engine overheat MERCEDES-BENZ SL-Class 2016 R231 Owner's Manual

Driving
Important safet ynotes
GWARNING
Objects in th edriver's footwell can restric tth e
peda ltrave lor obstruct adepressed pedal.
The operatin gand road safet yof th evehicle is
jeopardized. There is aris kof an accident.
Mak esur ethat all objects in th evehicle are
stowed correctly, and that they canno tente r
th edriver's footwell. Install th efloormat s
securely and as specifie din order to ensur e
sufficien tclearanc efo rth epedals. Do no tuse
loose floormat sand do no tplac efloormat son
to pof on eanother.
GWARNING
Unsuitable footwear can hinder correc tusag e
of th epedals, e.g. :
Rshoes withthic ksoles
Rshoes wit hhig hheels
Rslipper s
There is aris kof an accident.
Wear suitable footwear to ensur ecorrec t
usag eof th epedals.
GWARNING
If you switch of fth eignition whil edriving,
safety-relevant function sare only available
wit hlimitations, or no tat all. Thi scould affect,
fo rexample, th epowe rsteerin gand th ebrake
boostin geffect .You will require considerably
more effort to steer and brake .There is aris k
of an accident.
Do no tswitch of fth eignition whil edriving.
GWARNING
If th eparking brake has no tbee nfull y
release dwhen driving, th eparking brake can :
Roverheat and cause afir e
Rlos eits hol dfunction .
There is aris kof fir eand an accident. Release
th eparking brake full ybefor edrivin goff.
!Do no twarm up th eengin ewit hth evehi-
cl e stationary. Drive of fimmediately. Avoid
hig hengin espeeds and drivin gat full throt-
tl e until th eengin ehas reached it soperat -
in g temperature .
Only shift th eautomatic transmissio nto
th edesire ddrive position when th evehicle
is stationary.
Where possible, avoid spinnin gth edrive
wheels when pulling away on slipper y
roads. You could otherwise damage th e
drive train .
!Mercedes-AMG vehicles :at low engin e
oil temperature sbelo w68 ‡(+2 0†), th e
maximum engin espeed is restricte din
order to protect th eengine. To protect th e
engin eand maintain smoot hengin eoper-
ation ,avoid drivin gat full throttle when th e
engin eis cold.
SmartKe ypositions
SmartKe y
gTo removeth eSmartKey
1Powe rsupply fo rsom econsumers ,suc h
as th ewindshield wipers
2Ignition (power supply fo rall consumers )
and drive position
3To start th eengin e
iThe SmartKey can be turned in th eigni-
tion loc keve nif it is no tth ecorrec tSmart -
Key fo rth evehicle. The ignition is no t
switched on .The engin ecanno tbe started.
Driving151
Driving and parking
Z

RAccel.(evaluation of all acceleration pro-
cesses):
-The bar fills up: moderate acceleration,
especially at higher speeds
-The bar empties: sporty acceleration
RConstant(assessment of driving behavior
at all times):
-The bar fills up: constant speed and
avoidance of unnecessary acceleration
and deceleration
-The bar empties: fluctuations in speed
RCoasting(assessment of all deceleration
processes):
-The bar fills up: anticipatory driving,
keeping your distance and early release
of the accelerator. The vehicle can coast
without use of the brakes.
-The bar empties: frequent braking
iAn economical driving style specially
requires driving at moderate engine
speeds.
To achieve a higher value in the categories
Acceleration
and Constant:
Robserve the gearshift recommendations.
Rdrive in drive program E.
iOn long journeys at a constant speed, e.g.
on the highway, only the bar for Constant
will change.
iThe ECO display summarizes the driving
characteristics from the start of the journey
to its completion. For this reason, the bars
change dynamically at the beginning of the
journey. On longer journeys, there are
fewer changes. For more dynamic changes,
carry out a manual reset.
For more information on the ECO display, see
(
Ypage 226).
Brakes
Important safety notes
GWARNING
If you shift down on a slippery road surface in an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface.
Downhill gradients
!On long, steep gradients, you must
reduce the load on the brakes. To use
engine braking, shift to a lower gear in good
time. This helps you to avoid overheating
the brakes and wearing them out exces-
sively.
When making use of the engine braking
effect, it is possible that a drive wheel may
not turn for some time, e.g. in the case of
suddenly changing or slippery road surface
conditions. This could cause damage to the
drive train. This type of damage is not cov-
ered by the Mercedes-Benz warranty.
Change into a lower gear in good time on long
and steep downhill gradients. This is espe-
cially important if the vehicle is laden.
This also applies if you have activated cruise
control, SPEEDTRONIC or DISTRONIC PLUS.
Heavy and light loads
GWARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time.
176Driving tips
Driving and parking

and drive at a speed to suit the prevailing
weather conditions.
You should pay special attention to road con-
ditions when temperatures are around freez-
ing point.
For more information on driving with snow
chains, see (
Ypage 571).
For more information on driving with summer
tires, see (
Ypage 570).
Observe the notes in the "Winter operation"
section (
Ypage 570).
Driving systems
Cruise Control
General notes
Cruise control maintains a constant road
speed for you. It brakes automatically in order
to avoid exceeding the set speed. On long and
steep downhill gradients, especially if the
vehicle is laden, you must select a lower gear
in good time. By doing so, you will make use of
the braking effect of the engine. This relieves
the load on the brake system and prevents
the brakes from overheating and wearing too
quickly.
Use cruise control only if road and traffic con-
ditions make it appropriate to maintain a
steady speed for a prolonged period. You can
store any road speed above 20 mph
(30 km/h).
Important safety notes
If you fail to adapt your driving style, cruise
control can neither reduce the risk of an acci-
dent nor override the laws of physics. Cruise
control cannot take into account the road,
traffic and weather conditions. Cruise control
is only an aid. You are responsible for the dis-
tance to the vehicle in front, for vehicle speed,
for braking in good time and for staying in
lane. Do not use cruise control:
Rin road and traffic conditions which do not
allow you to maintain a constant speed e.g.
in heavy traffic or on winding roads
Ron slippery road surfaces. Braking or accel-
erating could cause the drive wheels to lose
traction and the vehicle could then skid
Rwhen there is poor visibility, e.g. due to fog,
heavy rain or snow
If there is a change of drivers, advise the new
driver of the speed stored.
Cruise control lever
Cruis econtrol leve r
:
To store the current speed or a higher
speed
;To store the current speed or call up the
last stored speed
=To store the current speed or a lower
speed
?To deactivate cruise control
When you activate cruise control, the stored
speed is shown in the status indicator of the
multifunction display:
RUSA only: e.g. CRUISE 55 Miles
RCanada only: e.g. ¯90 Km/h
180Driving systems
Driving and parking

XTo adjust the set speed in 1 mph incre-
ments (1 km/h increments):briefly
press the cruise control lever up :to the
pressure point for a higher speed or
down ;for a lower speed.
Every time the cruise control lever is
pressed up or down, the last speed stored
is increased or reduced.
XTo adjust the set speed in 5 mph incre-
ments (10 km/h increments): briefly
press the cruise control lever up :past
the pressure point for a higher speed or
down ;for a lower speed.
Every time the cruise control lever is
pressed up or down, the last speed stored
is increased or reduced.
iCruise control is not deactivated if you
depress the accelerator pedal. For exam-
ple, if you accelerate briefly to overtake,
cruise control adjusts the vehicle's speed
to the last speed stored after you have fin- ished overtaking.
Deactivating cruise control
Cruise control lever
There are several ways to deactivate cruise
control:
XBriefly press the cruise control lever for-
wards :.
or
XBrake. Cruise control is automatically deactivated if:
Ryou engage the electric parking brake
Ryou are driving at less than 20 mph
(30 km/h)
RESP®intervenes or you deactivate ESP®
Ryou shift the transmission to position
N
while driving
If cruise control is deactivated, you will hear a
warning tone. You will see the Cruise Con‐
trol Offmessage in the multifunction dis-
play for approximately five seconds.
iWhen you switch off the engine, the last
speed stored is cleared.
DISTRONIC PLUS
General notes
DISTRONIC PLUS regulates the speed and
automatically helps you maintain the dis-
tance to the vehicle detected in front.
DISTRONIC PLUS brakes automatically so
that the set speed is not exceeded.
On long and steep downhill gradients, espe-
cially if the vehicle is laden, you must select a
lower gear in good time. By doing so, you will
make use of the braking effect of the engine.
This relieves the load on the brake system and prevents the brakes from overheating and
wearing too quickly.
If a slower-moving vehicle is detected in front,
DISTRONIC PLUS brakes your vehicle. It
maintains the preset distance to the vehicle in
front.
If DISTRONIC PLUS detects that there is a risk
of a collision, you will be warned visually and
acoustically. DISTRONIC PLUS cannot pre-
vent a collision without your intervention. An
intermittent warning tone will then sound and
the distance warning lamp will light up in the
instrument cluster. Brake immediately in
order to increase the distance to the vehicle
in front or take evasive action provided it is
safe to do so.
182Driving systems
Driving an d parking

The segments between the speed of the
vehicle in front and the stored speed light
up.
Tachometer
!
Do not drive in the overrevving range, as
this could damage the engine.
The red band in the tachometer indicates the
engine's overrevving range.
The fuel supply is interrupted to protect the
engine when the red band is reached.
Outside temperature display
You should pay special attention to road con-
ditions when temperatures are around freez-
ing point.
Bear in mind that the outside temperature
display indicates the temperature measured
and does not record the road temperature.
The outside temperature display is in the mul-
tifunction display (
Ypage 224).
A change in the outside temperature is shown
in the multifunction display after a delay.
Coolant temperature display
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.
!A display message is shown if the coolant
temperature is too high.
If the coolant temperature is over 248 ‡
(120 †), do not continue driving. The
engine will otherwise be damaged. The coolant temperature gauge is in the
instrument cluster on the right-hand side
(
Ypage 41).
Under normal operating conditions and with
the specified coolant level, the coolant tem-
perature may rise to 248 ‡ (120 †).
Operating the on-board computer
Overview
:Multifunction display
;Switches on the Voice Control System
(see the separate operating instructions)
=Right control panel
?Left control panel
ABack button
XTo activate the on-board computer: turn
the SmartKey to position 1in the ignition
lock.
You can control the multifunction display and
the settings in the on-board computer using
the buttons on the multifunction steering
wheel.
Displays and operation223
On-board computer and displays
Z

Display messagesPossible causes/consequences andMSolutions
?
CoolantToo Hot
Sto pVehicl eTur n
Engine Off
The coolan tis to ohot .
A warnin gtone also sounds.
GWARNIN G
Do notdrive when your engin eis overheated. This can caus esom e
fluids whic hmay hav eleaked into th eengin ecompartmen tto
catch fire.
Steam from th eoverheated engin ecan also caus eserious burn s
whic hcan occur jus tby openin gth ehood.
There is aris kof injury.
XPull ove rand stop th evehicl esafely and switch of fth eengine,
payin gattention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 171).
XLeaveth evehicl eand keep asaf edistanc efrom th evehicl euntil
th eengin ehas cooled down .
XMakesur ethat th eair supply to th eengin eradiato ris no t
blocked, e.g. by snow, slus hor ice .
XDo no tstart th eengin eagain until th edisplay message goe sout
and th ecoolan ttemperature is belo w24 8 ‡ (120†). Other -
wise ,th eengin ecould be damaged.
XPay attention to th ecoolan ttemperature display.
XIf th etemperature increase sagain ,visit aqualified specialist
workshop immediately.
Under normal operating condition sand wit hth especified coolan t
level, th ecoolan ttemperature may ris eto 24 8 ‡(120†).
#
SeeOperator' sMan‐
ual
The battery is no tbein gcharged.
A warnin gtone also sounds.
Possibl ecauses are:
Radefective alternato r
Ratorn poly-V-belt
Ramalfunction in th eelectronics
!Do no tcontinue driving. The engin ecould otherwise overheat .
XPull overand stop th evehicl esafely and switch of fth eengine,
payin gattention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 171).
XConsult aqualified specialist workshop .
256Display messages
On-board computer and displays

ProblemPossible causes/consequences andMSolutions
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.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 malfunc-
tioning.
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 171).
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 539).
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 is
below 248‡(120 †). Otherwise, the engine could be damaged.
XDrive to the nearest qualified specialist workshop.
XAvoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic.
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.The coolant temperature has exceeded 248 ‡ (120 †). The air-
flow 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 171).
Warning and indicator lamps279
On-board computer and displays
Z

Useful information
i
This Operator's Manual describes all
models and all standard and optional equip-
ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
iRead the information on qualified special-
ist workshops (
Ypage 34).
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
wipers or the hood.
536Engine compartment
Maintenance and care

Select an engine oil with an SAE classification
(viscosity) suitable for the prevailing outside
temperatures. The table shows you which
SAE classifications are to be used. The low-
temperature characteristics of engine oils
can deteriorate significantly, e.g. as a result
of aging, soot and fuel deposits. It is therefore
strongly recommended that you carry out reg-
ular oil changes using an approved engine oil
with the appropriate SAE classification.
Brake fluid
GWARNING
The brake fluid constantly absorbs moisture
from the air. This lowers the boiling point of
the brake fluid. If the boiling point of the brake
fluid is too low, vapor pockets may form in the
brake system when the brakes are applied
hard. This would impair braking efficiency.
There is a risk of an accident.
You should have the brake fluid renewed at
the specified intervals.
When handling brake fluid, observe the
important safety notes on service products
(
Ypage 603).
The brake fluid change intervals can be found
in the Maintenance Booklet.
Only use brake fluid approved by Mercedes-
Benz in accordance with MB-Freigabe or MB-
Approval 331.0.
Information about approved brake fluid can
be obtained at any qualified specialist work-
shop or on the Internet at
http://bevo.mercedes-benz.com.
iHave the brake fluid regularly replaced at
a qualified specialist workshop and the
replacement confirmed in the Maintenance
Booklet.
Coolant
Important safety notes
GWARNING
If antifreeze comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Let the engine cool down before you add anti-
freeze. Make sure that antifreeze is not spilled
next to the filler neck. Thoroughly clean the
antifreeze from components before starting
the engine.
!Only add coolant that has been premixed
with the desired antifreeze protection. You
could otherwise damage the engine.
Further information on coolants can be
found in the Mercedes-Benz Specifications
for Service Products, MB BeVo 310.1, e.g.
on the Internet at
http://bevo.mercedes-benz.com. Or con-
tact a qualified specialist workshop.
!Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the engine cooling system is not
sufficiently protected from corrosion and
overheating.
iHave the coolant regularly replaced at a
qualified specialist workshop and the
replacement confirmed in the Maintenance
Booklet.
Comply with the important safety precautions
for service products when handling coolant
(
Ypage 603).
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the
following tasks:
Rcorrosion protection
Rantifreeze protection
Rraising the boiling point
If the coolant has antifreeze protection down
to -35 ‡
( -37 †),the boiling point of the cool-
606Service products and filling capacities
Technical data