2018 MERCEDES-BENZ SL ROADSTER radiator

ProblemPossible causes/consequences andMSolutions
The coolant temperature
gauge shows a value
above 248 ‡ (120 †).
The coolant warning
lamp may also be on and
a warning tone may
sound.The coolant level is too low. The coolant is too hot and the engine is no
longer being cooled sufficiently.
XStop as soon as possible and allow the engine and the coolant to
cool down.
XCheck the coolant level (Ypage 260). Observe the warning notes
as you do so and add coolant if necessary.
If the coolant level is correct, the engine radiator fan may be faulty. The
coolant is too hot and the engine is no longer being cooled sufficiently.
XAt coolant temperatures below 248 ‡(120 †), drive to the nearest
qualified specialist workshop.
XAvoid heavy loads on the engine as you do so, e.g. driving in moun-
tainous terrain and stop-and-go traffic.
DYNAMIC SELECT button (all vehicles
except Mercedes-AMG vehicles)
Use the DYNAMIC SELECT button to change the
drive program. Depending on the drive program
selected the following vehicle characteristics
will change:
Rthe drive (engine and transmission manage-
ment)
Rthe suspension
Rthe steering
Rthe curve tilting function (vehicles with Active
Body Control)
Rthe control thresholds of ESP®
Each time you start the engine with the Smart-
Key or the Start/Stop button, drive program Cis
activated. For further information about starting
the engine, see (
Ypage 123).
XPress DYNAMIC SELECT button :as many
times as necessary until the desired drive
program is selected.
The selected drive program appears in the
multifunction display. After a short period of
time, the display goes out and the symbol for the selected drive program appears.
In addition, the current drive program settings
are displayed briefly in the multimedia systemdisplay.
iIn a few countries, the ECO start/stop func-
tion is deactivated at the factory due to the
available fuel grade. In this case, the ECO
start/stop function is not available in any
drive program, regardless of the display in the
multimedia system display.
Available drive programs:
C ComfortComfortable and economi-
cal driving characteristics
SSportSporty driving characteris-
tics
S+ Sport PlusParticularly sporty driving
characteristics
IIndividualIndividual settings
128DYNAMIC SELECT button (all vehicles except Mercedes-AMG vehicles)
Driving and parking

this is that ATTENTION ASSIST still detects typ-ical indicators of fatigue or increasing lapses in
concentration.
Vehicles with COMAND: if a warning is issued
in the multifunction display, a service station
search is performed in COMAND. You can select
a service station and navigation to this service
station will then begin. This function can be acti- vated and deactivated in COMAND.
Active Driving Assistance package
General notes
The Active Driving Assistance package consists
of Distance Pilot DISTRONIC (Ypage 151),
Steering Pilot and Stop&Go Pilot, Active Blind
Spot Assist (
Ypage 179 )and Active Lane Keep-
ing Assist (Ypage 181).
Active Blind Spot Assist
General notes
Active Blind Spot Assist monitors the areas on
either side of the vehicle that are not directly
visible to the driver with two lateral, rear-facing
radar sensors. A warning lamp lights up in the
exterior mirrors and draws your attention to
vehicles detected in the monitored area. If you
then switch on the corresponding turn signal to
change lane, you will also receive an optical and
audible warning. If a risk of lateral collision is
detected, corrective braking may help you avoid
a collision. Before a course-correcting brake
application, Active Blind Spot Assist evaluates
the space in the direction of travel and at the
sides of the vehicle. For this, Active Blind Spot
Assist uses the forward-facing radar sensors.
Active Blind Spot Assist supports you from a
speed of approximately 20 mph (30 km/h).
Important safety notes
Active Blind Spot Assist is only an aid and is not
a substitute for attentive driving.
GWARNING
Active Blind Spot Assist does not react to:
Rvehicles overtaken too closely on the side,
placing them in the blind spot area
Rvehicles which approach with a large speed
differential and overtake your vehicle
As a result, Active Blind Spot Assist may nei-
ther give warnings nor intervene in such sit-
uations. There is a risk of an accident.
Always observe the traffic conditions care-
fully, and maintain a safe lateral distance.
iUSA only: This device has been approved by
the FCC as a "Vehicular Radar System". The
radar sensor is intended for use in an auto-
motive radar system only. Removal, tamper-
ing, or altering of the device will void any war-
ranties, and is not permitted by the FCC. Do
not tamper with, alter, or use in any non-
approved way.
Any unauthorized modification to this device
could void the user's authority to operate the
equipment.
iCanada only: This device complies with
RSS-210 of Industry Canada. Operation is
subject to the following two conditions:
1. This device may not cause interference,
and
2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the device
will void any warranties, and is not permitted. Do not tamper with, alter, or use in any non-
approved way.
Any unauthorized modification to this device
could void the user's authority to operate the
equipment.
Radar sensors
The radar sensors for Active Blind Spot Assist
are integrated in the rear bumper and in the
radiator trim. Make sure that the bumpers and
radiator trim are free from dirt, ice and slush.
The rear sensors must not be covered, for exam-
ple by cycle racks or overhanging cargo. Fol-
lowing a severe impact or in the event of damage
to the bumpers, have the function of the radar
sensors checked at a qualified specialist work-
shop. Active Blind Spot Assist may otherwise no
longer work properly.
Monitoring area
GWARNING
Active Blind Spot Assist does not detect all
traffic situations and road users. There is a
risk of an accident.
Driving systems179
Driving an d parking
Z

Engine
Display messagesPossible causes/consequences andMSolutions
?
CheckCoolantLevelSee Operator's Man‐ual
The coolant level is too low.
!Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
XAdd coolant, observing the warning notes before doing so
(Ypage 260).
XIf you need to add coolant more often than usual, have the engine
coolant system checked at a qualified specialist workshop.
?The fan motor is malfunctioning.
XIf the coolant temperature gauge is below the Hmarking
(Ypage 186), drive on to the next qualified specialist workshop.
XAvoid heavy loads on the engine as you do so, e.g. driving in moun-
tainous terrain and stop-and-go traffic.
?
Coolant Too HotStop Vehicle TurnEngine Off
The coolant is too hot.
A warning tone also sounds.
GWARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to catch
fire.
Steam from the overheated engine can also cause serious burns which
can occur just by opening the hood.
There is a risk of injury.
XPull over and stop the vehicle safely and switch off the engine, pay- ing attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 142).
XLeave the vehicle and keep a safe distance from the vehicle until the
engine has cooled down.
XMake sure that the air supply to the engine radiator is not blocked,
e.g. by snow, slush or ice.
XDo not start the engine again until the display message goes out and
the coolant temperature gauge is below the Hmarking
(
Ypage 186). Otherwise, the engine could be damaged.
XPay attention to the coolant temperature gauge, observing the
warning notes (Ypage 260).
XIf the temperature increases again, visit a qualified specialist work-
shop immediately.
Under normal operating conditions and at the correct coolant level,
the coolant temperature gauge may rise to the Hmarking
(
Ypage 186).
Display messages213
On-board computer and displays
Z

Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
?NThe red coolant warning lamp comes on while the engine is running.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may be blocked or
the electric engine radiator fan may be defective.
The coolant is too hot and the engine is no longer being cooled sufficiently.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 142).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 260).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
XDo not start the engine again until the coolant temperature gauge is below the H
marking (Ypage 186). Otherwise, the engine could be damaged.
XDrive to the nearest qualified specialist workshop.
XAvoid heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-and-go traffic.
?N The red coolant warning lamp comes on while the engine is running.
The coolant temperature gauge has exceeded the Hmarking (
Ypage 186). The
airflow to the engine radiator may be blocked or the coolant level may be too low.
GWARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive when your engine is overheated. This can cause some fluids which
may have leaked into the engine compartment to catch fire.
Steam from the overheated engine can also cause serious burns which can occur
just by opening the hood.
There is a risk of injury.
XObserve the additional display messages in the multifunction display.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 142).
XLeave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
XCheck the coolant level and add coolant, observing the warning notes
(Ypage 260).
XIf you have to add coolant frequently, have the engine cooling system checked.
XMake sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
Warning and indicator lamps233
On-board computer and displays
Z

Engine compartment
Hood
Important safety notes
GWARNING
If the hood is unlatched, it may open up when the vehicle is in motion and block your view.
There is a risk of an accident.
Never unlatch the hood while driving. Before
every trip, ensure that the hood is locked.
GWARNING
When opening and closing the hood, it may
suddenly fall into the closed position. There is a risk of injury to persons within range of
movement of the hood.
Open and close the hood only when no one is
within its range of movement.
GWARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
GWARNING
The engine compartment contains moving
components. Certain components, such as
the radiator fan, may continue to run or start
again suddenly when the ignition is off. There is a risk of injury.
If you need to do any work inside the engine
compartment:
Rswitch off the ignition
Rnever reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area
Rremove jewelry and watches
Rkeep items of clothing and hair, for exam-
ple, away from moving parts
Opening the hood
GWARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the components described in the
following.
GWARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood.
!Make sure that the windshield wipers are
not folded away from the windshield. You
could otherwise damage the windshield wip-
ers or the hood.
XMake sure that the windshield wipers are
turned off.
XPull release lever :on the hood.
The hood is released.
258Engine compartment
Maintenance and care

XReachint oth egap, pull hoo dcatch handle ;
up and lift hoo d:.
If you lift th ehoo dby approximately 15 in
(40 cm), th ehoo dis opened and held open
automatically by th egas-filled strut .
Closing the hood
XLowerth ehoo dand let it fall from aheight of
approximately 8in (20 cm).
XChec kthat th ehoo dhas engage dproperly.
If th ehoo dcan be raised slightly, it is no t
properly engaged. Open it again and close it
wit h a littlemor eforce .
Engine oil
Notes on the oil level
Dependin gon your driving style, th evehicl e
consumes up to 0. 9US qt (0.8 liters )of oi lpe r
60 0mile s(1,000 km). Th eoi lcons umption may
be higher than th iswhen the veh icle isnew or if
you frequently drive at high engine speeds.
Dependin g on the engine, the oil dipstick may be
in adiff erent location.
When checking the oil leve l:
Rpark the vehicleon a level surface
Rthe engine should be switched off for approx-
imately five minutes ifthe engine isat normal
operating temperature
Rif the engine isnot at normal operating tem-
perature, e.g. ifthe engine was only started
brie fly,wait about 30 minute sbefore carrying
out the measurement
Checking the oil level using the oil dip-
stick
GWARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Only touch the following components descri-
bed.
Example
XPull out oil dipstick :.
XWipe off oil dipstick :.
XSlowly slide oil dipstick :into the guide tube
to the stop, and take it out again.
If the level is between MIN mark =and MAX
mark ;, the oil level is correct.
XIf the oil level has dropped to MIN mark =or
below, add 1.1 US qt (1.0 liter) of engine oil.
Adding engine oil
GWARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the components described in the
following.
Engine compartment259
Maintenance and care
Z

GWARNING
If engine oil comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Make sure that engine oil is not spilled next to
the filler neck. Let the engine cool down and
thoroughly clean the engine oil off the com-
ponents before starting the engine.
HEnvironmental note
When adding oil, take care not to spill any. If
oil enters the soil or waterways, it is harmful to
the environment.
!Use only engine oils and oil filters that are
approved for vehicles with a service system. A list of the engine oils and oil filters that have
been tested and approved in accordance with
Mercedes-Benz Specifications for Service
Products is available at any authorized
Mercedes-Benz Center.
The following cause engine failure or damage
to the exhaust system:
RUse of engine oils and oil filters that have
not been expressly approved for the service
system
RReplacement of engine oil and oil filter after
the replacement interval specified by the
service system has expired
RUse of engine oil additives
!Do not add too much oil. If the oil level is
above the "max" mark on the dipstick, too
much oil has been added. This can lead to
damage to the engine or the catalytic con-
verter. Have excess oil siphoned off.
Example: engine oil cap
XTurn cap :counter-clockwise and remove it.
XAdd engine oil.
If the oil level is at or below the MIN mark on
the oil dipstick, add 1.1 US qt (1.0 liter) of
engine oil.
XReplace cap :on the filler neck and turn
clockwise.
Ensure that the cap locks into place securely.
XCheck the oil level again with the oil dipstick
(Ypage 259).
Further information on engine oil (
Ypage 314).
Checking and adding other service
products
Checking coolant level
GWARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the components described in the
following.
GWARNING
The cooling system is pressurized, particularly
when the motor is warm. If you open the cap,
you could be scalded if hot coolant sprays out.
There is a risk of injury.
Let the engine cool down before you open the
cap. Wear gloves and eye protection. Slowly
open the cap to relieve pressure.
Example
260Engine compartment
Maintenance and care

XPark the vehicle on a level surface.
Only check the coolant level when the vehicleis on a level surface and the engine has cooled
down.
XTurn the SmartKey to position 2in the igni-
tion lock (Ypage 122).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (
Ypage 122).
XCheck the coolant temperature gage in the
multifunction display.
The coolant temperature must be below
158 ‡ (70 †).
XTurn the SmartKey to position u
(Ypage 122) in the ignition lock.
XSlowly turn cap ;half a turn counter-clock-
wise to allow excess pressure to escape.
XTurn cap ;further counter-clockwise and
remove it.
If the coolant is at the level of marker bar =
in the filler neck when cold, there is enough
coolant in coolant expansion tank :.
If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar =in the fuel filler
neck when warm, there is enough coolant in
expansion tank :.
XIf necessary, add coolant that has been tested
and approved by Mercedes-Benz.
XReplace cap;and turn it clockwise as far as
it will go.
Further information on coolant (
Ypage 315).
Windshield washer system
GWARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the components described in the
following.
GWARNING
Windshield washer concentrate could ignite if it comes into contact with hot engine compo-
nents or the exhaust system. There is a risk of
fire and injury.
Make sure that no windshield washer con-
centrate is spilled next to the filler neck.
Example
XTo open: pull cap:upwards by the tab.
XAdd the premixed washer fluid.
XTo close: press cap :onto the filler neck
until it engages.
If the washer fluid level drops below the recom-
mended minimum fluid level of 1 US qt (1 liter),
a message appears in the multifunction display
prompting you to add washer fluid (
Ypage 225).
Further information on windshield washer fluid/
antifreeze (
Ypage 316).
Overview of the engine compartment
Example engine
:
Oil dipstick
;Brake fluid reservoir
=Engine oil cap
?Coolant expansion tank
AWasher fluid reservoir
Overview of the engine compartment261
Maintenance and care
Z