engine MERCEDES-BENZ S CLASS 2017 Service Manual

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

Overview of climate control systems
General notes Observe the settings recommended on the fol-
lowing pages. The windows could otherwise fog
up.
To prevent the windows from fogging up: R
switch off climate control only briefly R
switch on air-recirculation mode only briefly R
switch on the cooling with air dehumidifica-
tion function R
switch on the defrost windshield function
briefly, if required
Climate control regulates the temperature and
air humidity in the vehicle interior. The air filter
cleans the air, thus improving the interior cli-
mate.
The "Cooling with air dehumidification" function
is available only when the engine is running.
Optimum climate control is only achieved with
the side windows and roof closed.
If you start the engine using your smartphone,
the last selected climate control setting is reac-
tivated ( Y
page 147).
The residual heat function can only be activated
or deactivated with the ignition switched off
( Y
page 140).
To enable the air conditioning, pollutant moni-
toring and air filtering systems to function cor-
rectly, an interior filter must be used at all times.
Ensure that the filter is properly installed and
that the filter housing in the engine compart-
ment is correctly and tightly sealed by the cover at all times during operation. Use filters that
have been recommended and approved by
Mercedes-Benz. Always have service work car-
ried out at a qualified specialist workshop.
The integrated filter filters out most particles of
dust and soot and completely filters out pollen.
It also reduces gaseous pollutants and odors. A
clogged filter reduces the amount of air supplied
to the vehicle interior. For this reason, you
should always observe the interval for replacing
the filter, which is specified in the Maintenance
Booklet. As it depends on environmental condi-
tions, e.g. heavy air pollution, the interval may
be shorter than stated in the Maintenance Book-
let.
i Ventilate the vehicle for a brief period during
warm weather, e.g. using the convenience
opening feature ( Y
page 92). This will speed
up the cooling process and the desired inte-
rior t emper ature will be reached more
quickly.
i It is possible that the blower may be activa-
ted automatically 60 minutes after the Smart-
Key has been removed depending on various
factors, e.g. the outside temperature. In vehi-
cles with the KEYLESS-GO or KEYLESS-GO
start function, the blower can switch on auto-
matically after the engine has been switched
off and the door opened. The vehicle is then
ventilated for 30 minutes to dry the automatic
climate control.
i Hybrid vehicles: observe the notes on cli-
mate control in the separate Operator's Man-
ual.132
Overview of climate control systems
Climate control

Problems with the rear window defroster Problem
Possible causes/consequences and P Solutions
The rear window
defroster has deactiva-
ted prematurely or can-
not be activated. The battery has not been sufficiently charged. X
Switch off any consumers that are not required, e.g. reading lamps,
interior lighting or the seat heating.
When the battery is sufficiently charged, the rear window defroster
can be activated again.
Switching air-recirculation mode
on/off
General notes You can also temporarily deactivate the flow of
fresh air manually if unpleasant odors are enter-
ing the vehicle from outside. The air already
inside the vehicle will then be recirculated.
If you switch on air-recirculation mode, the win-
dows can fog up more quickly, in particular at
low temperatures. Only use air-recirculation
mode briefly to prevent the windows from fog-
ging up.
Activating/deactivating X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 145).X
To activate: press the r rocker switch up
or down.
The indicator lamp in the r rocker switch
lights up.
Air-recirculation mode switches on automati-
cally: R
at high outside temperatures R
at high levels of pollution R
in a tunnel
The indicator lamp in the r rocker switch is
not lit when automatic air-recirculation mode is
activated. Outside air is added after about
30 minutes. X
To deactivate: press the r rocker switch
up or down.
The indicator lamp in the r rocker switch
goes out. Air-recirculation mode deactivates automati-
cally: R
after approximately five minutes at outside
temperatures below approximately 41 ‡
(5 †) R
after approximately five minutes if cooling
with air dehumidification is deactivated R
after approximately 30 minutes at outside
temperatures above approximately 41 ‡
(5 †) if the "Cooling with air dehumidifica-
tion" function is activated
Switching the residual heat on or off
General notes Vehicles with rear-compartment climate
control: once the engine is switched off, it is
possible to make use of the residual heat of the
engine to continue heating or ventilating the
rear and front compartment of the vehicle for
approximately 15 minutes. If the "Residual heat"
function is set for only the front or only the rear
compartment, it is possible to continue heating
or ventilating for approximately 30 minutes.
Vehicles without rear-compartment climate
control: once the engine is switched off, it is
possible to make use of the residual heat of the
engine to continue heating or ventilating the
front compartment of the vehicle for approx-
imately 30 minutes.
The heating or ventilation time depends on the
temperature that has been set.140
Operating the climate control systems
Climate control

Notes on breaking-in a new vehicle
Important safety notes The sensor system of some driving and driving
safety systems adjusts automatically while a
certain distance is being driven after the vehicle
has been delivered or after repairs. Full system
effectiveness is not reached until the end of this
teach-in procedure.
New and replaced brake pads and discs only
reach their optimum braking effect after several
hundred kilometers of driving. Compensate for
this by applying greater force to the brake pedal.
The first 1000 miles (1500 km) The more you look after the engine when it is
new, the more satisfied you will be with its per-
formance in the future. R
You should therefore drive at varying vehicle
and engine speeds for the first 1000 miles
(1500 km). R
Avoid heavy loads, e.g. driving at full throttle,
during this period. R
When shifting gears manually, upshift in good
time, before the tachometer needle reaches

There is a risk of fire and an accident. Release
the parking brake fully before driving off.
! Do not warm up the engine with the vehicle
stationary. Drive off immediately. Avoid high
engine speeds and driving at full throttle until
the engine has reached its operating temper-
ature.
Only shift the automatic transmission to the
desired drive position when the vehicle is sta-
tionary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery roads.
You could otherwise damage the drive train.
! At low engine oil temperatures under 68 ‡
(+20 †), the maximum engine speed is limi-
ted in order to protect the engine. To protect
the engine and maintain smooth engine oper-
ation, avoid driving at full throttle when the
engine is cold.
Hybrid vehicles: make sure that you read the
separate operating instructions. Otherwise, you
may not recognize dangers.
SmartKey positions
SmartKey
Z
To remove the SmartKey
G
Power supply for some consumers, such as
the windshield wipers
H
Ignition (power supply for all consumers)
and drive position
I
To start the engine
The SmartKey can be turned in the ignition lock
even if it is not the correct SmartKey for the
vehicle. The ignition is not switched on. The
engine cannot be started. Start/Stop button General notes All vehicles are equipped with a removable
Start/Stop button.
The Start/Stop button must be inserted in the
ignition lock and the SmartKey must be in the
vehicle.
When you insert the Start/Stop button into the
ignition lock, the system needs approximately
two seconds recognition time. You can then use
the Start/Stop button.
Pressing the Start/Stop button several times in
succession corresponds to the different Smart-
Key positions in the ignition lock. This is only the
case if you are not depressing the brake pedal.
If you depress the brake pedal and press the
Start/Stop button, the engine starts immedi-
ately.
A check which periodically establishes a radio
connection between the vehicle and the Smart-
Key determines whether a valid SmartKey is in
the vehicle. This occurs, for example, when
starting the engine.
To start the vehicle without actively using the
SmartKey: R
the Start/Stop button must be inserted in the
ignition lock. R
the SmartKey must be in the vehicle. R
the vehicle must not be locked with the
SmartKey or KEYLESS-GO ( Y
page 78).
Do not keep the SmartKey: R
with electronic devices, e.g. a mobile phone
or another SmartKey. R
with metallic objects, e.g. coins or metal foil. R
inside metallic objects, e.g. a metal case.
This can affect the functionality of the Smart-
Key.
Do not keep the SmartKey in the temperature-
controlled cup holder ( Y
page 292). Otherwise,
the SmartKey will not be detected, e.g. when
starting the engine with the Start/Stop button.
If you lock the vehicle with the SmartKey's
remote control or with KEYLESS-GO, after a
short time: R
you will not be able to switch on the ignition
with the Start/Stop button. R
you will not be able to start the engine with the
Start/Stop button until the vehicle is
unlocked again. Driving 145
Driving and parking Z

If you lock the vehicle centrally using the button
on the front door ( Y
page 83), you can continue
to start the engine with the Start/Stop button.
The engine can be switched off while the vehicle
is in motion by pressing and holding the Start/
Stop button for three seconds. This function
operates independently of the ECO start/stop
automatic engine switch-off function.
Key positions with the Start/Stop button
C
Start/Stop buttonD
Ignition lock
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. Warning and indicator lamps: see
( Y
page 258).
If Start/Stop button C has not yet been
pressed, this corresponds to the SmartKey
being removed from the ignition. X
To switch on the power supply: press
Start/Stop button C once.
The power supply is switched on. You can now
activate the windshield wipers, for example.
The power supply is switched off again if: R
the driver's door is opened and R
you press Start/Stop button C twice when in
this position X
To switch on the ignition: press Start/Stop
button C twice.
The ignition is switched on.
The ignition is switched off again if: R
you do not start the engine within 15 minutes
when in this position R
you press Start/Stop button C twice when in
this position. The power supply is switched off again if: R
the driver's door is opened and R
you press Start/Stop button C twice when in
this position
Removing the Start/Stop button You can remove the Start/Stop button from the
ignition lock and start the vehicle as normal
using the SmartKey.
It is only possible to switch between Start/Stop
button mode and SmartKey operation when the
transmission is in position P .X
Remove Start/Stop button C from ignition
lock D .
You do not have to remove the Start/Stop but-
ton from the ignition lock when you leave the
vehicle. You should, however, always take the
SmartKey with you when leaving the vehicle. As
long as the SmartKey is in the vehicle: R
the vehicle can be started using the Start/
Stop button R
the electrically powered equipment can be
operated
Starting the engine
Important safety notes
G WARNING
If children are left unsupervised in the vehicle,
they could: R
open the doors, thus endangering other
people or road users. R
get out and disrupt traffic. R
operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake. R
shifting the automatic transmission out of
park position P R
Start 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 the146
Driving
Driving and parking

vehicle. Always keep the SmartKey out of
reach of children.
G WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There
is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation.
G WARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or
parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
General notes During a cold start, the engine runs at higher
speeds to enable the catalytic converter to
reach its operating temperature. The sound of
the engine may change during this time.
Automatic transmission X
Shift the transmission to position P
( Y
page 152).
The transmission position display in the mul-
tifunction display shows P ( Y
page 154).
You can start the engine in transmission posi-
tion P and N .
Starting procedure with the SmartKey To start the engine using the SmartKey instead
of the Start/Stop button, pull the Start/Stop
button out of the ignition lock. X
Turn the SmartKey to position 3 in the ignition
lock and release it as soon as the engine is
running ( Y
page 145). Starting procedure with the Start/Stop
button The Start/Stop button can be used to start the
vehicle manually without inserting the SmartKey
into the ignition lock. The Start/Stop button
must be inserted in the ignition lock and the
SmartKey must be in the vehicle. This mode for
starting the engine operates independently of
the ECO start/stop automatic engine start func-
tion.
You can start the engine if a valid SmartKey is in
the vehicle. Always take the SmartKey with you
when leaving the vehicle, even if you only leave
it for a short time. Pay attention to the important
safety notes. X
Depress the brake pedal and keep it
depressed. X
Press the Start/Stop button once
( Y
page 145).
The engine starts.
Starting procedure via smartphone Observe the important safety notes on starting
the engine ( Y
page 146).
You can also start your engine via your smart-
phone from outside the vehicle. In this case, the
previously selected climate control setting is
activated. In this way you can cool or heat the
interior of the vehicle before starting the jour-
ney.
Only start the engine via your smartphone if it is
safe to start and run the engine where your vehi-
cle is parked.
Observe the legal stipulations in the area where
your vehicle is parked. Engine start via smart-
phone may be limited to certain countries or
regions.
You can execute a maximum of two consecutive
starting attempts via your smartphone. If you
insert the SmartKey into the ignition lock, you
can carry out two more starting attempts.
Once you have started the engine, you can
switch the engine off via your smartphone at any
time.
You can only start the engine via your smart-
phone if: R
the SmartKey is in the ignition lock R
park position P is selected R
the accelerator pedal is not depressed R
the anti-theft alarm system is not activated Driving 147
Driving and parking Z

R
the panic alarm is not activated R
the hazard warning lamps are switched off R
the hood is closed. R
the doors are closed and locked R
the windows and sliding sunroof are closed
Also make sure that: R
the fuel tank is sufficiently filled R
the starter battery is sufficiently charged
G WARNING
Limbs could be crushed or trapped if the
engine is started unintentionally during ser-
vice or maintenance work. There is a risk of
injury.
Always secure the engine against uninten-
tional starting before carrying out mainte-
nance or repair work.
Make sure that the engine cannot be started via
your smartphone before carrying out mainte-
nance or repairs. You can prevent an engine
start via your smartphone, for example, if you: R
switch on the hazard warning lamps R
do not lock the doors R
open the hood
Pulling away
General notes
G WARNING
If the engine speed is above the idling speed
and you engage transmission position D or R ,
the vehicle could pull away suddenly. There is
a risk of an accident.
When engaging transmission position D or R ,
always firmly depress the brake pedal and do
not simultaneously accelerate.
Depress the accelerator carefully when pulling
away.
The vehicle locks centrally once you have pulled
away. The locking knobs in the doors drop down.
You can open the doors from the inside at any
time.
You can also deactivate the automatic locking
feature ( Y
page 84). It is only possible to shift the transmission from
position P to the desired position if you depress
the brake pedal. Only then is the parking lock
released.
If you do not depress the brake pedal, the
DIRECT SELECT lever can still be moved but the
parking lock remains engaged.
i Upshifts take place at higher engine speeds
after a cold start. This helps the catalytic con-
verter to reach its operating temperature
more quickly.
Information on the automatic release of the
electric parking brake ( Y
page 164).
Hill start assist Hill start assist helps you when pulling away for-
wards or in reverse on an uphill gradient. It holds
the vehicle for a short time after you have
removed your foot from the brake pedal. This
gives you enough time to move your foot from
the brake pedal to the accelerator pedal and to
depress it before the vehicle begins to roll.
G WARNING
After a short time, hill start assist will no lon-
ger brake your vehicle and it could roll away.
There is a risk of an accident and injury.
Therefore, quickly move your foot from the
brake pedal to the accelerator pedal. Never
leave the vehicle when it is held by hill start
assist.
Hill start assist is not active if: R
you are pulling away on a level road or on a
downhill gradient. R
the transmission is in position \\ .R
the electric parking brake is applied. R
ESP ®
is malfunctioning.
ECO start/stop function
Introduction
Hybrid vehicles: observe the notes on the ECO
start/stop function in the separate operating
instructions.
The ECO start/stop function switches the
engine off automatically if the vehicle is stopped
under certain conditions.148
Driving
Dr ivi ng an d parking

The engine starts automatically when the driver
wants to pull away again. The ECO start/stop
function thereby helps you to reduce the fuel
consumption and emissions of your vehicle.
Important safety notes
G WARNING
If the engine is switched off automatically and
you exit the vehicle, the engine is restarted
automatically. The vehicle may begin moving.
There is a risk of accident and injury.
If you wish to exit the vehicle, always turn off
the ignition and secure the vehicle against
rolling away.
General notes
C
ECO start/stop display
The ECO start/stop function is activated when-
ever you switch on the engine using the Smart-
Key or the Start/Stop button.
If the engine has been switched off automati-
cally by the ECO start/stop function, the