2017 MERCEDES-BENZ S CLASS lock

function which has not been changed manually,
however, continues to be controlled automati-
cally. When the manually set function switches
back to automatic mode, the AUTO display
reappears in the rear-compartment display.
Adjusting the climate mode settings In automatic mode you can select the following
airflow settings for the driver's and front-
passenger areas:
FOCUS high airflow, slightly cooler setting
MEDIUM medium airflow, standard setting
DIFFUSE low airflow, slightly warmer and draft-
free settingX
To set: set the climate mode using the mul-
timedia system ( Y
page 274).
Setting the temperature
General notes
You can set the temperature separately for the
following areas on vehicles without rear-com-
partment climate control: R
front footwells, left and right R
driver and front passenger area You can set the temperature separately for the
following areas on vehicles with rear-compart-
ment climate control: R
front footwells, left and right R
driver and front passenger area R
rear compartment, left and right
Setting the temperature in the front
compartment using the front control
panel X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 145). X
To increase or reduce: press the

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

Setting the air vents
Important safety notes
G WARNING
Very hot or very cold air can flow from the air
vents. This could result in burns or frostbite in
the immediate vicinity of the air vents. There
is a risk of injury.
Make sure that all vehicle occupants always
maintain a sufficient distance to the air out-
lets. If necessary, redirect the airflow to
another area of the vehicle interior.
In order to ensure the direct flow of fresh air
through the air vents into the vehicle interior,
please observe the following notes: R
keep the air inlet between the windshield and
the hood free of blockages, such as ice, snow
or leaves. R
never cover the air vents or air intake grilles in
the vehicle interior.
Setting the air vents Air vents are located: R
on the left and right-hand side of the dash-
board R
in the middle of the dashboard R
in the glove box R
in the rear-compartment center console R
on the left and right in the rear compartment,
depending on the vehicle's equipment
Example: side air vent
C
Side window defroster vent
D
Side air vent

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

Problems with the engine Problem
Possible causes/consequences and P Solutions
The engine does not
start. The starter motor
can be heard. R
There is a malfunction in the engine electronics. R
There is a malfunction in the fuel supply.
Before attempting to start the engine again: X
Turn the SmartKey back to position Z in the ignition lock.
or X
Press the Start/Stop button repeatedly until all indicator lamps in
the instrument cluster go out. X
Try to start the engine again ( Y
page 146). Avoid excessively long
and frequent attempts to start the engine as these will drain the
battery.
If the engine does not start after several attempts: X
Consult a qualified specialist workshop.
The engine does not
start. You cannot hear
the starter motor. The on-board voltage is too low because the battery is too weak or
discharged. X
Jump-start the vehicle ( Y
page 335).
If the engine does not start despite attempts to jump-start it: X
Consult a qualified specialist workshop.
The starter motor was exposed to a thermal load that was too high. X
Try to start the engine again.
If the engine still does not start: X
Consult a qualified specialist workshop.
The engine is not running
smoothly and is misfir-
ing. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system. X
Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it. X
Have the cause rectified immediately at a qualified specialist work-
shop.
The coolant temperature
gauge shows a value
above 248 ‡ (120 †). The coolant level is too low. The coolant is too hot and the engine is no
longer being cooled sufficiently. X
Stop as soon as possible and allow the engine and the coolant to
cool down. X
Check the coolant level ( Y
page 316). Observe the warning notes
as you do so and add coolant if necessary. Driving 151
Driving and parking Z