light MERCEDES-BENZ SLC 2017 Service Manual

Vehicles with LE Dh eadlampsThe front and rea rl ig ht cluster sofy ou rv ehicle
are equipped with LED light bulbs. Do not
replace the bulb sy ours elf. Contact aq uali fied
specialist workshop which ha st he necessary
specialist knowledge and tool stoc arry ou tt he
work required.
Overview: changin gb ulbs/bulb types
Haloge nh eadlamps
C
Low-beam headlamp :H755WD
High-beam headlamp :H755W
Changin gt he fron tb ulbs
Removing/mounting the cove ri nt he
fron tw heel housing
X
To remove: switch off the lights.X
Turn the front wheels inwards. X
Slide cover C up and remove it.X
To install: reinser tc over C and slid eitd ow n
unti lite ngages. Low-beam headlamps (haloge nh ead-
lamps) X
Remove the cove rint he front whee lh ousing
( Y
page 98). X
Turn housing cover C counter-clockwis ea nd
pull it out. X
Push bar D upwards. X
Remove connector

Problems with the windshield wipers Problem
Possible causes/consequences and P Solutions
The windshield wipers
are jammed. Leaves or snow, for example, may be obstructing the windshield wiper
movement .T he wiper motor has been deactivated. X
For safety reasons, you should remove the SmartKey from the igni-
tion lock.
or X
Switch off the engine using the Start/Stop button and open the
driver's door. 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 aq ualified 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 aq ualified specialist workshop.Windshield wipers 101
Lights and windshiel dw ipers Z

ECO start/stop function During automatic engine switch-off ,t he climate
control system only operate satar educed capa-
city. If you require full climate control capacity,
th eE CO start/sto pf unction can be deactivated
by pressin gt he ECO button ( Y
page 119).
Operating th ec limat ec ontrol sys-
tems
Activating/deactivatin gc limat ec on-
trol
General notes When th ec limate control is switched off ,t he air
supply and air circulation are also switched off.
The windows coul df og up. Therefore, switch off
climate control only briefly
i Activate climate control primarily usin gt he
X butto n( Y
page 108).
Air-conditioning system X
Turn th eS ma rtKey to position 2 in th ei gnition
loc k( Y
page 115).X
To switch on: tur na irflow control k clock-
wise to th ed esired position (excep tp osition
0 )( Y
page 103).X
To switch off: tur na irflow control k coun-
ter-clockwise to position 0 ( Y
page 103).
3-zone automatic climat ec ontrolX
Turn th eS ma rtKey to position 2 in th ei gnition
loc k( Y
page 115).X
To switch on: pres st he X button.
The indicator lamp in the X button lights
up. Airflow and air distribution are set to auto-
matic mode.
or X
Press the x button.
The indicator lamp in the x button goes
out .T he previously selecte ds ettings are
restored. X
To switch off: pres st he x button.
The indicator lamp in the x button lights
up. Switching cooling with air dehumidi-
fication on/off
General notes If you deactivate th e" Coolin gw ith air-dehumid-
ification" function ,t he air inside th ev ehicle will
no tbec ooled. The air inside th ev ehicle will also
no tbed ehumidified. The windows can fog up
mor eq uickly. Therefore, deactivate th ec ooling
with air-dehumidification function only briefly.
The "Coolin gw ith air dehumidification "f unction
is only availabl ew hen th ee ngine is running. The
air inside th ev ehicle is cooled and dehumidified
according to th et em peratur es elected.
Condensation may drip from th eu ndersid eo f
th ev ehicle when it is in cooling mode. This is
normal and no tas ign that there is am alfunc-
tion.
Activating/deactivating X
To activate: pres st he Z or V button.
The indicator lamp in the Z or V button
light su p. X
To deactivate: pres st he Z or V but-
ton.
The indicator lamp in the Z or V button
goes out .T he "Coolin gw ith air dehumidifica-
tion" function has ad elayed switch-off fea-
ture.Operating th ec limate control systems 107
Climate control

Problems with the "Cooling with air dehumidification" function Problem
Possible causes/consequences and P Solutions
The indicator lamp in the
Z or V button
flashes three times or
remains off. The "Cool-
ing with air dehumidifi-
cation" function cannot
be switched on. Cooling with air dehumidification has been deactivated due to am al-
function. X
Visit aq ualified specialist workshop.
Setting climate control to automatic
General notes Automatic mode is only available with dual-zone
automatic air conditioning.
In automatic mode, the set temperature is main-
tained automatically at ac onstant level. The
system automatically regulates the temperature
of the dispensed air, the airflow and the air dis-
tribution.
The automatic mode functions optimally when
the "Cooling with air dehumidification" function
is activated. If necessary, cooling with air dehu-
midification can be deactivated.
If you deactivate the "Cooling with air-dehumid-
ification" function, the air inside the vehicle will
not be cooled. The air inside the vehicle will also
not be dehumidified .T he windows can fog up
more quickly. Therefore, deactivate the cooling
with air-dehumidification function only briefly.
Automatic control X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 115).X
Set the desired temperature. X
To activate: press the X button.
The indicator lamp in the X button lights
up. Automatic air distribution and airflow are
activated. X
To switch to manua lm ode: press the

Problems with the rear window defroster Problem
Possible causes/consequences and P Solutions
The indicator lamp on
the l button flashes.
The rear window
defroster has deactiva-
ted prematurely or can-
not be activated. The on-board voltage is too low because too many electrical consum-
ers are switched on. 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.
The roof is open. X
Close the roof.
When the roof is closed, the rear window defroster can be activated
again.
Switching air-recirculation mode
on/off
General notes 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.
Switching on/off X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 115).X
To switch on: press the r button.
The indicator lamp in the r button lights
up.
i Air-recirculation mode is automatically acti-
vated at high levels of pollution (dual-zone
automatic climate control only) or at high out-
side temperatures. When air-recirculation
mode is activated automatically, the indicator
lamp in the r button is not lit. Outside air
is added after about 30 minutes. X
To switch off: press the r button.
The indicator lamp in the r button goes
out. i Air-recirculation mode deactivates auto-
matically: 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 on
vehicles for Canada.
It is possible to make use of the residual heat of
the engine to continue heating the stationary
vehicle for up to 30 minutesafter 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 115).X
To activate: press the K or V button.
The indicator lamp in the K or V button
lights up.
i The blower will run at al ow speed regardless
of the airflow setting.Operating the climate control systems 111
Climat ec ontrol

As soo na st he ignition is switched on, al lt he
indicator lamps in the instrument cluster light
up .F urther informatio nons it uations where an
indicator lamp either fails to go ou ta fte rs tarting
the engine or lights up whil ed riving
( Y
page 204).
If Start/Stop button C ha sn ot ye tb ee n
pressed, thi sc orrespond stot he key being
remove df rom the ignition.X
To switc hont he power supply: press
Start/Stop button C once.
The powe rs uppl yiss wi tched on. Yo uc an now
activate the windshield wipers, for example.
The powe rs uppl yiss wi tched off agai ni f:R
the driver's door is opene da ndR
yo up ress Start/Stop button C twice when
in thi sp ositionX
To switc hont he ignition: press Start/Stop
button C twice.
The ignition is switched on.
If yo up ress Start/Stop button C once when
in thi sp osit ion, the ignition is switched off
again.
Removing the Start/Sto pb uttonYo uc an remove the Start/Stop button from the
ignition lock and start the vehicl easn ormal
using the SmartKey. X
Remove Start/Stop button C from ignition
lock D .
Yo udon ot have to remove the Start/Stop but-
ton from the ignition lock when yo ul eave the
vehicle. Yo us hould, however, always take the
SmartKe yw it hy ou when leaving the vehicle. As
long as the Sma rtKe y isint h
e vehicle:R
the vehicl ec an 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 ar el ef tu nsupervised in the vehicle,
they could: R
open the doors ,t hu se ndangering other
people or roa du se rs.R
ge to ut and disrupt traffic. R
operate the vehicle's equipment.
Additionally, children could set the vehicl ei n
motion if, for example, they: R
release the parking brake. R
shifting the automatic transmission ou to f
park position P R
Star tt he engine.
There is ar is kofana ccident and injury.
Whe nl eavi ng the vehicle, always take the
SmartKe yw it hy ou and lock the vehicle. Never
leav ec hildren or animals unattended in the
vehicle. Alway sk ee pt he SmartKe yo ut of
reach of children.
G WARNING
Combustion engine se mi tp oiso nou se xhaust
gases such as carbo nm onoxide. Inhaling
thes ee xhaus tg as es lead stop oiso ning. There
is ar is koff ata li njury .T herefore neve rl eave
the engine running in enclose ds paces with-
ou ts uf ficient ventilation.
G WARNING
Flammabl em at erial si ntroduced through
environmenta li nfluence or by animals can
ignite if in contact with the exhaus ts ys tem or
parts of the engine tha th ea tu p. There is ar isk
of fire.
Carry ou tr egular checks to make sure that
ther ea re no flammabl ef oreig nm at erial si n
the engine compartment or in the exhaust
system.
During ac ol ds tart, the engine runs at higher
speed stoe nabl et he catalytic converter to116
Driving
Driving an dp arking

R
the syste md et ects moisture on the wind-
shiel dw he nt he air-conditioning syste mi s
switched on R
the battery's condition of charge is too low
Shiftin gt he transmission to position P does not
start the engine.
Deactivatin gora ct ivatin gt he ECO
start/sto pf unctionX
To deactivate: press ECO button C .
Indicato rl am p D goes out.X
To activate: press ECO button C .
Indicato rl am p D lights up.
If indicator lamp D is off ,t he ECO start/stop
functio nh as been deactivated manuall yora s
the resul tofa malfunction. The engine will then
not be switched off automaticall yw he nt he vehi-
cle stops. Driving 119
Dr ivi ng an dp arking Z

Problems with the engine Problem
Possible causes/consequences and P Solutions
The engine does not
start. The HOLD function or Distanc eP ilot DISTRONIC is activated.X
Deactivat et he HOLD function ( Y
page 148) or Distanc eP ilot
DISTRONIC ( Y
page 146).X
Try to start the engine again.
The engine does not
start. The starter motor
can be heard. R
There is am alfunction in the engine electronics.R
There is am alfunction 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 instrumen tc luster go out.X
Try to start the engine again ( Y
page 116). Avoid excessively long
and frequent attempt stos tart the engine as these will drain the
battery.
If the engine does not start after several attempts: X
Consult aq ualified 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 249).
If the engine does not start despite attempt stoj ump-start it:X
Consult aq ualified specialist workshop.
The starter motor was exposed to at hermal 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 aq ualified specialist workshop.
The engine is not running
smoothly and is misfir-
ing. There is am alfunction in the engine electronics or in am echanical
componen toft he 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 aq ualified specialist work-
shop.120
Driving
Driving and parking

cle from rolling away by applying the parking
brake. X
Appl yt he electri cp ar king brake.X
Shif tt he transmission to position P
( Y
page 123).X
With the SmartKey: turn the SmartKey to
position 0 in the ignition lock and remove it.
The immobilizer is activated. X
With KEYLESS-GO: press the KEYLESS-GO
Start/Stop button ( Y
page 115).
The engine stop sa nd al lt he indicator lamps in
the instrument cluster go out.
Whe nt he driver' sd oo risc losed, this corre-
sponds to SmartKey position 1 .W he nt he
driver' sd oo riso pen, this corresponds to
SmartKey position 0 ( Y
page 115).
The engine can be switched off while the vehicle
is in motio nb yp ressing and holding the Start/
Stop button for abou tt hree seconds. Thi sf unc-
tion operate si ndependently of the ECO start/
stop automatic engine switch-off function.
Electric parkin gb rake
General notes
G WARNING
If yo ul ea ve childre nu nsupervised in the vehi-
cle ,t hey could set it in motio nb y, for example:R
release the parking brake. R
shift the automatic transmission ou toft he
parking position P .R
star tt he engine.
In addition, they may operate vehicle equip-
ment and become trapped .T here is ar is ko f
an accident and injury.
Whe nl ea ving the vehicle ,a lway st ake the
SmartKey with yo ua nd lock the vehicle .N ever
leave childre nu nsupervised in the vehicle. The function of the electri cp ar king brake is
dependent on the on-board voltage .Ift he on-
board voltage is low or there is am alfunction in
the system, it may not be possible to appl yt he
released parking brake. X
If this is the case ,o nly park the vehicle on
level ground and secure it to prevent it rolling
away. X
Shif tt he automatic transmission to position
P .
It may not be possible to release an applied
parking brake if the on-board voltage is low or
there is am alfunction in the system. Contact a
qualified specialist workshop.
The electri cp ar king brake performs af unction
test at regula ri nterval sw hile the engine is
switched off. The sounds that can be heard while
this is occurring are normal.
Applyin gorr eleasin gm anually
X
To engage: push handle C .
Whe nt he electri cp ar king brake is engaged,
the I (USA only )o r $ (Canada only)
red indicator lamp lights up in the instrument
cluster.
The electri cp ar king brake can also be applied
whe nt he SmartKey is removed. X
To release: pull handle C .
The red I (USA only )o r $ (Canada
only )i ndicator lamp in the instrument cluster
goe so ut .
The electri cp ar king brake can only be released: R
if the SmartKey is in position 1 in the ignition
lock ( Y
page 115) or R
if the ignition wa ss witched on using the
Start/Stop button132
Parking
Drivin ga nd parking

In addition to driving style, the actual consump-
tion is affected by other factors, such as: R
load R
tire pressure R
cold start R
choice of route R
active electrical consumers
These factors are not include dint he ECO dis-
play.
An economical driving style specially requires
driving at moderate engine speeds.
Achieving ah igher valu eint he categories
"Acceleration" and "Constant": R
observe the gearshift recommendations. R
drive the vehicle in drive program C or E .
On long journeys at ac onstant speed ,e .g. on the
highway, only the outer area for "constant" will
change.
The ECO display summarizes the driving style
from the start of the journey to its completion.
Therefore, there are more marked changes in
the outer area satt he start of aj ourney. On lon-
ger journeys, there are fewer changes. For more
marked changes, perform am anua lr est
( Y
page 167).
For more information on the ECO display, see
( Y
page 166).
Braking
Important safety notes
G WARNING
If you shift down on as lippery road surface in
an attempt to increase the engine's braking
effect, the drive wheel sc ould lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on as lippery road surface.
Downhill gradients
! On long, steep gradients, you must reduce
the load on the brakes. To use engine braking,
shift to al owe rg ear in good time. This helps
you to avoid overheating the brakes and wear-
ing them out excessively. When making use of the engine braking
effect, it is possible that ad rive wheel may not
turn for some time, e.g. in the case of sud-
denly changing or slippery road surface con-
ditions. This could cause damage to the drive
train. This type of damage is not covered by
the Mercedes-Benz warranty.
Change into al owe rg ear in good time on long
and steep downhill gradients. This is especially
important if the vehicle is laden.
This also applies if you have activated cruise
control or Distance Pilo tD ISTRONIC.
Heavy and light loads
G WARNING
If you rest you rf oot on the brake peda lw hile
driving, the braking system can overheat. This
increases the stopping distance and can even
cause the braking system to fail .T here is a
risk of an accident.
Never use the brake peda lasaf ootrest. Never
depres st he brake peda la nd the accelerator
peda latt he same time.
! Depressing the brake peda lc onstantly
results in excessive and premature wea rt o
the brake pads.
If the brakes have been subjected to ah eavy
load ,don ot stop the vehicle immediately ,b ut
drive on for as hort while. This allows the airflow
to cool the brakes more quickly.
Wet roads If you have driven for al ong time in heavy rain
withou tb raking, there may be ad elayed 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 then have to depres st he brake peda lm ore
firmly .M aintai nag reater distance from the
vehicle in front.
After driving on aw et road or having the vehicle
washed, brake firmly whil ep aying attention to
the traffic conditions. This wil lw arm up the
brake discs, thereby drying them more quickly
and protecting them against corrosion.136
Driving tips
Driving and parking