2016 MERCEDES-BENZ C-Class SEDAN does not key on

regular intervals while the engine is running.
Therefore, malfunctions can be detected in
good time.
The6 restraint system warning lamp in the
instrument cluster lights up when the ignition is
switched on. It goes out no later than a few sec-
onds after the vehicle is started. The compo-
nents of the restraint system are in operational
readiness.
A malfunction has occurred if the 6restraint
system warning lamp:
Rdoes not light up after the ignition is switched
on
Rdoes not go out after a few seconds with the
engine running
Rlights up again while the engine is running
All vehicles, except hybrid vehicles:
GWARNING
If restraint system is malfunctioning, restraint
system components may be triggered unin-
tentionally or might not be triggered at all in
the event of an accident with a high rate of
vehicle deceleration. This can affect the Emer- gency Tensioning Device or air bag, for exam-
ple. This poses an increased risk of injury or
even fatal injury.
Have the restraint system checked and
repaired in a qualified specialist workshop as
soon as possible.
Hybrid vehicles:
GDANGER
If the restraint system is malfunctioning, indi- vidual restraint system components may be
triggered unintentionally or might not be trig-
gered at all in the event of an accident with a
high rate of vehicle deceleration. This could
affect Emergency Tensioning Devices or air
bags, for example. The vehicle's high-voltage
electrical system may also not be deactivated
as intended in the event of an accident. You
could suffer an electric shock if you touch the
damaged components of the vehicle's high-
voltage electrical system. This poses an
increased risk of injury or even fatal injury.
Have the restraint system checked and
repaired immediately at a qualified specialist
workshop. Immediately switch off the ignitionand remove the SmartKey from the ignition
lock after an accident.
PASSENGER AIR BAG indicator lamp
PASSENGER AIR BAG ON indicator lamp :and
PASSENGER AIR BAG OFF indicator lamp ;are
part of the Occupant Classification System
(OCS).
The indicator lamps display the status of the
front-passenger front air bag.
RPASSENGER AIR BAG ON lights up: the front-
passenger front air bag is enabled. If, in the
event of an accident, all deployment criteria
are met, the front-passenger front air bag is
deployed.
RPASSENGER AIR BAG OFF lights up: the front-
passenger front air bag is deactivated. It will
then not be deployed in the event of an acci-
dent.
Depending on the person in the front-passenger
seat, the front-passenger front air bag must
either be deactivated or enabled; see the fol-
lowing points. You must make sure of this both
before and during a journey.
RChildren in a child restraint system:
whether the front-passenger front air bag is
enabled or deactivated depends on the instal-
led child restraint system, and the age and
size of the child. Therefore, be sure to observe
the notes on the "Occupant Classification
System (OCS)" (
Ypage 54) and on "Chil-
dren in the vehicle" (Ypage 62). There you
will also find instructions on rearward and
forward-facing child restraint systems on the
front-passenger seat.
RAll other persons: depending on the classi-
fication of the person in the front-passenger
Occupant safety47
Safety
Z

Window curtain air bags
Window curtain air bags:are integrated into
the side of the roof frame and deployed in the
area from the A-pillar to the C-pillar.
When deployed, the window curtain air bag
enhances the level of protection for the head.
However, it does not protect the chest or arms.
In the event of a side impact, the window curtain
air bag is deployed on the side on which the
impact occurs.
If the system determines that they can offer
additional protection to that provided by the
seat belt, a window curtain air bag may be
deployed in other accident situations
(
Ypage 58).
Occupant Classification System
(OCS)
Introduction
The Occupant Classification System (OCS) cat-
egorizes the person in the front-passenger seat.
Depending on that result, the front-passenger
front air bag is either enabled or deactivated.
The system does not disable:
Rthe side impact air bag
Rthe window curtain air bag
Rthe Emergency Tensioning Devices
Prerequisites
To be classified correctly, the front passenger
must sit:
Rwith the seat belt fastened correctly
Rin an almost upright position with their back
against the seat backrest
Rwith their feet resting on the floor, if possible If the front passenger does not observe these
conditions, OCS may produce a false classifica-
tion, e.g. because the front passenger:
Rtransfers their weight by supporting them-
selves on a vehicle armrest
Rsits in such a way that their weight is raised
from the seat cushion
If it is absolutely necessary to install a child
restraint system on the front-passenger seat, be
sure to observe the correct positioning of the
child restraint system. Never place objects
under or behind the child restraint system, e.g.
cushions. Fully retract the seat cushion length.
The entire base of the child restraint system
must always rest on the seat cushion of the
front-passenger seat. The backrest of the
forward-facing child restraint system must lie as
flat as possible against the backrest of the front-
passenger seat.
The child restraint system must not touch the
roof or be subjected to a load by the head
restraint. Adjust the angle of the seat backrest
and the head restraint position accordingly.
Only then can OCS be guaranteed to function
correctly. Always observe the child restraint sys-
tem manufacturer's installation instructions.
Occupant Classification System opera-
tion (OCS)
:PASSENGER AIR BAG ON indicator lamp
;PASSENGER AIR BAG OFF indicator lamp
The indicator lamps inform you whether the
front-passenger front air bag is deactivated or
enabled.
XPress the Start/Stop button once or twice, or
turn the SmartKey to position 1or 2in the
ignition lock.
The system carries out self-diagnostics.
54Occupant safety
Safety

SmartKey battery
Important safety notes
GWARNING
Batteries contain toxic and corrosive substan- ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatalinjury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention immediately.
HEnvironmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separatelyand recycled to protect the
environment.
Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe-
cialist workshop or a special
collection point for used bat-
teries.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National guide-
lines must be observed during disposal. In Cal-
ifornia, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/index.cfm .
Mercedes-Benz recommends that you have the
batteries replaced at a qualified specialist work-
shop.
Checking the battery
XPress the &or% button.
The battery is working properly if battery
check lamp :lights up briefly.
The battery is discharged if battery check
lamp :does not light up briefly.
XChange the battery (Ypage 84).
If the SmartKey battery is checked within the
signal reception range of the vehicle, pressing
the & or% button:
Rlocks or
Runlocks the vehicle
iYou can get a battery at any qualified spe-
cialist workshop.
Replacing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the SmartKey
(Ypage 83).
XPress mechanical key ;into the SmartKey
opening in the direction of the arrow until bat-
tery compartment cover :opens. Do not
hold battery compartment cover :closed
while doing so.
XRemove battery compartment cover :.
84SmartKey
Opening and closing

Problems with the SmartKey
ProblemPossible causes/consequences andMSolutions
You can no longer lock or
unlock the vehicle using
the SmartKey.The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 84) and replace it if necessary
(Ypage 84).
If this does not work:
XUnlock (Ypage 89) or lock (Ypage 89) the vehicle using the
mechanical key.
There is interference from a powerful source of radio waves.
XUnlock (Ypage 89) or lock (Ypage 89) the vehicle using the
mechanical key.
The SmartKey is faulty.
XUnlock (Ypage 89) or lock (Ypage 89) the vehicle using the
mechanical key.
XHave the SmartKey checked at a qualified specialist workshop.
You can no longer lock or
unlock the vehicle using
KEYLESS-GO.KEYLESS-GO was deactivated.
XReactivate KEYLESS-GO (Ypage 82).
The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 84) and replace it if necessary
(Ypage 84).
If this does not work:
XUnlock (Ypage 89) or lock (Ypage 89) the vehicle using the
mechanical key.
There is interference from a powerful source of radio waves.
XUnlock (Ypage 89) or lock (Ypage 89) the vehicle using the
mechanical key.
KEYLESS-GO is malfunctioning.
XLock/unlock the vehicle using the remote control function of the
SmartKey.
XHave the vehicle and SmartKey checked at a qualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function:
XUnlock (Ypage 89) or lock (Ypage 89) the vehicle using the
mechanical key.
XHave the vehicle and SmartKey checked at a qualified specialist
workshop.
86SmartKey
Opening and closing

ProblemPossible causes/consequences andMSolutions
The engine cannot be
started using the Smart-
Key.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 (Ypage 350).
or
XJump-start the vehicle (Ypage 352).
or
XConsult a qualified specialist workshop.
The engine cannot be
started using the Start/
Stop button. The Smart-
Key is in the vehicle.The vehicle is locked.
XUnlock the vehicle and try to start the vehicle again.
The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 84) and replace it if necessary
(Ypage 84).
If this does not work:
XStart your vehicle with the SmartKey in the ignition lock.
There is interference from a powerful source of radio waves.
XStart your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-
Key.XHave the SmartKey deactivated at a qualified specialist workshop.
XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
You have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
Doors
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
Doors87
Opening and closing
Z

especially if the vehicle is in motion. There is a
risk of poisoning.
Always switch off the engine before opening
the trunk lid. Never drive with the trunk lid
open.
GWARNING
If objects, luggage or loads are not secured or
not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle
occupants. There is a risk of injury, particu-
larly in the event of sudden braking or a sud-
den change in direction.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey.
!The trunk lid swings upwards when opened.
Therefore, make sure that there is sufficient
clearance above the trunk lid.
The opening dimensions of the trunk lid can be
found in the "Vehicle data" section
(
Ypage 394).
You can limit the opening angle of the trunk lid in
COMAND or Audio 20 (see the Digital Opera-
tor's Manual).
Do not leave the SmartKey in the trunk. You
could otherwise lock yourself out.
You should preferably place luggage or loads in
the trunk. Observe the loading guidelines
(
Ypage 308).
Obstruction recognition with trunk lid
reversing feature
Vehicles with trunk lid remote closing fea-
ture:
The trunk lid is equipped with automatic
obstruction detection with a reversing feature. If
a solid object blocks or restricts the trunk lid
when automatically opening, this procedure is
stopped. If a solid object blocks or restricts the
trunk lid when automatically closing, the trunk
lid opens again automatically. The automatic
obstruction detection with reversing feature is
only an aid. It is not a substitute for your atten-
tiveness when opening and closing the trunk lid.
GWARNING
The reversing feature does not react:
Rto soft, light and thin objects, e.g. small fin-
gers
Rover the last 1/3 in (8 mm) of the closing
movement
This means that the reversing feature cannot
prevent someone being trapped in these sit-
uations. There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure.
If somebody becomes trapped:
Rpress the Fbutton on the SmartKey, or
Rpull or press the remote operating switch
on the driver's door or
Rpress the closing or locking button on the
trunk lid, or
Rpull on the trunk lid handle
Vehicles with HANDS-FREE ACCESS:
It is also possible to stop the closing process by
performing a kicking movement under the rear
bumper.
Opening and closing manually
Opening
XPress the Fbutton on the SmartKey.
or
XPull handle :.
The trunk lid opens.
90Trunk
Opening and closing

Vehicles with trunk lid remote closing fea-
ture and KEYLESS-GO:when the driver's door
is closed you can simultaneously close the trunk
lid and lock the vehicle. The KEYLESS-GO key
must be in the rear detection range of the vehi-
cle.
XPress locking button ;in the trunk lid.
If KEYLESS-GO detects a SmartKey outside
the vehicle, the trunk lid closes. The vehicle is locked.
If KEYLESS-GO detects a SmartKey in the trunk,
the trunk lid opens again after it is closed.
If KEYLESS-GO detects a second SmartKey out-
side the vehicle, the trunk lid remains closed.
If KEYLESS-GO detects a SmartKey in the trunk
before the closing procedure starts, the trunk lid
remains open.
HANDS-FREE ACCESS
Important safety notes
GWARNING
The vehicle's exhaust system may be very hot. You could burn yourself by touching the
exhaust system if you use HANDS-FREE
ACCESS. There is a risk of injury. Always
ensure that you only make the kicking move-
ment within the detection range of sensors.
!If the SmartKey is within the rear detection
range of KEYLESS-GO, the following situa-
tions, for example, could lead to the uninten-
tional opening of the trunk:
Rusing a car wash
Rusing a power washer
Make sure that the SmartKey is at least 10 ft
(3 m) away from the vehicle.
General notes
With KEYLESS-GO and HANDS-FREE ACCESS,
you can open or close the trunk lid or stop the
procedure without using your hands. This is use- ful if you have your hands full. To do this, make
a kicking movement under the bumper with your
foot. Observe the following points:
RCarry your KEYLESS-GO key about your per-
son. The KEYLESS-GO key must be in the rear
detection range of the vehicle.
RWhen making the kicking movement, make
sure that you are standing firmly on the
ground and that there is sufficient clearance
to the rear of the vehicle. You could otherwise
lose your balance e.g. on ice.
RAlways ensure that you only make the kicking
movement within the detection range of sen-
sors
:.
RStand at least 12 in (30 cm) away from the
rear area while doing so.
RDo not come into contact with the bumper
while making the kicking movement. Other-
wise, the sensors may not function correctly.
RHANDS-FREE ACCESS does not function
when the engine is started.
RDirt caused by road salt around sensors :
may restrict functionality.
Using the HANDS-FREE ACCESS with a pros-
thetic leg may restrict functionality.
RIf a KEYLESS-GO key is within the rear detec-
tion range of KEYLESS-GO, HANDS-FREE
ACCESS could be triggered. The trunk lid
could thus be opened or closed unintention-
ally, for example, if you:
-sit on the edge of the trunk.
-set something down or lift something up
behind the vehicle.
-polish the rear of the vehicle.
Do not carry the KEYLESS-GO key about your
person in these situations or in situations sim-
ilar to these. This will prevent the uninten-
tional opening/closing of the trunk.
92Trunk
Opening and closing

Operation
XTo open/close:kick into sensor detection
range :under the bumper with your foot.
A warning tone will sound while the trunk lid is
opening or closing.
XIf the trunk lid does not open/close after
several attempts: wait at least ten seconds
and then using your foot kick under the
bumper again.
If you hold your foot under the bumper for too
long, the trunk lid does not open or close.
Repeat the leg movement more quickly if this
occurs.
To stop the opening or closing procedure:
Rkick with your leg in the sensor detection
range :under the bumper or
Rpress the closing button on the trunk lid, or
Rpull the handle on the outside of the trunk lid
or
Rpress the Fbutton on the SmartKey
If the trunk lid closing procedure has been stop-
ped:
Rmove your foot under the bumper again and
the trunk lid will open
If the trunk lid opening procedure has been
stopped:
Rmove your foot under the bumper again and
the trunk lid will close
Opening/closing automatically from
inside
Important safety notes
GWARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Exhaust
gases can enter the vehicle interior if the
trunk lid is open when the engine is running,
especially if the vehicle is in motion. There is a
risk of poisoning.
Always switch off the engine before opening
the trunk lid. Never drive with the trunk lid
open.
GWARNING
Parts of the body could become trapped dur-
ing automatic closing of the trunk lid. More-
over, people, e.g. children, may be standing in the closing area or may enter the closing area
during the closing process. There is a risk of
injury.
Make sure that nobody is in the vicinity of the
closing area during the closing process.
Use one of the following options to stop the
closing process:
Rpress the Fbutton on the SmartKey.
Rpull or press the remote operating switch
on the driver's door.
Rpress the closing or locking button on the
trunk lid.
Rpull the trunk lid handle
Vehicles with HANDS-FREE ACCESS:
It is also possible to stop the closing process by
performing a kicking movement under the rear
bumper.
!The trunk lid swings upwards when opened.
Therefore, make sure that there is sufficient
clearance above the trunk lid.
The opening dimensions of the trunk lid can be
found in the "Vehicle data" section
(
Ypage 394).
Trunk93
Opening and closing
Z