warning lights MERCEDES-BENZ S CLASS 2017 User Guide

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 51).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-
tection in an accident. There is an increased
risk of injury.
Have the vehicle towed to a qualified special-
ist workshop in order to have a deployed air
bag replaced.
It is important for your safety and that of your
passenger to have deployed air bags replacedOccupant safety 55
Safety Z

and to have any malfunctioning air bags
repaired. This will help to make sure the air bags
continue to perform their protective function for
the vehicle occupants in the event of a crash.
G WARNING
Emergency Tensioning Devices that have
deployed pyrotechnically are no longer opera-
tional and are unable to perform their inten-
ded protective function. This poses an
increased risk of injury or even fatal injury.
Have pyrotechnically triggered Emergency
Tensioning Devices replaced immediately at a
qualified specialist workshop.
An electric motor is used by PRE-SAFE ®
to trig-
ger the tightening of the seat belt in hazardous
situations. This procedure is reversible.
If Emergency Tensioning Devices are triggered
or air bags are deployed, you will hear a bang,
and a small amount of powder may also be
released. The u restraint system warning
lamp lights up.
Only in rare cases will the bang affect your hear-
ing. The powder that is released generally does
not constitute a health hazard, but it may cause
short-term breathing difficulties in people with
asthma or other respiratory problems. Provided
it is safe to do so, you should leave the vehicle
immediately or open the window in order to pre-
vent breathing difficulties.
Air bags and pyrotechnic Emergency Tensioning
Devices (ETDs) contain perchlorate material,
which may require special handling and regard
for the environment. National guidelines must
be observed during disposal. In California, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm .
Method of operation During the first stage of a collision, the restraint
system control unit evaluates important physi-
cal data relating to vehicle deceleration or accel-
eration, such as: R
duration R
direction R
intensity
Based on the evaluation of this data, the
restraint system control unit triggers the Emer-
gency Tensioning Devices during a frontal or
rear collision. An Emergency Tensioning Device can only be
triggered, if: R
the ignition is switched on R
the components of the restraint system are
operational. You can find further information
under: "Restraint system warning lamp"
( Y
page 43) R
the belt tongue is engaged in the buckle on
the respective front-passenger seat
The Emergency Tensioning Devices in the rear
compartment are triggered independently of the
lock status of the seat belts.
Vehicles with belt bags: the belt bags are also
deployed depending on the type and severity of
the accident.
Vehicles with a rear reclining seat: the Emer-
gency Tensioning Device is only triggered if the
belt buckle tongue is engaged in the belt buckle.
If the seat backrest is reclined, the cushion air
bag will also be deployed depending on the type
and severity of the accident.
If the restraint system control unit detects a
more severe accident, further components of
t h e restraint system are activated independ-
ently of each other in certain frontal collision
situations: R
Front air bags and driver's knee bag R
Window curtain air bag, if the system deter-
mines that deployment can offer additional
protection to that provided by the seat belt
The front-passenger front air bag is activated or
deactivated depending on the person on the
front-passenger seat. The front-passenger front
air bag can only deploy in an accident if the
PASSENGER AIR BAG OFF indicator lamp is off.
Observe the information on the PASSENGER AIR
BAG indicator lamps ( Y
page 43).
Your vehicle has two-stage front air bags. During
the first deployment stage, the front air bag is
filled with propellant gas to reduce the risk of
injuries. The front air bag is fully deployed with
the maximum amount of propellant gas if a sec-
ond deployment threshold is reached within a
few milliseconds.
The activation threshold of the Emergency Ten-
sioning Devices and the air bag are determined
by evaluating the rate of vehicle deceleration or
acceleration which occurs at various points in
the vehicle. This process is pre-emptive in
nature. Deployment should take place in good
time at the start of the collision.56
Occupant safety
Safety

R
ESP ®
( E lectronic S tability P rogram)
( Y
page 71)R
EBD ( E lectronic B rake force D istribution)
( Y
page 73)R
ADAPTIVE BRAKE ( Y
page 73)R
PRE-SAFE ®
Brake ( Y
page 73)R
STEER CONTROL ( Y
page 75)
Important safety notes If you fail to adapt your driving style or if you are
inattentive, the driving safety systems can nei-
ther reduce the risk of an accident nor override
the laws of physics. Driving safety systems are
merely aids designed to assist driving. You are
responsible for maintaining the distance to the
vehicle in front, for vehicle speed, for braking in
good time, and for staying in lane. Always adapt
your driving style to suit the prevailing road and
weather conditions and maintain a safe distance
from the vehicle in front. Drive carefully.
The driving safety systems described only work
as effectively as possible when there is ade-
quate contact between the tires and the road
surface. Pay particular attention to the informa-
tion regarding tires, recommended minimum
tire tread depths etc. in the "Wheels and tires"
section ( Y
page 343).
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)
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 66).
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 261) and dis-
play messages which may be shown in the
instrument cluster ( Y
page 228).
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 66).66
Driving safet y system s
Sa fety

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 80).
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 obtain a battery from any qualified
specialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery. X
Take the mechanical key out of the SmartKey
( Y
page 79).
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 .80
SmartKey
Opening and closing

! Do not move the front-passenger seat fully
forwards if there are objects in the parcel net
in the front-passenger footwell. The objects
could otherwise be damaged.
Adjusting the front-passenger seat
The power supply or the ignition must be
switched on so that the front-passenger seat
can be selected ( Y
page 146).X
To select the front-passenger seat: press
button C repeatedly until the indicator lamp
in the button lights up.
When the indicator lamp in button C lights up,
for the front-passenger seat you can adjust: R
adjust the seat ( Y
page 101)R
seat heating ( Y
page 112)R
seat ventilation ( Y
page 113)R
the memory function to call up or save set-
tings ( Y
page 120).
Adjusting the front-passenger seat
from the rear
Important safety notes
G WARNING
Children could become trapped if they adjust
the seats, particularly when unattended.
There is a risk of injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
The seats can still be adjusted when the power
supply is switched off. G WARNING
When you adjust a seat, you or other vehicle
occupants could become trapped, e.g. on the
seat guide rail. There is a risk of injury.
Make sure when adjusting a seat that no one
has any body parts in the sweep of the seat.
Observe the safety notes on "Air bags"
( Y
page 48) and "Children in the vehicle"
( Y
page 59).
G WARNING
The front-air bags for could also injure the
vehicle occupants in the front If the front
seats are positioned too close to the dash-
board or steering wheel. This poses an
increased risk of injury or even fatal injury.
Always adjust the front seats so that they are
as far from the front air bags as possible. Also
observe the notes on the correct adjustment
of the seats.
! Do not move the front-passenger seat fully
forwards if there are objects in the parcel net
in the front-passenger footwell. The objects
could otherwise be damaged.
i You can use the rear-compartment override
button to disable the setting of the front-
passenger seat from the rear ( Y
page 65).
Adjusting the rear seat
C
Selects rear-compartment seat
D
Head restraint height

Exterior lighting
General notes USA only: if you wish to drive during the daytime
without lights, switch off the Daytime Run‐
ning Lights function via the on-board com-
puter ( Y
page 225).
Setting the exterior lighting
Setting options Exterior lighting can be set using: R
the light switch ( Y
page 124)R
the combination switch ( Y
page 125)R
the on-board computer ( Y
page 225)
Light switch Operation
G c
Left-hand standing lampsH d
Right-hand standing lampsI `
Parking lamps, license plate and
instrument cluster lightingJ X
Automatic headlamp mode, controlled
by the light sensor
K X
Low-beam/high-beam headlamps
If you hear a warning tone when you leave the
vehicle, the lights may still be switched on. X
Turn the light switch to the X position.
The exterior lighting (except the parking/stand-
ing lamps) switches off automatically if you: R
remove the SmartKey from the ignition lock R
open the driver's door with the SmartKey in
position 0 in the ignition lock Automatic headlamp mode
G WARNING
When the light switch is set to X , the low-
beam headlamps may not be switched on
automatically if there is fog, snow or other
causes of poor visibility due to the weather
conditions such as spray. There is a risk of an
accident.
In such situations, turn the light switch to
X .
The automatic headlamp feature is only an aid.
The driver is responsible for the vehicle's light-
ing at all times.
X is the favored light switch setting.
The light setting is automatically selected
according to the brightness of the ambient light,
but not in the event of poor visibility due to
weather conditions such as fog, snow or spray. R
With the SmartKey in position 1 in the ignition
lock, the parking lamps are switched on or off
automatically depending on the brightness of
the ambient light. R
USA only: if you have switched on the Day‐
time Running Lights function via the on-
board computer, and the engine is running,
the daytime running lamps or the parking
lamps and low-beam headlamps are switched
on or off automatically depending on the
ambient light. R
Canada only: depending on the ambient light,
the daytime running lamps or the parking and
low-beam headlamps are switched on/off
automatically when the engine is running. X
To switch on the automatic headlamps:
turn the light switch to the X position.
USA only: The daytime running lamps improve
the visibility of your vehicle during the day. Here,
the Daytime Running Lights function must
be switched on via the on-board computer
( Y
page 225).
If the engine is running and you turn the light
switch to the ` or X position, the manual
settings take precedence over the daytime run-
ning lamps.
Canada only: The daytime running lamps
improve the visibility of your vehicle during the
day. The daytime running lamps function is
required by law in Canada. It cannot therefore
be deactivated.124
Exterior lighting
Lights and windshield wipers

When the engine is running and the vehicle is
stationary: if you move the selector lever from a
driving position to P , the daytime running lamps
and low-beam headlamps go out after three
minutes.
When the engine is running, the vehicle is sta-
tionary and in bright ambient light: if you turn the
light switch to the ` position, the daytime
running lamps and parking lamps switch on.
If the engine is running and you turn the light
switch to the X position, the manual settings
take precedence over the daytime running
lamps.
Low-beam headlamps
G WARNING
When the light switch is set to X , the low-
beam headlamps may not be switched on
automatically if there is fog, snow or other
causes of poor visibility due to the weather
conditions such as spray. There is a risk of an
accident.
In such situations, turn the light switch to
X .
Even if the light sensor does not detect that it is
dark, the parking lamps and low-beam head-
lamps switch on when the ignition is switched on
and the light switch is set to the X position.
This is a particularly useful function in the event
of rain and fog. X
To switch on the low-beam headlamps:
turn the SmartKey in the ignition lock to posi-
tion 2 or start the engine.X
Turn the light switch to the X position.
The green X indicator lamp in the instru-
ment cluster lights up.
Parking lamps
! If the battery charge is very low, the parking
lamps or standing lamps are automatically
switched off to enable the next engine start.
Always park your vehicle safely and in a well lit
area, in accordance with the relevant legal
stipulations. Avoid using the ` parking
lamps over a period of several hours. If pos-
sible, switch on the right-hand d or left-
hand c standing lamps. X
To switch on the parking lamps: turn the
light switch to the ` position.
The green ` indicator lamp on the instru-
ment cluster lights up.
Standing lamps Switching on the standing lamps ensures the
corresponding side of the vehicle is illuminated. X
To switch on the standing lamps: turn the
SmartKey to position 0 in the ignition lock or
remove the SmartKey. X
Turn the light switch to the c (left-hand
side of the vehicle) or d (right-hand side of
the vehicle) position.
Combination switch
C
High-beam headlamps D
Turn signal, right

Front control panel X
Turn th e SmartKey to position 0 in th e ignition
loc k or remove it ( Y
page 145).X
To activate: press th e ! or V rocke r
switch up or down .
The indicator lamp in th e ! or V rocke r
switch lights up.
The blowe r will run at a low spee d regardless of
th e airflow setting .
If you activat e th e residual heat function at high
temperatures , only th e ventilation will be acti-
vated. The blowe r run s at medium speed.X
To deactivate: press th e ! or V
rocke r switch up or down .
The indicator lamp in th e ! or V rocke r
switch goes out .
Rear control panel X
Turn th e SmartKey to position 0 in th e ignition
loc k or remove it ( Y
page 145).
The RES T display appear s on th e rear com-
partmen t display.X
To activate: press rocke r switch t up or
down ( Y
page 133).
The indicator lamp in rocke r switch t lights
up. X
To deactivate: press rocke r switch t up or
down ( Y
page 133).
The indicator lamp in rocke r switch t goes
out . RES T goes out on th e rear compartmen t
display.
i If you do no t activat e th e residual heat func-
tion , RES T goes out automatically after fiv e
minute s on th e rear compartmen t display.
Residual heat is deactivated automatically: R
after approximately 30 minute si f the residual
heat function is activated in the front or rear
compartment R
after approximately 15 minutes if the residual
heat function is activated in the front and rear
compartments R
when the ignition is switched on R
if the battery voltage drops Perfume atomizer
Operating the perfume atomizer
G WARNING
If children open the vial, they could drink the
perfume or it could come into contact with
their eyes. There is a risk of injury. Do not
leave children unsupervised in the vehicle.
If the perfume liquid has been drunk, consult
a doctor. If perfume comes into contact with
your eyes or skin, rinse the eyes with clean
water. If you continue to experience difficul-
ties, consult a doctor.
H Environmental note
Full vials must not be dis-
posed of with household
waste. They must be collec-
ted separately and recycled
to protect the environment.
Dispose of full vials in an
environmentally responsible
manner and take them to a
harmful substance collec-
tion point.
C
Vial lid
D
Vial
The perfume atomizer helps to improve driving
comfort.
Via the multimedia system you can: R
switch the perfume atomizer on/off R
regulate the perfume intensity ( Y
page 274).Operating the climate control systems 141
Climate control Z

In addition, at least one of the following condi-
tions must be fulfilled: R
the engine is switched off R
the driver is not wearing a seat belt and the
driver's door is opened R
there is a system malfunction R
the power supply is insufficient R
the vehicle is stationary for a lengthy period
The red I (USA only) or $ (Canada only)
indicator lamp in the instrument cluster lights
up.
The electric parking brake is not automatically
engaged if the engine is switched off by the ECO
start/stop function.
Releasing automatically The electric parking brake is released automat-
ically when all of the following conditions are
fulfilled: R
the engine is running. R
the transmission is in position D or R .R
the seat belt has been fastened R
you depress the accelerator pedal
If the automatic transmission is in position R ,
the trunk lid must be closed.
If your seat belt is not fastened, the following
conditions must be fulfilled to automatically
release the electric parking brake: R
the driver's door is closed. R
you have shifted out of transmission position
P or you have previously driven faster than
2 mph (3 km/h).
Ensure that you do not depress the accelerator
pedal unintentionally. Otherwise the parking
brake will be released and the vehicle will start
to move.
Emergency braking The vehicle can also be braked during an emer-
gency by using the electric parking brake. X
While driving, push handle C of the electric
parking brake ( Y
page 163).
The vehicle is braked as long as you keep
handle C of the electric parking brake
pressed. The longer electric parking brake
handle C is depressed, the greater the brak-
ing force. During braking: R
a warning tone sounds R
the Please Release Parking Brake mes-
sage appears R
the red I (USA only) or $ (Canada
only) indicator lamp in the instrument cluster
flashes
When the vehicle has been braked to a stand-
still, the electric parking brake is engaged.
Parking the vehicle for a long period If you leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharging.
If you leave the vehicle parked for longer than six
weeks, the vehicle may suffer damage as a
result of lack of use. X
Visit a qualified specialist workshop and seek
advice.
Hybrid vehicles: observe the notes on the high-
voltage battery in the separate Operator's Man-
ual.
Driving tips
General driving tips
Important safety notes
G WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect,
for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving.
G WARNING
If you operate mobile communication equip-
ment while driving, you will be distracted from
traffic conditions. You could also lose control
of the vehicle. There is a risk of an accident.
Only operate this equipment when the vehicle
is stationary.164
Driving tips
Driving and parking

! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately. Drive
on for a short while. This allows the airflow to
cool the brakes more quickly.
Wet roads If you have driven for a long time in heavy rain
without braking, there may be a delayed reac-
tion from the brakes when braking for the first
time. This may also occur after the vehicle has
been washed or driven through deep water.
You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle in front.
After driving on a wet road or having the vehicle
washed, brake firmly while paying attention to
the traffic conditions. This will warm up the
brake discs, thereby drying them more quickly
and protecting them against corrosion.
Limited braking performance on salt-
treated roads If you drive on salted roads, a layer of salt resi-
due may form on the brake discs and brake
pads. This can result in a significantly longer
braking distance. R
In order to prevent any salt build-up, apply the
brakes occasionally while paying attention to
the traffic conditions. R
Carefully depress the brake pedal and the
beginning and end of a journey. R
Maintain a greater distance to the vehicle
ahead.
Servicing the brakes
! The brake fluid level may be too low, if: R
if the red brake warning lamp lights up in
the instrument cluster and R
you hear a warning tone while the engine is
running
Observe additional warning messages in the
multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines. Have the brake system checked immediately.
Consult a qualified specialist workshop to
arrange this.
! Vehicles with 4MATIC: function or per-
formance tests may only be carried out on a 2-
axle dynamometer. If you wish to operate the
vehicle on such a dynamometer, please con-
sult a qualified specialist workshop in
advance. You could otherwise damage the
drive train or the brake system.
! Vehicles with 4MATIC: the ESP ®
system
operates automatically. The engine and the
ignition must therefore be switched off (the
SmartKey must be in position 0 or 1 in the
ignition lock or the Start/Stop button must be
in position 0 or 1 ) if the electric parking brake
is tested on a brake dynamometer.
Braking triggered automatically by ESP ®
may
cause severe damage to the brake system.
! Vehicles without 4MATIC: the ESP ®
sys-
tem operates automatically. The engine and
the ignition must therefore be switched off
(the SmartKey must be in position 0 or 1 in the
ignition lock or the Start/Stop button must be
in position 0 or 1 ) if: R
the electric parking brake is tested using a
brake dynamometer. R
the vehicle is towed with one axle raised.
Braking triggered automatically by ESP ®
may
cause severe damage to the brake system.
All checks and maintenance work on the brake
system must be carried out at a qualified spe-
cialist workshop.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
If the brake system has only been subject to
moderate loads, you should test the functional-
ity of your brakes at regular intervals.
Information on BAS (Brake Assist) ( Y
page 66)
and BAS PLUS (Brake Assist PLUS) ( Y
page 67).
For safety reasons, Mercedes-Benz recom-
mends only installing the following brake disks
and brake pads/linings: R
brake disks that have been approved by
Mercedes-Benz R
brake pads/linings that have been approved
by Mercedes-Benz or that are of an equiva lent
standard of quality
Other brake disks or brake pads/linings can
compromise the safety of your vehicle. Driving tips 167
Driving and parking Z