key battery MERCEDES-BENZ CLS 2017 User Guide

USA only: the daytime running lamps improve
the visibility of your vehicle during the day. To do
this, the Daytime running lamps
function
must be switched on using the on-board com-
puter ( Y
page 198).
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.
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

Rear-compartment overhead control
panel
C
= Switches the right-hand reading lamp
on/offD
= Switches the left-hand reading lamp
on/off
Interior lighting control
General notes In order to prevent the vehicle's battery from
discharging, the interior lighting functions are
automatically deactivated after some time
except for when the SmartKey is in position 2 in
the ignition lock.
The color and brightness of the ambient lighting
may be set using the on-board computer
( Y
page 198).
Automatic interior lighting control X
To switch on or off: press the 3 button.
When the automatic interior lighting control is
activated, the button is flush with the over-
head control panel.
The interior lighting automatically switches on if
you: R
unlock the vehicle R
open a door. R
remove the SmartKey from the ignition lock
The interior light is activated for a short while
when the SmartKey is removed from the ignition
lock. You can activate this delayed switch-off
using the on-board computer ( Y
page 199). Replacing bulbs The front and rear light clusters of your vehicle
are equipped with LED light bulbs. Do not
replace the LED light sources of your vehicle
yourself. Contact a qualified specialist work-
shop which has the necessary specialist knowl-
edge and tools to carry out the work required.
Lamps are an important aspect of vehicle safety.
You must therefore make sure that these func-
tion correctly at all times. Have the headlamp
setting checked regularly.
Windshield wipers
Switching the windshield wipers
on/off
! Do not operate the windshield wipers when
the windshield is dry, as this could damage
the wiper blades. Moreover, dust that has col-
lected on the windshield can scratch the glass
if wiping takes place when the windshield is
dry.
If it is necessary to switch on the windshield
wipers in dry weather conditions, always use
washer fluid when operating the windshield
wipers.
! If the windshield wipers leave smears on the
windshield after the vehicle has been washed
in an automatic car wash, wax or other resi-
dues may be the reason for this. Clean the
windshield using washer fluid after washing
the vehicle in an automatic car wash.
! Intermittent wiping with rain sensor: due to
optical influences and the windshield becom-
ing dirty in dry weather conditions, the wind-
shield wipers may be activated inadvertently.
This could then damage the windshield wiper
blades or scratch the windshield.
For this reason, you should always switch off
the windshield wipers in dry weather.Windshield wipers 109
Lights and windshield wipers Z

Switch off the "Windshield defrosting" function
as soon as the windshield is clear again. X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 123).X
To activate: press the d button.
The indicator lamp in the d button lights
up.
The climate control system switches to the
following functions: R
high airflow R
high temperature R
air distribution to the windshield and front
side windows R
air-recirculation mode off
If the battery is not sufficiently charged, blower
output may be reduced. Once the battery is suf-
ficiently charged again, full blower output will be
available again. X
To deactivate: press the d button.
The indicator lamp in the d button goes
out. The previously selected settings are
restored. Air-recirculation mode remains
deactivated.
MAX COOL maximum cooling The MAX COOL function is only available in vehi-
cles for the USA.
MAX COOL is only operational when the engine
is running. X
To activate: 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 deactivate the flow of fresh air if
unpleasant odors are entering 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 123).X
To activate: press the r button.
The indicator lamp in the r button lights
up.
Dual-zone automatic climate control: air-recir-
culation mode is automatically activated at high
outside temperatures.
3-zone automatic climate control: air-recircula-
tion mode is automatically activated at high lev-
els of pollution or at high outside temperatures.
When air-recirculation mode is activated auto-
matically, the indicator lamp above the r
button does not light up. Outside air is added
after approximately 30 minutes. X
To deactivate: press the r button.
The indicator lamp in the r button 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 The residual heat function is only available with
3-zone automatic climate control.
It is possible to make use of the residual heat of
the engine to continue heating the vehicle for
approximately 30 minutes after the engine has
been switched off. The heating time depends on
the set interior temperature.
Activating/deactivating X
Turn the SmartKey to position 0 in the ignition
lock or remove it ( Y
page 123).X
To switch on: press the K button.
The indicator lamp in the K button lights
up.
If the residual heat function is activated, the
windows may fog up on the inside.
The blower will run at a low speed regardless of
the airflow setting.
If you activate the residual heat function at high
temperatures, only the ventilation will be acti-
vated. The blower runs at medium speed.120
Operating the climate control systems
Climate control

If indicator lamp D is off, the ECO start/stop
function has been deactivated manually or as
the result of a malfunction. The engine will then not be switched off automatically when the vehi-
cle stops.
Problems with the engine Problem
Possible causes/consequences and P Solutions
The engine does not
start. The HOLD function or DISTRONIC PLUS is activated. X
Deactivate the HOLD function ( Y
page 157) or DISTRONIC PLUS
( Y
page 155). X
Try to start the engine again.
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 0 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 124). 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 285).
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
Allow the starter motor to cool down for approximately two minutes. X
Try to start the engine again.
If the engine still does not start: X
Consult a qualified specialist workshop.128
Driving
Driving and parking

Problem
Possible causes/consequences and P Solutions
The SmartKey battery is discharged or nearly discharged. X
Unlock the vehicle using the mechanical key ( Y
page 78).X
Open the trunk lid. X
Manually unlock the fuel filler flap using the emergency release
( Y
page 140).
The fuel filler flap is unlocked, but the opening mechanism is jammed. X
Consult a qualified specialist workshop.
Parking
Important safety notes
G WARNING
Flammable material such as leaves, grass or
twigs may ignite if they come into contact with
hot parts of the exhaust system or exhaust
gas flow. There is a risk of fire.
Park the vehicle so that no flammable mate-
rials come into contact with parts of the vehi-
cle which are hot. Take particular care not to
park on dry grassland or harvested grain
fields.
G WARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example: R
release the parking brake. R
shift the automatic transmission out of the
parking position P .R
start the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
! Always secure the vehicle correctly against
rolling away. Otherwise, the vehicle or its driv-
etrain could be damaged. To ensure that the vehicle is secured against
rolling away unintentionally: R
the parking brake must be applied. R
the transmission must be in position P and the
Smartkey must be removed from the ignition
lock. R
the front wheels must be turned towards the
curb on steep uphill or downhill gradients.
Switching off the engine
Important safety notes
G WARNING
The automatic transmission switches to neu-
tral position N when you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P . Prevent the parked vehi-
cle from rolling away by applying the parking
brake.
Vehicles with automatic transmission X
Apply the parking brake firmly. X
All vehicles (except Mercedes-AMG vehi-
cles): shift the transmission to position P .Parking 141
Driving and parking Z

Your attention must always be focused on the
traffic conditions. Only use the cigarette lighter
when road and traffic conditions permit.
Cigarette lighter in the front compart-
ment
Mercedes-AMG vehicles X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 123).X
To open: briefly press the trim on cover C .
The stowage compartment opens. X
Press in cigarette lighter D .
Cigarette lighter D will pop out automatically
when the heating element is red-hot.
All other models X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 123).X
To open: slide cover C forwards until it
engages. X
Press in cigarette lighter D .
Cigarette lighter D will pop out automatically
when the heating element is red-hot. X
To close: briefly press cover C at the front.
The cover moves back. 12 V sockets
General notes X
Turn the SmartKey to position 1 in the ignition
lock ( Y
page 123).
The sockets can be used for accessories with a
maximum draw of 180 W (15 A). Accessories
include such items as chargers for mobile
phones.
If you use the sockets for long periods when the
engine is switched off, the battery may dis-
charge.
An emergency cut-out ensures that the on-
board voltage does not drop too low. If the on-
board voltage is too low, the power to the sock-
ets is automatically cut. This ensures that there
is sufficient power to start the engine.
Socket in the front center console
Mercedes-AMG vehicles X
To open: briefly press the trim on cover C .
The stowage compartment opens. X
Lift up the cover of socket D .X
To close: fold down cover C .
All other models Features 253
Stowage and features Z

Mercedes-Benz. These batteries provide
increased impact protection to prevent vehicle
occupants from suffering acid burns should the
battery be damaged in the event of an accident.
In order for the battery to achieve the maximum
possible service life, it must always be suffi-
ciently charged.
Like other batteries, the vehicle battery may
discharge over time if you do not use the vehicle.
In this case, have the battery disconnected at a
qualified specialist workshop. You can also
charge the battery with a charger recommended
by Mercedes-Benz. Contact a qualified special-
ist workshop for further information.
Have the battery condition of charge checked
more frequently if you use the vehicle mainly for
short trips or if you leave it standing idle for a
lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked for a long period of time.
Remove the SmartKey if you park the vehicle
and do not require any electrical consumers.
The vehicle will then use very little energy, thus
conserving battery power.
If the power supply has been interrupted, e.g. if
you reconnect the battery, you will have to: R
set the clock; see the Digital Operator's Man-
ual
On vehicles with a multimedia system, the
time is set automatically. R
reset the function for folding the exterior mir-
rors in/out automatically, by folding the mir-
rors out once ( Y
page 101).
Charging the battery
! Only use battery chargers with a maximum
charging voltage of 14.8 V.
G WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a
risk of an explosion.
Particularly avoid fire, open flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery.
G WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with skin, eyes or clothing. Do
not inhale any battery gases. Do not lean over
the battery. Keep children away from batter-
ies. Wash away battery acid immediately with
plenty of clean water and seek medical atten-
tion.
G WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery, gases
can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
! Only charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment ( Y
page 285).X
Open the hood. X
Connect the battery charger to the positive
terminal and ground point in the same order
as when connecting the donor battery in the
jump-starting procedure ( Y
page 285).
Keep away from fire and open flames. Do not
lean over a battery. Never charge the battery if it
is still installed in the vehicle, unless you use a
battery charger which has been tested and
approved by Mercedes-Benz. A battery charger
unit specially adapted for Mercedes-Benz vehi-
cles and tested and approved by Mercedes-
Benz is available as an accessory. It permits the
charging of the battery in its installed position.
Contact an authorized Mercedes-Benz Center
for further information and availability. Read the
battery charger's operating instructions before
charging the battery.
If the warning and indicator lamps do not light up
on the instrument cluster when temperatures
are low, it is probably because the discharged
battery has frozen. In this case, you may neither
charge the battery nor jump-start the vehicle.
The service life of a thawed-out battery may be
shorter. The starting characteristics can be
impaired, particularly at low temperatures. Have
the thawed-out battery checked at a qualified
specialist workshop.284
Battery (vehicle)
Breakdown assistance

Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged, the
engine can be jump-started from another vehicle or from a second battery using jumper cables.
Observe the following points: R
The battery is not accessible in all vehicles. If the other vehicle's battery is not accessible, jump-
start the vehicle using a second battery or a jump-starting device. R
You may only jump-start the vehicle when the engine and exhaust system are cold. R
Only jump-start from batteries with a 12 V voltage rating. R
Only use jumper cables which have a sufficient cross-section and insulated terminal clamps. R
If the battery is fully discharged, leave the battery that is being used to jump-start connected for
a few minutes before attempting to start. This charges the battery slightly. R
Make sure that the two vehicles do not touch.
Make sure that: R
the jumper cables are not damaged. R
when the jumper cables are connected to the battery, uninsulated sections of the terminal clamp
do not come into contact with other metal sections. R
the jumper cables cannot come into contact with parts which can move when the engine is
running, such a s the V-belt pulley or the fan.X
Apply the parking brake firmly. X
Shift the transmission to position P .X
Make sure that the ignition is switched off. All indicator lamps in the instrument cluster must be
off. When using the SmartKey, turn the SmartKey to position 0 in the ignition lock and remove it
( Y
page 123).X
Switch off all electrical consumers, e.g. rear window defroster, lighting, etc. X
Open the hood.
Position number

! If you tow or tow-start another vehicle, its
weight must not exceed the maximum per-
missible gross vehicle weight of your vehicle.
It is better to have the vehicle transported than
to have it towed away.
If the vehicle has suffered transmission damage,
have it transported on a transporter or trailer.
The automatic transmission must be in position
N when the vehicle is being towed.
The battery must be connected and charged.
Otherwise, you: R
cannot turn the SmartKey to position 2 in the
ignition lock. R
cannot shift the automatic transmission to
position N .
In the event of damage to the electrical sys-
tem
If the battery is defective, the automatic trans-
mission will be locked in position P . To shift the
automatic transmission to position N , you must
provide power to the vehicle's electrical system
in the same way as when jump-starting
( Y
page 285).
Have the vehicle transported on a transporter or
trailer.
Disarm the automatic locking feature before the
vehicle is towed ( Y
page 82). You could other-
wise be locked out when pushing or towing the
vehicle.
Installing/removing the towing eye
Installing the towing eye
G WARNING
The exhaust tail pipe may be very hot. There is
a risk of burns when removing the rear cover.
Do not touch the exhaust pipe. Take particular
care when removing the rear cover. All vehicles except Mercedes-AMG vehicles
Mercedes-AMG vehicles
The brackets for the screw-in towing eye are
located in the bumpers. They are at the front and
at the rear, behind the covers. X
Remove the towing eye from the vehicle tool
kit ( Y
page 277). X
Pull cover C out of the bumper in the direc-
tion of the arrow by inserting your fingers into
the recess. X
Press the mark on cover D inwards in the
direction of the arrow. X
Remove cover D from the opening.X
Screw in the towing eye clockwise as far as it
will go and tighten it.288
Towing and tow-starting
Breakdown assistance