2014 MERCEDES-BENZ SL-CLASS ROADSTER service

electronic components, such as the
alternator, may be damaged.
R you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic
system may be damaged.
R the transmission is locked in position P
after disconnecting the battery. The
vehicle is secured against rolling away.
You can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be installed securely
during operation.
In order for the battery to achieve the
maximum possible service life, it must always
be sufficiently charged.
Comply with safety precautions and take
protective measures when handling
batteries. Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the
battery. Avoid creating sparks. Battery acid is caustic. Avoid
contact with skin, eyes or clothing.
Wear suitable protective clothing,
especially gloves, apron and
faceguard.
Rinse any acid spills immediately
with clear water. Contact a
physician if necessary. Wear eye protection.
Keep children away.
Observe this Operator's Manual. The vehicle battery, like other batteries, can
discharge over time if you do not use the
vehicle. In this case, have the battery
disconnected at a qualified specialist
workshop. You can also charge the battery
with a charger recommended by Mercedes-
Benz. Contact a qualified specialist workshop
for further information.
Have the battery condition of charge checked
more frequently if you use the vehicle mainly
for short trips or if you leave it standing idle
for a lengthy period. Consult a qualified
specialist workshop if you wish to leave your
vehicle parked for a long period of time.
i Remove the SmartKey if you park the
vehicle and do not require any electrical
consumers. The vehicle will then use very
little energy, thus conserving battery
power.
i After an interruption to the power supply,
e.g. due to a discharged battery, you must
reset the clock. Information on setting the
clock can be found in the Digital Operator's
Manual. Charging the battery
G
WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a
risk of an explosion.
Particularly avoid fire, open flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with
water and seek medical attention. Battery (vehicle)
233Breakdown assistance Z

G
WARNING
A discharged battery can freeze at
temperatures below freezing point. When
jump-starting the vehicle or charging the
battery, gases can escape from the battery.
There is a risk of an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
! Only use battery chargers with a
maximum charging voltage of 14.8 V.
! Only charge the battery using the jump-
starting connection point.
The jump-starting connection point is in the
engine compartment.
If, at low temperatures, the indicator lamps/
warning lamps in the instrument cluster do
not light up, it is highly likely that the
discharged battery has frozen. In this case,
you may neither charge the battery nor jump-
start the vehicle. The service life of a thawed-
out battery may be shorter. The starting
characteristics can be impaired, particularly
at low temperatures. Have the thawed-out
battery checked at a qualified specialist
workshop.
Read the battery charger's operating
instructions before charging the battery.
X Open the hood.
X Connect the battery charger to the positive
terminal and ground point in the same
order as when connecting the donor
battery in the jump-starting procedure
(Y page 235). 234
Battery (vehicle)Breakdown assistance

Jump-starting
For the jump-starting procedure, use only the jump-starting connection point, consisting of a
positive terminal and a ground point, in the engine compartment. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing. Do not inhale any battery gases. Do not lean over
the battery. Keep children away from batteries. Wash battery acid immediately with water and
seek medical attention. G
WARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk
of an explosion.
Particularly avoid fire, open flames, creating sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting. Do not lean over a battery. G
WARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
R Never place metal objects or tools on a battery.
R It is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
R When jump-starting, make sure that the battery poles with identical polarity are connected.
R It is particularly important to observe the described order when connecting and disconnecting
the jumper cables.
R Never connect or disconnect the battery terminals while the engine is running. G
WARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting the
vehicle or charging the battery, gases can escape from the battery. There is a risk of an explosion.
Allow the frozen battery to thaw out before charging it or jump-starting.
! Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter could be
damaged by the non-combusted fuel.
If, at low temperatures, the indicator lamps/warning lamps in the instrument cluster do not
light up, it is highly likely that the discharged battery has frozen. In this case, you may neither
charge the battery nor jump-start the vehicle. The service life of a thawed-out battery may be
shorter. The starting characteristics can be impaired, particularly at low temperatures. Have
the thawed-out battery checked at a qualified specialist workshop. Jump-starting
235Breakdown assistance Z

other obstacles. If it is necessary to drive over
curbs, speed humps or similar elevations, try
to do so slowly and at an obtuse angle.
Otherwise, the tires, particularly the
sidewalls, may be damaged. Regular checking of wheels and tires
G
WARNING
Damaged tires can cause tire inflation
pressure loss. As a result, you could lose
control of your vehicle. There is a risk of
accident.
Check the tires regularly for signs of damage
and replace any damaged tires immediately.
Regularly check the wheels and tires of your
vehicle for damage at least once a month, as
well as after driving off-road or on rough
roads. Damaged wheels can cause a loss of
tire pressure. Pay particular attention to
damage such as:
R cuts in the tires
R punctures
R tears in the tires
R bulges on tires
R deformation or severe corrosion on wheels
Regularly check the tire tread depth and the
condition of the tread across the whole width
of the tire (Y page 245). If necessary, turn
the front wheels to full lock in order to inspect
the inner side of the tire surface.
All wheels must have a valve cap to protect
the valve against dirt and moisture. Do not
mount anything onto the valve other than the
standard valve cap or other valve caps
approved by Mercedes-Benz for your vehicle.
Do not use any other valve caps or systems,
e.g. tire pressure monitoring systems.
Regularly check the pressure of all the tires
particularly prior to long trips. Adjust the tire
pressure as necessary (Y page 246).The service life of tires depends on the
following factors amongst other things:
R
Driving style
R Tire pressure
R Distance covered Important safety notes on the tire
tread
G
WARNING
Insufficient tire tread will reduce tire traction.
The tire is no longer able to dissipate water.
This means that on wet road surfaces, the risk
of hydroplaning increases, in particular where
speed is not adapted to suit the driving
conditions. There is a risk of accident.
If the tire pressure is too high or too low, tires
may exhibit different levels of wear at
different locations on the tire tread. Thus, you
should regularly check the tread depth and
the condition of the tread across the entire
width of all tires.
Minimum tire tread depth for:
R Summer tires: âin (3 mm)
R M+S tires: ãin (4 mm)
For safety reasons, replace the tires before
the legally prescribed limit for the minimum
tire tread depth is reached. Bar indicator
:for tread wear is integrated
into the tire tread.
Treadwear indicators (TWI) are required by
law. Six indicators are positioned on the tire
tread. They are visible once the tread depth Operation
245Wheels and tires Z

Tire pressure monitor
General notes If a tire pressure monitor is installed, the
vehicle's wheels have sensors that monitor
the tire pressures in all four tires. The tire
pressure monitor warns you if the pressure
drops in one or more of the tires. The tire
pressure monitor only functions if the correct
sensors are installed on all wheels.
Information on tire pressures is displayed in
the multifunction display. After a few minutes
of driving, the current tire pressure of each
tire is shown in the Service
Service menu of the
multifunction display. Example: current tire pressure display
For information on the message display, refer
to the "Checking the tire pressure
electronically" section (Y page 251).
Important safety notes G
WARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure
recommended by the vehicle manufacturer
on the Tire and Loading Information placard
on the driver's door B-pillar or the tire
pressure label on the inside of the fuel filler
flap. If your vehicle has tires of a different size
than the size indicated on the Tire and Loading
Information placard or the tire pressure label,
you should determine the proper tire pressure
for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring
system (TPMS) that illuminates a low tire
pressure telltale when one or more of your tires are significantly underinflated.
Accordingly, when the low tire pressure
telltale illuminates, you should stop and check
your tires as soon as possible, and inflate
them to the proper pressure. Driving on a
significantly underinflated tire causes the tire
to overheat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle's
handling and stopping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the
driver's responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
USA only:
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate if the
system is not operating properly. The TPMS
malfunction indicator is combined with the
low tire pressure telltale. When the system
detects a malfunction, the warning lamp will
flash for approximately a minute and then
remain continuously illuminated. This
sequence will be repeated every time the
vehicle is started as long as the malfunction
exists.
When the malfunction indicator is illuminated,
the system may not be able to detect or signal
low tire pressure as intended. TPMS
malfunctions may occur for a variety of
reasons, including the installation of
incompatible replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on your
vehicle to ensure that the replacement or
alternate tires and wheels allow the TPMS to
continue to function properly.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
(Y page 246). Note that the correct tire
pressure for the current operating situation 250
Tire pressureWheels and tires

must first be taught-in to the tire pressure
monitor. If there is a substantial loss of
pressure, the warning threshold for the
warning message is aligned to the reference
values taught-in. Restart the tire pressure
monitor after adjusting the pressure of the
cold tires (Y page 252). The current
pressures are saved as new reference values.
As a result, a warning message will appear if
the tire pressure drops significantly.
The tire pressure monitor does not warn you
of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(Y page 246).
The tire pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tire is penetrated by a foreign object. In the
event of a sudden loss of pressure, bring the
vehicle to a halt by braking carefully. Avoid
abrupt steering maneuvers.
The tire pressure monitor has a yellow
warning lamp in the instrument cluster for
indicating a pressure loss or malfunction.
Whether the warning lamp flashes or lights up
indicates whether a tire pressure is too low or
the tire pressure monitor is malfunctioning:
R if the warning lamp is lit continuously, the
tire pressure on one or more tires is
significantly too low. The tire pressure
monitor is not malfunctioning.
R if the warning lamp flashes for around a
minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
i In addition to the warning lamp, a
message appears in the multifunction
display.
Further information can be found on
(Y page 174).
If the tire pressure monitor is malfunctioning,
it may take more than ten minutes for the tire
pressure warning lamp to inform you of the
malfunction by flashing for approximately one
minute and then remaining lit. When the
malfunction has been rectified, the tire
pressure warning lamp goes out after a few
minutes of driving. The tire pressure values indicated by the on-
board computer may differ from those
measured at a gas station with a pressure
gauge. The tire pressures shown by the on-
board computer refer to those measured at
sea level. At high altitudes, the tire pressure
values indicated by a pressure gauge are
higher than those shown by the on-board
computer. In this case, do not reduce the tire
pressures.
The operation of the tire pressure monitor can
be affected by interference from radio
transmitting equipment (e.g. radio
headphones, two-way radios) that may be
being operated in or near the vehicle.
Checking the tire pressure
electronically X
Make sure that the SmartKey is in position
2in the ignition lock (Y page 121).
X Press the =or; button on the
steering wheel to select the Service
Service
menu.
X Press the 9or: button to select
Tire Pressure Tire Pressure .
X Press the abutton.
The current tire pressure of each tire is
shown in the multifunction display.
If the vehicle has been parked for over
20 minutes, the Tire pressure will be Tire pressure will be
displayed after driving a few
displayed after driving a few
minutes minutes message appears.
After a teach-in process, the tire pressure
monitor automatically detects new wheels or
new sensors. As long as a clear allocation of
the tire pressure value to the individual
wheels is not possible, the Tire Pressure Tire Pressure
Monitor Active
Monitor Active display message is shown
instead of the tire pressure display. The tire
pressures are already being monitored. Tire pressure
251Wheels and tires Z

Tire pressure monitor warning
messages
If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message
is shown in the multifunction display and the
yellow tire pressure monitor warning lamp
comes on.
R If the Please Correct Tire Pressure
Please Correct Tire Pressure
message appears in the multifunction
display, the tire pressure in at least one tire
is too low and must be corrected at the next
opportunity.
R If the Check
Check Tires Tiresmessage appears in the
multifunction display, the tire pressure in
one or more tires has dropped significantly
and the tires must be checked.
R If the Warning Tire Malfunction
Warning Tire Malfunction
appears in the multifunction display, the
tire pressure in one or more tires has
dropped suddenly and the tires must be
checked.
Observe the instructions and safety notes in
the display messages in the "Tires" section
(Y page 174).
i If the wheel positions on the vehicle are
rotated, the tire pressures may be
displayed for the wrong positions for a
short time. This is rectified after a few
minutes of driving, and the tire pressures
are displayed for the correct positions.
Restarting the tire pressure monitor When you restart the tire pressure monitor,
all existing warning messages are deleted and
the warning lamps go out. The monitor uses
the currently set tire pressures as the
reference values for monitoring. In most
cases, the tire pressure monitor will
automatically detect the new reference
values after you have changed the tire
pressure. However, you can also define
reference values manually as described here.
The tire pressure monitor then monitors the
new tire pressure values. X
Set the tire pressure to the value
recommended for the corresponding
driving situation on the Tire and Loading
Information placard on the driver's side
B-pillar (Y page 246).
Additional tire pressure values for different
loads can also be found on the tire pressure
table on the inside of the fuel filler flap
(Y page 246).
X Make sure that the tire pressure is correct
on all four wheels.
X Make sure that the SmartKey is in position
2in the ignition lock.
X Press the =or; button on the
steering wheel to select the Service
Service
menu.
X Press the 9or: button to select
Tire Pressure Tire Pressure .
X Press the abutton.
The multifunction display shows the
current tire pressure for the individual tires
or the Tire pressure will be
Tire pressure will be
displayed after driving a few displayed after driving a few
minutes minutes message.
X Press the :button.
The Use Current Pressures as New
Use Current Pressures as New
Reference Values
Reference Values message appears in
the multifunction display.
If you wish to confirm the restart:
X Press the abutton.
The Tire Pressure Monitor Tire Pressure Monitor
Restarted
Restarted message appears in the
multifunction display.
After driving for a few minutes, the system
checks whether the current tire pressures
are within the specified range. The new tire
pressures are then accepted as reference
values and monitored.
If you wish to cancel the restart:
X Press the %button.
The tire pressure values stored at the last
restart will continue to be monitored. 252
Tire pressureWheels and tires

Example:
R
Treadwear grade: 200
R Traction grade: AA
R Temperature grade: A
All passenger car tires must conform to the
statutory safety requirements in addition to
these grades.
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
Treadwear The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified
U.S. government course. For example, a tire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm, due to variations in driving habits,
service practices and differences in road
characteristics and climate conditions.
Traction G
WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
! Avoid wheelspin. This can lead to damage
to the drive train.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
the tire's ability to stop on a wet surface as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance. The safe speed on a wet, snow covered or icy
road is always lower than on dry road
surfaces.
You should pay special attention to road
conditions when temperatures are around
freezing point.
Mercedes-Benz recommends a minimum
tread depth of
ãin(4 mm) on all four winter
tires. Observe the legally required minimum
tire tread depth (Y page 245). Winter tires can
reduce the braking distance on snow-covered
surfaces in comparison with summer tires.
The braking distance is still much further than
on surfaces that are not icy or covered with
snow. Take appropriate care when driving.
Further information on winter tires (M+S
tires) can be found in the Digital Operator's
Manual.
Temperature G
WARNING
The temperature grade for this tire is
established for a tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, or excessive loading, either
separately or in combination, can cause
excessive heat build-up and possible tire
failure.
The temperature grades are A (the highest),
B, and C. These represent the tire's
resistance to the generation of heat and its
ability to dissipate heat when tested under
controlled conditions on a specified indoor
laboratory test wheel. Sustained high
temperature can cause the material of the tire
to degenerate and reduce tire life, and
excessive temperature can lead to sudden
tire failure. The grade C corresponds to a level
of performance which all passenger car tires
must meet under the Federal Motor Vehicle
Safety Standard No. 109. Grades B and A
represent higher levels of performance on the
laboratory test wheel than the minimum
required by law. 256
All about wheels and tiresWheels and tires