2018 MERCEDES-BENZ SL CLASS battery

Problems with the SmartKey Problem
Possible causes/consequences and P Solutions
You can no longer lock or
unlock the vehicle using
the SmartKey. The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 68) and replace it if necessary
( Y
page 68).
If this does not work: X
Unlock ( Y
page 72) or lock ( Y
page 72) the vehicle using the
mechanical key.
There is interference from ap owerful source of radio waves.X
Unlock ( Y
page 72) or lock ( Y
page 72) the vehicle using the
mechanical key.
The SmartKey is faulty. X
Unlock ( Y
page 72) or lock ( Y
page 72) the vehicle using the
mechanical key. X
Have the SmartKey checked at aq ualified specialist workshop.
You can no longer lock or
unlock the vehicle using
KEYLESS-GO. KEYLESS-GO was deactivated. X
Reactivate KEYLESS-GO ( Y
page 65).
The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 68) and replace it if necessary
( Y
page 68).
If this does not work: X
Unlock ( Y
page 72) or lock ( Y
page 72) the vehicle using the
mechanical key.
There is interference from ap owerful source of radio waves.X
Unlock ( Y
page 72) or lock ( Y
page 72) the vehicle using the
mechanical key.
KEYLESS-GO is malfunctioning. X
Lock/unlock the vehicle using the remote control function of the
SmartKey. X
Have the vehicle and SmartKey checked at aq ualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function: X
Unlock ( Y
page 72) or lock ( Y
page 72) the vehicle using the
mechanical key. X
Have the vehicle and SmartKey checked at aq ualified specialist
workshop. SmartKey 69
Opening and closing Z

Problem
Possible causes/consequences and P Solutions
The engine cannot be
started using the Smart-
Key. The on-board voltage is too low. X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work: X
Check the starter battery and charge it if necessary ( Y
page 253).
or X
Jump-start the vehicle ( Y
page 253).
or X
Consult aq ualified specialist workshop.
The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. The vehicle is locked. X
Unlock the vehicle and try to start the vehicle again.
The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 68) and replace it if necessary
( Y
page 68).
If this does not work: X
Start your vehicle with the SmartKey in the ignition lock.
There is interference from ap owerful source of radio waves.X
Start your vehicle with the SmartKey in the ignition lock.
You have lost aS mart-
Key. X
Have the SmartKey deactivated at aq ualified specialist workshop.X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.
You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers. X
If necessary, have the locks changed as well.
The side windows cannot
be opened or closed
using the convenience
opening/closing fea-
ture. The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 68) and replace it if necessary
( Y
page 68).
Doors
Important safety notes
G WARNING
If children are left unsupervised in the vehicle,
they could: R
operate the vehicle's equipment. Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake R
shift the automatic transmission out of park
position P R
start the engine
There is ar isk of an accident and injury.
Never leave children or animals unattended in
the vehicle.70
Doors
Opening and closing

tion H .S imultaneousl yp ul lt he trunk li dh an -
dle.
The trunk is unlocked. X
Turn the mechanica lk ey back to position G
and remove it. X
Insert the mechanica lk ey into the SmartKey.
Emergenc yr elease fo rt he trunkYo uc an unlock the trunk li df ro mt he insid ew it h
the emergency release button.
X
Press emergency release button C briefly.
The trunk li du nlocks and opens.
The trunk li dc an be unlocke da nd opene dw it h
the trunk li de mergency release when the vehi-
cle is stationar yorw hile driving.
The trunk li de mergency release does not unlock
the trunk li dift he battery is disconnecte do r
discharged.
Trunk li de mergency release light:R
Emergency release button C flashe sf or
30 minute sa ft er the trunk li diso pe nedR
Emergency release button C flashe sf or
60 minute sa fter the trunk li disc losed
Side windows
Important safety notes
G WARNING
Whil eo pe ning the side windows ,b od yp ar ts
could become trapped between the side win-
do wa nd the door frame as the side window
moves .T here is ar is kofi njury.
Make sure tha tn obod yt ouche st he side win-
do wd ur in gt he opening procedure. If some- body become st rapped ,r elease the switch or
pull the switch to close the side windo wa gain .
G WARNING
Whil ec losing the side windows ,b od yp ar ts in
the closing area could become trapped .T here
is ar is kofi njury.
When closing make sure tha tnop ar ts of the
body ar eint he closing area .Ifs omebody
become st rapped ,r elease the switch or press
the switch to open the side windo wa gain .
G WARNING
If children operate the side windows they
could become trapped ,p ar ticularly if the ya re
left unsupervised .T here is ar is kofi njury.
When leaving the vehicle, always take the
SmartKe yw it hy ou and lock the vehicle. Never
leav ec hildren unsupervised in the vehicle.
Side windo wr eversin gf ea tureThe front side windows ar ee quippe dw it ha n
automatic reversing feature. If as olid object
blocks or restricts the upward movement of one
of the front side windows durin gt he closing
process, the side windo wo pe ns agai na ut omat-
ically. During the manua lc losing process, the
side windo wo nl yo pe ns agai na ut omatically
after the corresponding switch is released. How-
ever, the automatic reversing featur eiso nl ya n
ai da nd does not relieve yo uoft he responsibility
of paying attentio nw he nc losing as id ew in dow.
G WARNING
The reversing featur ed oe sn ot react:R
to soft, light and thi no bj ects ,e .g .s mall fin-
gers R
ove rt he last 1/6 in(4 mm) of the closing
movement R
durin gr esetting R
when closing the side windo wa gain man-
uall yi mm ediatel ya ft er automatic reversing
Thi sm eans tha tt he reversing featur ec annot
prevent someone being trapped in these sit-
uations. There is ar is kofi njury.74
Side windows
Openin ga nd closing

Problem
Possible causes/consequences and P Solutions
As ide window cannot be
closed because it is
blocked by objects, e.g.
leaves in the window
guide. X
Remove the objects. X
Close the side window.
As ide window cannot be
closed and you cannot
see the cause. If as ide window is obstructed during closing and reopens again
slightly: X
Immediately after the window blocks, pull the correspondin gs witch
again until the side window has closed.
The side window is closed with increased force.
If as ide window is obstructed again during closing and reopens again
slightly: X
Immediately after the window blocks, pull the correspondin gs witch
again until the side window has closed.
The side window is closed without the automatic reversing feature.
The side windows cannot
be opened or closed
using the convenience
opening/closing fea-
ture. The SmartKey battery is discharged or nearly discharged. X
Check the SmartKey battery ( Y
page 68) and replace it if necessary
( Y
page 68).
Roof
Important safety notes
G WARNING
If you do not fully open/close the soft top, the
soft-top hydraulics depressurize after as hort
time. This causes the soft top to lower unex-
pectedly and may cause you or others to be
trapped. There is ar isk of injury.
Always open or close the soft top completely.
G WARNING
Closing the roof manually is ac omplicated
and technically demanding procedure, which
requires al ot of strength. You or others can
become trapped. There is ar isk of injury.
Only have the soft top closed manually at a
qualified specialist workshop.
! Never sit on the rear shelf or store heavy
object st here. You will otherwise damage the
roof and the rear shelf of your vehicle. ! Do not forget that the weather can change
abruptly. Make certain that the roof is closed
when you leave the vehicle. The vehicle elec-
tronics can be damaged if water enters the
vehicle interior.
! When opening and closing the roof, make
sure that: R
there is sufficient clearance, as the roof
swings upwards. R
there is sufficient clearance behind the
vehicle, as the trunk lid swings backwards
beyond the bumper. R
the trunk is only loaded to below the trunk
partition. R
the trunk partition is not pushed up by the
load. R
the trunk partition is closed. R
the trunk lid is closed. R
the outside temperature is above 5‡
(

This could result in burns in the immediate
vicinit yoft he air vents. There is ar isk of injury.
Reduce the heater output before it becomes
too hot.
The AIRSCARF function warms the head and
neck area of vehicle occupant sw ith warm air.
The warm air flows out of the holes in the head
restraints.
The three red indicator lamps in the button indi-
cate the heating level you have selected. X
Ensure that the SmartKey is in position H in
the ignition lock. X
To switch on: press button C .
Three red indicator lamps in the button light
up. The blower start supa fter ap reheating
phase of seven seconds. X
Press button C repeatedly until the desired
heating level is set. X
To switch off: press button C repeatedly
until all the indicator lamps go out.
i The blower continues runnin gf or seven sec-
onds to cool down the heating elements.
i If the battery voltage is too low, AIRSCARF
may switch off.
Problems with AIRSCARF AIRSCARF has switched off prematurely or will
not switch on. The vehicle's electrical system
voltage is too low because too many electrical
consumer sa re switched on.X
Switch off electrical consumer st hat you do
not need, such as the rear window defroster
or interior lighting. X
Switch on AIRSCARF again. Steering wheel
Important safety notes
G WARNING
You could lose control of your vehicle if you do
the following while driving: R
adjust the driver's seat, head restraint,
steerin gw heel or mirrors R
fasten the seat belt
There is ar isk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt
before starting the engine.
G WARNING
Children could injure themselves if they
adjust the steerin gw heel. There is ar isk of
injury.
When leaving the vehicle, alway st ake the
SmartKey with you and lock the vehicle. This
also applies to mobile phones if the "Digital
Car Key in smartphone" function is activated
via the Mercedes me connect web app. Never
leave children unsupervised in the vehicle.
The electrically adjustable steerin gw heel can
still be adjusted when there is no SmartKey in
the ignition lock.
Adjusting the steering wheel man-
ually
G WARNING
If the steerin gw heel is unlocked while the
vehicle is in motion ,itc ould change position
unexpectedly. This could cause you to lose
control of the vehicle. There is ar isk of an
accident.
Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion.88
Steering wheel
Seats, steering wheel and mirrors

The daytime runnin gl amps improve the visibility
of your vehicle during the day. To do this, the
daytime runnin gl amps function must be
switched on using the on-board computer
( Y
page 172).
If the engine is runnin ga nd you turn the light
switch to ` or X ,t he manual settings
take precedenc eo ver the daytime running
lamps.
Low-beam headlamps
G WARNING
When the light switch is set to X ,t he 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 ar isk 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 ap articularly useful function in the event
of rain and fog. X
To switch on the low-beam headlamps:
turn the SmartKey to position H in the igni-
tion lock or start the engine. X
Turn the light switch to X .
The green X indicator lamp in the instru-
ment cluster lights up.
Rear fog lamp
The rear fog lamp improves visibility of your
vehicle for the traffic behind in the event of thick
fog. Please take not eoft he country-specific
regulations for the use of rear fog lamps. X
To switch on the rear fog lamp: turn the
SmartKey to position H in the ignition lock or
start the engine. X
Turn the light switch to X or X .X
Press the ^ button.
The yellow ^ indicator lamp in the instru-
ment cluster lights up. X
To switch off the rear fog lamp: press the
^ button.
The yellow ^ indicator lamp in the instru-
ment cluster goes out. Parking lamps
! If the battery charge is very low, the parking
lamps or standin gl amps are automatically
switched off to enable the next engine start.
Always park your vehicle safely and in aw ell lit
area, in accordanc ew ith the relevant legal
stipulations. Avoid using the ` parking
lamps over ap eriod of several hours. If pos-
sible, switch on the right-hand d or left-
hand c standin gl amps.X
To switch on: turn the light switch to ` .
The green ` indicator lamp in the instru-
ment cluster lights up.
Standing lamps Switching on the standin gl amps ensures the
corresponding side of the vehicle is illuminated. X
To switch on the standing lamp s: the
SmartKey is not in the ignition lock or it is in
position

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.
Activating/deactivating X
Turn the SmartKey to position H in the igni-
tion lock ( Y
page 116).X
To activate: 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 deactivate: 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 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

i If you activate the residual heat function at
high temperatures, only the ventilation wil lb e
activated. The blower runs at mediu ms peed.X
To deactivate: press the K or V but-
ton.
The indicator lamp in the K or V button
goes out.
Residua lh eat is deactivated automatically:R
after approximately 30 minutes R
when the ignition is switched on R
if the battery voltage drops
Setting the air vents
Important safety notes
G WARNING
Very hot or very cold air can flow from the air
vents. This could resul tinb urns or frostbite in
the immediate vicinity of the air vents. There
is ar isk of injury.
Make sure that all vehicle occupants always
maintain as ufficient distance to the air out-
lets. If necessary ,r edirect the airflow to
another area of the vehicle interior.
G WARNING
When AIRSCARF is switched on, very hot air
can flow from the vents in the head restraints.
This could resul tinb urns in the immediate
vicinity of the air vents. There is ar isk of injury.
Reduce the heater outpu tb efore it becomes
too hot.
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 grill eont he hood and in the
engine compartment on the front-passenger
side free of blockages, such as ice, snow or
leaves. R
never cover the air vents or air intake grilles in
the vehicle interior.
i You can move the adjusters for the air vents
verticall yorh orizontally to set the direction of
the airflow. i For optimal climate control in the vehicle,
open the air vents completely and set the
adjusters to the central position.
Setting the center air vents X
To open the center air vents: turn the
adjuster in one of center air vents C counter-
clockwise. X
To close the center air vents: turn the
adjuster in one of center air vents C clock-
wise until it engages.
Setting the side air vents
C
Side window defroster vent
D
Side air vent X
To open as ide air vent: turn the adjuster in
the side air vent D to the left.X
To close as ide air vent: turn the adjuster in
the side air vent D to the right until it
engages.Setting the air vents 113
Climate control Z