2016 MERCEDES-BENZ C CLASS warning lights

regular intervals while the engine is running.
Therefore, malfunctions can be detected in
good time.
The u 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 u restraint
system warning lamp: R
does not light up after the ignition is switched
on R
does not go out after a few seconds with the
engine running R
lights up again while the engine is running
All vehicles, except hybrid vehicles:
G WARNING
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:
G DANGER
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 ignition
and remove the SmartKey from the ignition
lock after an accident.
PASSENGER AIR BAG indicator lamp
PASSENGER AIR BAG ON indicator lamp C and
PASSENGER AIR BAG OFF indicator lamp D are
part of the Occupant Classification System
(OCS).
The indicator lamps display the status of the
front-passenger front air bag. R
PASSENGER 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. R
PASSENGER 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. R
Children 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)" ( Y
page 54) and on "Chil-
dren in the vehicle" ( Y
page 62). There you
will also find instructions on rearward and
forward-facing child restraint systems on the
front-passenger seat. R
All other persons: depending on the classi-
fication of the person in the front-passengerOccupant safety 47
Safety Z

X
Press the release button in the belt buckle,
hold the belt tongue firmly and guide the belt
back.
Seat belt adjustment The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. This func-
tion adjusts the driver's and front-passenger
seat belt to the upper body of the occupants.
The belt strap is tightened slightly when: R
the belt tongue is engaged in the buckle and R
the ignition is switched on
The seat-belt adjustment will apply a certain
retraction force if any slack is detected between
the vehicle occupant and the seat belt. Do not
hold on to the seat belt tightly while it is adjust-
ing.
You can switch the seat-belt adjustment on and
off using the multimedia system. Information on
activating and deactivating the seat-belt adjust-
ment function can be found in the Digital Oper-
ator's Manual or in the separate operating
instructions for the multimedia system.
Belt warning for the driver and front
passenger The v seat belt warning lamp in the instru-
ment cluster is a reminder that all vehicle occu-
pants must wear their seat belts. It may light up
continuously or flash. In addition, there may be
a warning tone.
Regardless of whether the driver's seat belt has
already been fastened, the v seat belt warn-
ing lamp lights up for six seconds each time the
engine is started. If the front doors are closed
and the driver or front-passenger seat belt has
not been fastened, the v seat belt warning
lamp lights up again after the six seconds. As
soon as the driver's and front-passenger seat
belts are fastened or a front door is opened
again, the v seat belt warning lamp goes out.
If the driver's seat belt is not fastened after the
engine is started, an additional warning tone will
sound. The warning tone switches off after six
seconds or once the driver's seat belt is fas-
tened.
If the vehicle speed exceeds 15 mph (25 km/ h)
an d the driver's or front-passenger seat belt is
not fastened, a warning tone sounds again. The
warning tone sounds with increasing intensity
for a maximum of 60 seconds or until the driver or front passenger have fastened their seat
belts.
If the driver or front passenger unfasten their
seat belt while the vehicle is in motion, the belt
warning automatically reactivates.
i For more information on the v seat belt
warning lamp, see "Warning and indicator
lamps in the instrument cluster, seat belts"
( Y
page 287).
Air bags
Introduction The air bag installation point is identified by the
label AIR BAG.
An air bag supplements a correctly fastened
seat belt. However, it is not intended as a sub-
stitute for the seat belt. Air bags provide addi-
tional protection in the event of an accident.
Not all air bags are deployed in an accident. The
various air bag systems work independently of
each other ( Y
page 58).
There is, however, no system available today
that can completely rule out injury or death.
It is also not possible to rule out a risk of injury
caused by an air bag due to the high speed at
which the air bag must be deployed.
Important safety notes
G WARNING
If you do not sit in the correct seat position,
the air bag cannot protect as intended and
could even cause additional injury when
deployed. This poses an increased risk of
injury or even fatal injury.
To avoid hazardous situations, always make
sure that all of the vehicle's occupants: R
have fastened their seat belts correctly,
including pregnant women R
are sitting correctly and maintain the great-
est possible distance to the air bags R
follow the following instructions
Always make sure that there are no objects
between the air bag and the vehicle's occu-
pants.Occupant safety 51
Safety Z

The PASSENGER AIR BAG OFF and PASSENGER
AIR BAG ON indicator lamps must light up simul-
taneously for approximately six seconds.
The indicator lamps display the status of the
front-passenger front air bag. R
PASSENGER 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. R
PASSENGER 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.
If the status of the front-passenger front air bag
changes while the vehicle is in motion, an air bag
display message appears in the instrument clus-
ter ( Y
page 265). When the front-passenger
seat is occupied, always pay attention to the
PASSENGER AIR BAG ON and PASSENGER AIR
BAG OFF indicator lamps. Be aware of the status
of the front-passenger front air bag both before
and during the journey.
G WARNING
If the PASSENGER AIR BAG OFF indicator
lamp is lit, the front-passenger front air bag is
disabled. It will not be deployed in the event of
an accident and cannot perform its intended
protective function. A person in the front-
passenger seat could then, for example, come
into contact with the vehicle's interior, espe-
cially if the person is sitting too close to the
dashboard. This poses an increased risk of
injury or even fatal injury.
When the front-passenger seat is occupied,
always ensure that: R
the classification of the person in the front-
passenger seat is correct and the front-
passenger front air bag is enabled or disa-
bled in accordance with the person in the
front-passenger seat R
the front-passenger seat has been moved
back as far back as possible. R
the person is seated correctly.
Make sure, both before and during the jour-
ney, that the status of the front-passenger
front air bag is correct. G WARNING
If you secure a child in a rearward-facing child
restraint system on the front-passenger seat
and the PASSENGER AIR BAG ON indicator
lamp is lit up, the front-passenger front air bag
may deploy in an accident. The child could be
struck by the air bag. This poses an increased
risk of injury or even fatal injury.
Make sure that the front-passenger front air
bag has been disabled. The PASSENGER AIR
BAG OFF indicator lamp must be lit.
If the PASSENGER AIR BAG OFF indicator lamp
remains off and/or the PASSENGER AIR BAG
ON indicator lamp lights up, do not install a rear-
ward-facing child restraint system on the front-
passenger seat. You can find more information
on OCS under "Problems with the Occupant
Classification System" ( Y
page 58).
G WARNING
If you secure a child in a forward-facing child
restraint system on the front-passenger seat
and you position the front-passenger seat too
close to the dashboard, in the event of an
accident, the child could: R
come into contact with the vehicle's inte-
rior if the PASSENGER AIR BAG OFF indi-
cator lamp is lit, for example R
be struck by the air bag if the PASSENGER
AIR BAG ON is lit up
This poses an increased risk of injury or even
fatal injury.
Always move the front-passenger seat as far
back as possible and fully retract the seat
cushion length. Always make sure that the
shoulder belt strap is correctly routed from
the vehicle belt sash guide to the shoulder
belt guide on the child restraint system. The
shoulder belt strap must be routed forwards
and downwards from the vehicle belt sash
guide. If necessary, adjust the vehicle belt
sash guide and the front-passenger seat
accordingly. Always observe the child
restraint system manufacturer's installation
instructions.Occupant safety 55
Safety Z

If OCS determines that: R
the front-passenger seat is unoccupied, the
PASSENGER AIR BAG OFF indicator lamp
lights up after the system self-test and
remains lit. This indicates that the front-
passenger front air bag is deactivated. R
the front-passenger seat is occupied by a
child of up to twelve months old, in a standard
child restraint system, the PASSENGER AIR
BAG OFF indicator lamp lights up after the
system self-test and remains lit. This indi-
cates that the front-passenger front air bag is
deactivated.
But even in the case of a twelve-month-old
child, in a standard child restraint system, the
PASSENGER AIR BAG ON can light up perma-
nently after the system self-test. This indi-
cates that the front-passenger front air bag is
activated. The result of the classification is
dependent on, among other factors, the child
restraint system and the child's stature. It is
recommended that you install the child
restraint system on a suitable rear seat. R
The front-passenger seat is occupied by a
person of smaller stature (e.g. a teenager or
small adult), either the PASSENGER AIR BAG
ON or PASSENGER AIR BAG OFF indicator
lamp lights up and remains lit after the system
self-test depending on the result of the clas-
sification. -
If the PASSENGER AIR BAG ON indicator
lamp lights up, move the front-passenger
seat as far back as possible. Alternatively, a
person of smaller stature can sit on a rear
seat. -
If the PASSENGER AIR BAG OFF indicator
lamp is lit, a person of smaller stature
should not use the front-passenger seat. R
the front-passenger seat is occupied by an
adult or a person of adult stature, the
PASSENGER AIR BAG ON indicator lamp
lights up after the system self-test and
remains lit. This indicates that the front-
passenger front air bag is activated.
If children are traveling in the vehicle, be sure to
observe the notes on "Children in the vehicle"
( Y
page 62).
When OCS is malfunctioning, the red u
restraint system warning lamp in the instrument
cluster and the PASSENGER AIR BAG OFF indi-
cator lamp light up simultaneously. The front-
passenger front air bag is deactivated in this
case and does not deploy du ri
ng an accident. Have the system checked by qualified techni-
cians as soon as possible. Consult an authorized
Mercedes-Benz Center. The front-passenger
seat should only be repaired at an authorized
Mercedes-Benz Center.
If the front-passenger seat, the seat cover or the
seat cushion is damaged, have the necessary
repair work carried out at an authorized
Mercedes-Benz Center.
For safety reasons, Mercedes-Benz recom-
mends that you only use seat accessories that
have been approved by Mercedes-Benz.
If the driver's air bag deploys, this does not
mean that the front-passenger front air bag will
also deploy. The Occupant Classification Sys-
tem (OCS) categorizes the occupant in the front-
passenger seat. Depending on that result, the
front-passenger front air bag is either enabled or
deactivated.
System self-test
G DANGER
If both the PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps do
not light up during the system self-test, the
system is malfunctioning. The front-
passenger front air bag might be triggered
unintentionally or might not be triggered at all
in the event of an accident with high deceler-
ation. This poses an increased risk of injury or
even fatal injury.
In this case the front-passenger seat may not
be used. Do not install a child restraint system
on the front-passenger seat. Have the Occu-
pant Classification System (OCS) checked
and repaired immediately at a qualified spe-
cialist workshop.
G DANGER
If the PASSENGER AIR BAG OFF indicator
lamp remains lit after the system self-test, the
front-passenger front air bag is disabled. It will
not be deployed in the event of an accident. In
this case, the front-passenger front air bag
cannot perform its intended protective func-
tion, e.g. when a person is seated in the front-
passenger seat.56
Occupant safety
Safety

Problems with the Occupant Classification System (OCS) Be sure to observe the notes on "System self-test" ( Y
page 56).
Problem
Possible causes/consequences and P Solutions
The PASSENGER AIR
BAG OFF indicator lamp
lights up and remains lit,
even though the front-
passenger seat is occu-
pied by an adult or a per-
son of a stature corre-
sponding to that of an
adult. The classification of the person on the front-passenger seat is incor-
rect. X
Make sure the conditions for a correct classification of the person
on the front-passenger seat are met ( Y
page 54).X
If the PASSENGER AIR BAG OFF indicator lamp remains lit, the front-
passenger seat may not be used. X
Have OCS checked as soon as possible at an authorized Mercedes-
Benz Center.
The PASSENGER AIR
BAG OFF indicator lamp
does not light up and/or
does not stay on.
The front-passenger seat
is: R
unoccupied R
occupied with the
weight of a child up to
twelve months old in a
child restraint system OCS is malfunctioning. X
Make sure there is nothing between the seat cushion and the child
seat. X
Make sure that the entire base of the child restraint system rests 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. If necessary,
adjust the position of the front-passenger seat. X
Make sure that the seat cushion length is fully retracted. X
When installing the child restraint system, make sure that the seat
belt is tight. Do not pull the seat belt tight using the front-passenger
seat adjustment. This could result in the seat belt and the child
restraint system being pulled too tightly. X
Check for correct installation of the child restraint system.
Make sure that the head restraint does not apply a load to the child
restraint system. If necessary, adjust the head restraint accord-
ingly. X
Make sure that no objects are applying additional weight onto the
seat. X
If the PASSENGER AIR BAG OFF indicator lamp remains off and/or
the PASSENGER AIR BAG ON indicator lamp lights up, do not install
a child restraint system on the front-passenger seat. It is recom-
mended that you install the child restraint system on a suitable rear
seat. X
Have OCS checked as soon as possible at an authorized Mercedes-
Benz Center.
Deployment of Emergency Tensioning
Devices and air bags
Important safety notes
G WARNING
The air bag parts are hot after an air bag has
been deployed. There is a risk of injury. Do not touch the air bag parts. Have a
deployed air bag replaced at a qualified spe-
cialist workshop as soon as possible.
G WARNING
A deployed air bag no longer offers any pro-
tection and cannot provide the intended pro-58
Occupant safety
Safety

Important safety notes If you fail to adapt your driving style or if you are
inattentive, th e driving safet y systems can nei-
ther reduce th e ris k of an acciden t no r override
th e laws of physics . Drivin g safet y systems are
merely aids designed to assist driving . You are
responsible for maintainin g th e distanc e to th e
vehicl e in front, for vehicl e speed, for braking in
goo d time, and for staying in lane. Always adapt
your driving style to suit th e prevailing road and
weather condition s and maintai n a saf e distanc e
from th e vehicl e in front. Drive carefully.
The driving safet y systems describe d only wor k
as effectivel y as possible when there is ade-
quat e contact between th e tires and th e road
surface. Pay particular attention to th e informa-
tion regarding tires , recommended minimum
tire tread depths etc. in th e "Wheels and tires "
section ( Y
page 360).
In wintr y driving conditions, always use winte r
tires (M+ S tires )a nd 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)
General information 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.
The % ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
ABS works from a speed of about 5 mph
(8 km/h), regardless of road-surface conditions.
ABS works on slippery surfaces, even when you
only brake gently.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 68).
G WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac- tivated. There is an increased danger of skid-
ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp ( Y
page 289) and dis-
play messages which may be shown in the
instrument cluster ( Y
page 256).
Braking X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking sit-
uation is over. X
To make a full brake application: depress
the brake pedal with full force.
If ABS intervenes when braking, you will feel a
pulsing in the brake pedal.
The pulsating brake pedal can be an indication
of hazardous road conditions, and functions as a
reminder to take extra care while driving.
BAS (Brake Assist System)
General information BAS operates in emergency braking situations.
If you depress the brake pedal quickly, BAS
automatically boosts the braking force, thus
shortening the stopping distance.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 68).
G WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.68
Driving safety systems
Safety

G WARNING
If you deactivate ESP ®
, ESP ®
no longer sta-
bilizes the vehicle. There is an increased risk
of skidding and an accident.
Only deactivate ESP ®
in the situations descri-
bed in the following.
! Avoid spinning the driven wheels for an
extended period with ESP ®
deactivated. You
could otherwise damage the drivetrain.
In the following situations, it may be better to
activate SPORT handling mode or deactivate
ESP ®
: R
when using snow chains R
in deep snow R
on sand or gravel R
on specially designated roads when the vehi-
cle's own oversteering and understeering
characteristics are desired
Driving in SPORT handling mode or without
ESP ®
requires an extremely qualified and expe-
rienced driver.
i Activate ESP ®
as soon as the situations
described above no longer apply. ESP ®
will
otherwise not be able to stabilize the vehicle if
the vehicle starts to skid or a wheel starts to
spin.
Deactivating/activating ESP ®
X
To activate SPORT handling mode: briefly
press button C .
The t SPORT handling mode warning
lamp in the instrument cluster lights up. The SPORT handling mode
message appears in
the multifunction display. X
To deactivate SPORT handling mode:
briefly press button C .
The t SPORT handling mode warning
lamp in the instrument cluster goes out. X
To deactivate ESP ®
: press button C until
the

SmartKey battery
Important safety notes
G WARNING
Batteries contain toxic and corrosive substan-
ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatal
injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
H Environmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately
and 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 X
Press the 7 or 6 button.
The battery is working properly if battery
check lamp C lights up briefly.
The battery is discharged if battery check
lamp C does not light up briefly. X
Change the battery ( Y
page 84).
If the SmartKey battery is checked within the
signal reception range of the vehicle, pressing
the 7 or 6 button: R
locks or R
unlocks the vehicle
i You can get a battery at any qualified spe-
cialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery. X
Take the mechanical key out of the SmartKey
( Y
page 83).
X
Press mechanical key D into the SmartKey
opening in the direction of the arrow until bat-
tery compartment cover C opens. Do not
hold battery compartment cover C closed
while doing so. X
Remove battery compartment cover C .84
SmartKey
Opening and closing