light MERCEDES-BENZ CLS 2018 Service Manual

The blue W indicator lamp on the instru-
ment cluster lights up when the high-beam
headlamps are switched on. X
To switch off the high-beam headlamps:
move the combination switch back to its nor-
mal position.
The blue W indicator lamp on the instru-
ment cluster goes out.
Vehicles with Adaptive Highbeam Assist: if
Adaptive Highbeam Assist is activated, it auto-
matically controls activation and deactivation of
the high-beam headlamps ( Y
page 107).X
High-beam flasher: pull the combination
switch in the direction of arrow

late. In this, or in similar situations, the auto-
matic high-beam headlamps will not be deac-
tivated or will be activated regardless. There is
a risk of an accident.
Always carefully observe the traffic conditions
and switch off the high-beam headlamps in
good time.
Adaptive Highbeam Assist cannot take into
account road, weather or traffic conditions.
Adaptive Highbeam Assist is only an aid. You are
responsible for adjusting the vehicle's lighting
to the prevailing light, visibility and traffic con-
ditions.
In particular, the detection of obstacles can be
impaired if: R
there is poor visibility, e.g. due to fog, heavy
rain or snow R
there is dirt on the sensors or anything else
covering the sensors
Switching Adaptive Highbeam Assist
on/off X
To switch on: turn the light switch to the
X position.X
Press the combination switch forwards
beyond the pressure point ( Y
page 106).
The

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

Problems with the windshield wipers Problem
Possible causes/consequences and P Solutions
The windshield wipers
are jammed. Leaves or snow, for example, are obstructing windshield wiper move-
ment. The wiper motor has been deactivated. X
Switch off the engine. X
Remove the SmartKey from the ignition lock.
or, on vehicles with KEYLESS ‑ GO:X
Open the driver's door.
The vehicle electronics now have status 0 . This is the same as the
SmartKey having been removed. X
Remove the cause of the obstruction. X
Switch the windshield wipers back on.
The windshield wipers
fail completely. The windshield wiper drive is malfunctioning. X
Select another wiper speed on the combination switch. X
Have the windshield wipers checked at a qualified specialist work-
shop.
The windshield washer
fluid from the spray noz-
zles no longer hits the
center of the windshield. The spray nozzles are misaligned. X
Have the spray nozzles adjusted at a qualified specialist workshop. Windshield wipers 111
Lights and windshield wipers Z

Problems with the "Cooling with air dehumidification" function Problem
Possible causes/consequences and P Solutions
The indicator lamp in the
Z button flashes
three times or remains
off. The "Cooling with air
dehumidification" func-
tion cannot be switched
on. Cooling with air dehumidification has been deactivated due to a mal-
function. X
Visit a qualified specialist workshop.
Setting climate control to automatic
General notes In automatic mode, the set temperature is main-
tained automatically at a constant level. The
system automatically regulates the temperature
of the dispensed air, the airflow and the air dis-
tribution.
The "Cooling with air dehumidification" function
is activated automatically in automatic mode.
Automatic control X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 123).X
Set the desired temperature. X
To switch on: press the X button.
The indicator lamp in the X button lights
up. Automatic air distribution and airflow are
activated.
3-zone automatic climate control: when auto-
matic mode is activated, you can set the climate
mode ( Y
page 117).X
To switch to manual mode: press the

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

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 76).
Do not keep the KEYLESS-GO key: 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 KEYLESS-GO.
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.
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 KEYLESS-GO
C
Start/Stop button
D
Ignition lock
As soon as the ignition is switched on, all the
indicator lamps in the instrument cluster light
up. Indicator and warning lamps, see
( Y
page 226). 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.
If you press Start/Stop button C once when
in this position, the ignition is deactivated
again.
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
vehi cle. 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.124
Driving
Dr ivi ng an d parking

R
the system detects that the windshield is not
fogged up when the air-conditioning system is
switched on R
the hood is closed R
the driver's door is closed and the driver's
seat belt is fastened
i All of the vehicle's systems remain active
when the engine is stopped automatically.
i The HOLD function can also be activated if
the engine has been switched off automati-
cally. It is then not necessary to continue
applying the brakes during the automatic stop
phase. When you depress the accelerator
pedal, the engine starts automatically and the
braking effect of the HOLD function is deac-
tivated.
Automatic engine switch-off can take place a
maximum of four times in a row (initial stop, then
three subsequent stops).
Mercedes-AMG vehicles: the number of con-
secutive automatic engine switch-offs is unlimi-
ted.
All other models: automatic engine switch-off
can take place a maximum of four times in a row
(initial switch-off, then three subsequent switch-
offs).
Automatic engine start The engine starts automatically if: R
you switch off the ECO start/stop function by
pressing the ECO button R
in transmission position D or N the brake
pedal is released and the HOLD function is not
active R
you depress the accelerator pedal R
you engage reverse gear RR
you move the transmission out of position PR
you switch to drive program S , S+ or M
(Mercedes-AMG vehicles) R
you unfasten your seat belt or open the driv-
er's door R
the vehicle starts to roll R
the brake system requires this R
the temperature in the vehicle interior devi-
ates from the set range R
the system detects moisture on the wind-
shield when the air-conditioning system is
switched on R
the battery's condition of charge is too low i Shifting the transmission to position P does
not start the engine.
Deactivating or activating the ECO
start/stop function Mercedes-AMG vehicles X
To deactivate: in drive program C , press ECO
button C .
or X
Switch to drive program S , S+ or M
( Y
page 134).
Indicator lamp D goes out.X
To activate: press ECO button C .
Indicator lamp D lights up.
If drive program S , S+ or M is active, the auto-
matic transmission switches to drive program
C .
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.
All other models Driving 127
Dr ivi ng an d parking Z

X
To deactivate: press ECO button C .
Indicator lamp D goes out.X
To activate: press ECO button C .
Indicator lamp D lights up.
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 an d parking