illuminated, the
front passenger front air bag is deactivated.
With the 45 indicator lamp out, the
front passenger front air bag is activated.
When the OCS senses that the front
passenger seat occupant is classified as an
adult or someone larger than a small
individual, the 45 indicator lamp will
illuminate for approximately six seconds
when the engine is started and then go out.
This indicates that the front passenger front
air bag is activated.
If the 45 indicator lamp is illuminated,
the front passenger front air bag is
deactivated and will not be deployed.
If the 45 indicator lamp is not
illuminated, the front passenger front air bag
is activated and will be deployed
R in the event of certain frontal impacts
R if the impact exceeds a predetermined
triggering threshold
R independent of the side impact air bag or
pelvis air bag
If the front passenger front air bag is
deployed, the rate of inflation will be
influenced by
R the rate of vehicle deceleration as assessed
by the air bag control unit
R the front passenger's weight category as
identified by the OCS
For further information, see "Air bag display
messages" ( Y page 221).GWARNING
According to accident statistics, children are
safer when properly restrained on the rear
seats than on the front-passenger seat. Thus,
we strongly recommend that children be
placed in the rear seats whenever possible.
Regardless of seating position, children 12
years old and under must be seated and
properly secured in an appropriate infant
restraint, toddler restraint, or booster seat
Occupant safety43SafetyZ

XIf necessary, adjust the seat belt to the
appropriate height ( Y page 51).XIf necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
All seat belts except the driver's seat belt are
equipped with a special seat belt retractor to
securely fasten child restraint systems in the
vehicle. For further information on special
seat belt retractors, see ( Y page 55).
For more information about releasing the seat
belt with release button ?, see "Releasing
seat belts" ( Y page 51).
Belt height adjustment
You can adjust the seat belt height on the
driver's seat and the front-passenger seat.
Adjust the height so that the upper part of the
seat belt is routed across the center of your
shoulder.
XTo raise: slide the belt sash guide upwards.
The belt sash guide engages in various
positions.XTo lower: press and hold belt sash guide
release :.XSlide the belt sash guide downwards.XRelease belt sash guide release : and
make sure that the belt sash guide has
engaged.Releasing seat beltsXPress release button ?(Y page 50) and
guide belt tongue ; back towards belt
sash guide :.
!
Make sure that the seat belt is fully rolled
up. Otherwise, the seat belt or belt tongue
will be trapped in the door or in the seat
mechanism. This could damage the door,
the door trim panel and the seat belt.
Damaged seat belts can no longer fulfill
their protective function and must be
replaced. Consult an authorized Mercedes-
Benz Center.
Belt warning for the driver and front
passenger
Regardless of whether the driver and front
passenger have fastened their seat belts
already, the 7 seat belt warning lamp
lights up for 6 seconds after every engine
start. It then goes out if the driver and the
front passenger have fastened their seat
belts.
If the driver's seat belt is not fastened after
the engine is started, an additional warning
tone will sound. The warning tone goes out
after approximately six seconds or once the
driver's seat belt is fastened.
If the driver or front passenger have not
fastened their seat belt after 6 seconds and
the doors are closed, the 7 seat belt
warning lamp lights up.
R until the driver or the front passenger have
fastened their seat belts
R if a vehicle speed of 15 mph (25 km/h) is
exceeded once, a warning tone with
increasing intensity sounds additionally for
a maximum of 60 seconds or until the driver
or front passenger have fastened their seat
belts.
If the driver or front passenger undo their seat
belts during the journey, the 7 seat belt
warning lamp lights up and the warning tone
sounds again.
Occupant safety51SafetyZ

Important safety notes
If you fail to adapt your driving style, the
driving safety systems can neither reduce the
risk of accident nor override the laws of
physics. Driving safety systems are merely
aids designed to assist driving. You are
responsible for the distance to the vehicle in
front, for vehicle speed and for braking in
good time. Always adapt your driving style to
suit the prevailing road/weather conditions,
as well as the traffic conditions and maintain
a safe distance to the vehicle in front. Drive
carefully.
i Please note that the driving safety
systems described only work as effectively
as possible when there is adequate contact
between the tires and the road surface. Pay
particular attention to the information
regarding tires, recommended minimum
tire tread depths etc. in the "Wheels and
tires" section ( Y page 310).
In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible.
ABS (Anti-lock Braking System)
Important safety notes
i Observe the "Important safety notes"
section ( Y page 59).
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
ABS works from a speed of about 5 mph
( 8 km/h) upwards, regardless of road-surface
conditions. ABS works on slippery surfaces,
even when you only brake gently.
GWARNING
If the ABS malfunctions, other driving systems
such as the BAS or the ESP ®
are also switched
off. Observe indicator and warning lamps that
may come on as well as messages in the
multifunction display that may appear.
If the ABS malfunctions, the wheels may lock
during hard braking, reducing the steering
capability and extending the braking distance.
The ! warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
Braking
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
XIf ABS intervenes: continue to depress the
brake pedal with force until the braking
situation is over.XTo make a full brake application:
depress the brake pedal with full force.
The pulsating brake pedal can be an
indication of hazardous road conditions, and
functions as a reminder to take extra care
while driving.
GWARNING
Do not pump the brake pedal. Use firm, steady
brake pedal pressure instead. Pumping the
brake pedal defeats the purpose of the ABS
and significantly reduces braking
effectiveness.
BAS (Brake Assist System)
i Observe the "Important safety notes"
section ( Y page 59).
BAS operates in emergency braking
situations. If you depress the brake pedal
quickly, BAS automatically boosts the braking
force, thus shortening the stopping distance.
XKeep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated.
Driving safety systems59SafetyZ

accident. Always pay careful attention to the
traffic situation and be ready to brake.
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.
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 59).
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.
! Vehicles without 4MATIC: switch the
ignition off when:
R the parking brake is being tested using a
dynamometer
R the vehicle is being towed with the front
axle raised
Application of the brakes by ESP ®
may
otherwise destroy the brake system.
! Vehicles with 4MATIC: switch off the
ignition when the parking brake is being
tested on a brake dynamometer.
Application of the brakes by ESP ®
may
otherwise destroy the brake system.
! Vehicles with 4MATIC: function or
performance tests may only be carried out
on a 2-axle dynamometer. If you wish to
operate the vehicle on such a
dynamometer, please consult an
authorized Mercedes-Benz Center in
advance. You could otherwise damage the
drive train or the brake system.
i Only use wheels with the recommended
tire sizes. Only then will ESP ®
function
properly.
ETS/4ETS (Electronic Traction System)GWARNING
Observe "Important safety notes"
( Y page 58).
Traction control is part of ESP ®
.
Traction control brakes the drive wheels
individually if they spin. This enables you to
pull away and accelerate on slippery surfaces,
for example if the road surface is slippery on
one side. On vehicles with 4MATIC, more
drive torque is also transferred to the wheel
or wheels with traction.
Traction control remains active if you
deactivate ESP ®
.
Driving safety systems61SafetyZ

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
GWARNING
Switch on ESP ®
immediately if one of the
previously stated conditions is no longer met.
Otherwise, ESP ®
cannot stabilize the vehicle
if it begins to lurch or when a wheel spins.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability.
R the engine's torque is no longer limited and
the drive wheels can spin. The spinning of
the wheels results in a cutting action, which
provides better grip.
R traction control is still activated.
R ESP ®
still provides support when you
brake.
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ ESP®
warning lamp in
the instrument cluster flashes. In such
situations, ESP ®
will not stabilize the vehicle.
XTo deactivate: (Y page 204).
The å ESP®
OFF warning lamp in the
instrument cluster lights up.GWARNING
When the å ESP®
OFF warning lamp is lit,
ESP ®
is deactivated.
If the ÷ ESP®
warning lamp and the
å ESP®
OFF warning lamp remain lit,
ESP ®
is not available due to a malfunction.
When ESP ®
is deactivated or not operational,
vehicle stability in standard driving
maneuvers is reduced.
Adapt your speed and driving to the prevailing
road conditions and to the non-operating
status of the ESP ®
.
! Avoid spinning the driven wheels for an
extended period with ESP ®
deactivated.
You could otherwise damage the drivetrain.
XTo activate: (Y page 204).
The å ESP®
OFF warning lamp in the
instrument cluster goes out.
Deactivating/activating ESP ®
(AMG
vehicles)
Activating/deactivating SPORT handling
mode
GWARNING
The SPORT handling mode should not be
switched on during normal driving.
Switching on the SPORT handling mode will
result in the following:
R no restriction to the engine torque
R system supported traction control is
limited
The SPORT handling mode is designed for
driving on closed tracks when the vehicle's
own natural oversteer and understeer
characteristics are desired and requires a
highly skilled and experienced driver able to
handle these critical driving situations.
You could lose control of your vehicle and
cause an accident.
Please be aware of these limits when you
switch on the SPORT handling mode.
62Driving safety systemsSafety

Do not switch on the SPORT handling when a
spare wheel is mounted.
ESP ®
is activated automatically when the
engine is started.
It may be best to activate SPORT handling
mode in the following situations:
R when using snow chains
R in deep snow
R on sand or gravelGWARNING
Switch off the SPORT handling mode and
switch on the ESP ®
immediately if the
aforementioned circumstances do not apply
anymore. Otherwise the SPORT handling
mode will only stabilize the vehicle to a limited
extent when it is starting to skid or a wheel is
spinning.
When SPORT handling mode is activated:
R ESP ®
only improves driving stability to a
limited degree.
R the engine's torque is restricted only to a
limited degree and the drive wheels can
spin. The spinning of the wheels results in
a cutting action, which provides better grip.
R traction control is still activated.
R ESP ®
still provides support when you brake
firmly.
If SPORT handling mode is activated and one
or more wheels start to spin, the ÷ ESP®
warning lamp in the instrument cluster
flashes. ESP ®
only stabilizes the vehicle to a
limited degree.
XTo activate: briefly press button :.
The M SPORT handling mode warning
lamp in the instrument cluster lights up.
The SPORT handling mode message
appears in the multifunction display.XTo deactivate: briefly press button :.
The M SPORT handling mode warning
lamp in the instrument cluster goes out.
Activating/deactivating ESP ®
GWARNING
The ESP
®
should not be switched off during
normal driving.
Disabling of the system will result in the
following:
R no restriction to engine torque
R loss of system-supported traction control
"ESP ®
OFF" is designed for driving on closed
tracks when the vehicle's natural oversteer
and understeer characteristics are desired
and requires a highly skilled and experienced
driver able to handle these critical driving
situations.
You could lose control of your vehicle and
cause an accident.
Please be aware of these limits when you
switch off the ESP ®
.
Do not switch off the ESP ®
when a 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
GWARNING
Switch on ESP ®
immediately if one of the
previously stated conditions is no longer met.
Otherwise, ESP ®
cannot stabilize the vehicle
if it begins to lurch or when a wheel spins.
Driving safety systems63SafetyZ

If you deactivate ESP®
:
R ESP ®
no longer improves driving stability.
R the engine's torque is no longer limited and
the drive wheels are able to spin. The
spinning of the wheels results in a cutting
action, which provides better grip.
R traction control is still activated.
R PRE-SAFE ®
Brake is no longer available,
nor is it activated if you brake firmly and
ESP ®
intervenes.
R ESP ®
still provides support when you brake
firmly.
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ ESP®
warning lamp in
the instrument cluster does not flash. In such
situations, ESP ®
will not stabilize the vehicle.XTo deactivate: press button : until the
å ESP®
OFF warning lamp lights up in
the instrument cluster.
The ÷ OFF message appears in the
multifunction display.GWARNING
When the å ESP®
OFF warning lamp is lit,
ESP ®
is deactivated.
If the ÷ ESP®
warning lamp and the
å ESP®
OFF warning lamp remain lit,
ESP ®
is not available due to a malfunction.
When ESP ®
is deactivated or not operational,
vehicle stability in standard driving
maneuvers is reduced.
Adapt your speed and driving to the prevailing
road conditions and to the non-operating
status of the ESP ®
.
! Avoid spinning the driven wheels for an
extended period with ESP ®
deactivated.
You could otherwise damage the drivetrain.XTo activate: briefly press button :.
The å ESP®
OFF warning lamp in the
instrument cluster goes out. The ÷ON
message appears in the multifunction
display.
EBD (electronic brake force
distribution)
i Observe the "Important safety notes"
section ( Y page 59).
EBD monitors and controls the brake
pressure on the rear wheels to improve
driving stability while braking.
GWARNING
If EBD has malfunctioned, the braking system
remains available with full brake boosting
effect. However, the rear wheels can still lock,
e.g. under full braking. This could cause you
to lose control of your vehicle and cause an
accident. You should therefore adapt your
driving style to the different handling
characteristics.
XObserve the notes on warning and indicator
lamps ( Y page 242) as well as display
messages ( Y page 216).
ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In
addition to the braking function, ADAPTIVE
BRAKE also has the HOLD function
( Y page 172) and hill start assist
( Y page 140). For further information, see
Driving tips ( Y page 156).
64Driving safety systemsSafety