2012 MERCEDES-BENZ SL-CLASS ROADSTER brakes

segment illuminates and a constant
acoustic warning lasting a maximum of
2 seconds will sound for the second red
distance segment. The signal is canceled
when the automatic transmission is shifted
into park position P or the parking brake is
engaged.
RRear area: An intermittent acoustic
warning will sound when the first distance
segment illuminates. This signal quickens
with each additional distance segment lit.
When the eighth distance segment
illuminates, the acoustic warning becomes
a constant signal. The signal is canceled
when the automatic transmission is shifted
into drive position D, or park position P, or
the parking brake is engaged.
Switching the Parktronic system on/
off
The Parktronic system switches on
automatically when the ignition is switched
on.
XSwitching off: Press Parktronic
switch :.
Indicator lamp ; comes on.
XSwitching on: Press Parktronic switch :
again.
Parktronic system malfunction
There is a malfunction in the Parktronic
system, if only the red distance segments
illuminate and an acoustic warning sounds.
The Parktronic system will switch off
automatically after 20 seconds and indicator
lamp ; in Parktronic switch : comes on.
XHave the Parktronic system checked at an
authorized Mercedes-Benz Center as soon
as possible.
If only the red distance segments illuminate
and no acoustic warning sounds, the
Parktronic system sensors are dirty (e.g. dirt,
ice, snow and slush). Another cause could be
interference from other radio or ultrasonic
signals (e.g. truck air brakes, car wash, or
jackhammers). The Parktronic system will
switch off automatically after 20 seconds and
indicator lamp ; in Parktronic switch :
comes on.
XSwitch off the ignition.XClean the Parktronic system sensors
(Y page 218).
XSwitch on the ignition.
or
XCheck the Parktronic system operation at
another location to rule out interference
from outside radio or ultrasonic signals.
Driving systems147Controls in detail230_AKB; 6; 22, en-USd2ureepe,Version: 2.11.8.12009-07-28T18:49:58+02:00 - Seite 147Z

The brake fluid level is correct when it is
between lower mark (MIN) ; and upper
mark (MAX) : of the brake fluid reservoir.
Tires and wheels
Safety notes
Contact an authorized Mercedes-Benz Center
for information on tested and recommended
rims and tires for summer and winter
operation. They can also offer advice
concerning tire service and purchase.
GWarning!
Replace rims or tires with the same
designation, manufacturer and type as shown
on the original part. For further information
contact an authorized Mercedes-Benz Center.
If incorrectly sized rims and tires are
mounted, the wheel brakes or suspension
components can be damaged. Also, the
operating clearance of the wheels and the
tires may no longer be correct.
GWarning!
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, or if
the tires have sustained damage, replace
them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can result
in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or
recommended by Mercedes-Benz, since
previous damage cannot always be
recognized on retreads. The operating safety
of the vehicle cannot be assured when such
tires are used.
GWarning!
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possible
damage to your vehicle has occurred, you
should turn on the hazard warning flashers,
carefully slow down, and drive with caution to
an area which is a safe distance from the road.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle or tires
appear unsafe, have the vehicle towed to the
nearest authorized Mercedes-Benz Center or
tire dealer for repairs.GWarning!
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
could lose control of the vehicle. Continued
driving with a flat tire or driving at high speed
with a flat tire will cause excessive heat build-
up and possibly a fire.
Important guidelines
R Only use sets of tires and rims of the same
type and make.
R Tires must be of the correct size for the rim.
R Break in new tires for approximately
60 miles (100 km) at moderate speeds.
R Regularly check the tires and rims for
damage. Dented or bent rims can cause tire
inflation pressure loss and damage to the
tire beads.
R If the vehicle is heavily loaded, check tire
inflation pressure and correct as required.
R Do not allow your tires to wear down too
far. Adhesion properties on wet roads are
sharply reduced at tread depths of less
than 1
/ 8 in (3 mm).
R When replacing individual tires, you should
mount new tires on the front wheels first
(on vehicles with same-sized wheels all
around).
186Tires and wheelsOperation
230_AKB; 6; 22, en-USd2ureepe,Version: 2.11.8.12009-07-28T18:49:58+02:00 - Seite 186

Tire and Loading Information placard on the
driver’s door B-pillar ( Y page 194). If
necessary, add air to achieve the
recommended tire inflation pressure.XIf you have overfilled the tire, release tire
inflation pressure by pushing the metal
stem of the valve with e.g. a tip of a pen.
Then recheck the tire inflation pressure
with the tire gauge.XInstall the valve cap.XRepeat this procedure for each tire.
Advanced Tire Pressure Monitoring
System (Advanced TPMS)
Your vehicle is equipped with the Advanced
Tire Pressure Monitoring System (Advanced
TPMS). It measures the tire inflation pressure
in the vehicle’s tires and issues warnings in
case of pressure loss in one or more of the
tires.
The TPMS is equipped with a combination low
tire pressure/TPMS malfunction telltale
(USA) or a low tire pressure telltale (Canada)
in the instrument cluster. Depending on how
the telltale illuminates, it indicates a low tire
pressure condition or a malfunction in the
TPMS system itself:
R If the telltale illuminates continuously, one
or more of your tires is significantly
underinflated. There is no malfunction in
the TPMS.
R USA only: If the telltale flashes for 60
seconds and then stays illuminated, the
TPMS system itself is not operating
properly.
The TPMS only functions on wheels that are
equipped with the proper electronic sensors.
GWarning!
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to the
Tire and Loading Information placard or the
supplemental tire inflation pressure
information on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g. tire
blowout caused by a foreign object). In this
case bring the vehicle to a halt by carefully
applying the brakes and avoiding abrupt
steering maneuvers.GWarning!
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the Tire and Loading
Information placard on the driver’s door B-
pillar or the tire inflation 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 inflation pressure label, you should
determine the proper tire inflation 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 when
190Tires and wheelsOperation
230_AKB; 6; 22, en-USd2ureepe,Version: 2.11.8.12009-07-28T18:49:58+02:00 - Seite 190

Tire type code
Tire type code ? may, at the option of the
manufacturer, be used as a descriptive code
for identifying significant characteristics of
the tire.
Date of manufacture
The date of manufacture A identifies the
week and year of manufacture.
The first two figures identify the week,
starting with “01” to represent the first full
week of the calendar year. The second two
figures represent the year.
For example, “3208” represents the 32nd
week of 2008.
Tire ply material
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
This marking tells you about the type of cord
and number of plies in the sidewall : and
under the tread ;.
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power seats,
radio, and heater, to the extent that these
items are available as factory-installed
equipment (whether installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire. Air
pressure is expressed in pounds per square
inch (psi), kilopascal (kPa), or bar.
Aspect ratio
Dimensional relationship between tire
section height and section width expressed
in percentage.
Bar
Metric unit for air pressure. There are
14.5038 pounds per square inch (psi) to
1 bar; there are 100 kilopascals (kPa) to 1 bar.
Bead
The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle has
been sitting for at least 3 hours or driven no
more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with standard
equipment including the maximum capacity
of fuel, oil, and coolant, and, if so equipped,
air conditioning and additional optional
equipment, but without passengers and
cargo.
DOT (Department of Transportation)
A tire branding symbol which denotes the tire
meets requirements of the U.S. Department
of Transportation.
Tires and wheels205Operation230_AKB; 6; 22, en-USd2ureepe,Version: 2.11.8.12009-07-28T18:49:58+02:00 - Seite 205Z

GAWR (Gross Axle Weight Rating)
The GAWR is the maximum permissible axle
weight. The gross vehicle weight on each axle
must never exceed the GAWR for the front
and rear axle indicated on the certification
label located on the driver’s door B-pillar.
GVW (Gross Vehicle Weight)
The GVW comprises the weight of the vehicle
including fuel, tools, spare wheel, installed
accessories, passengers and cargo and, if
applicable, trailer tongue load. The GVW must
never exceed the GVWR indicated on the
certification label located on the driver’s door
B-pillar.
GVWR (Gross Vehicle Weight Rating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passengers,
fuel, and cargo and, if applicable, trailer
tongue load). It is indicated on the
certification label located on the driver’s door
B-pillar.
Kilopascal (kPa)
Metric unit for air pressure. There are 6.9 kPa
to 1 psi; another metric unit for air pressure
is bar. There are 100 kilopascals (kPa) to
1 bar.
Load index
Numerical code associated with the
maximum load a tire can support.
Maximum load rating
The maximum load in kilograms and pounds
that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
total load limit, and production options
weight.
Maximum permissible tire inflation
pressure
This number is the greatest amount of air
pressure that should ever be put in the tire.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by 68 kilograms
(150 lb).
Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
PSI (Pounds per square inch)
A standard unit of measure for air pressure.
Recommended tire inflation pressure
The recommended tire inflation pressure for
normal driving conditions is listed on the Tire
and Loading Information placard located on
the driver’s door B-pillar. It provides best
handling, tread life and riding comfort.
Supplemental information pertaining to
special driving situations can be found on the
tire inflation pressure label on the inside of
the fuel filler flap.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
206Tires and wheelsOperation
230_AKB; 6; 22, en-USd2ureepe,Version: 2.11.8.12009-07-28T18:49:58+02:00 - Seite 206

carpets in the footwell, make sure that the
pedals still have sufficient clearance.
During sudden driving or braking maneuvers,
the objects could get caught between the
pedals. You could then no longer brake or
accelerate. This could lead to accidents and
injury.
Power assistance
GWarning!
There is no power assistance for the steering
and the brake when the engine is not running.
Steering and braking requires significantly
more effort and you could lose control of the
vehicle and cause an accident as a result.
Do not turn off the engine while the vehicle is
in motion.
GWarning!
The brake system requires electrical energy
for operation.
A malfunction in the vehicle’s power supply or
electrical system may impair brake system
operation and switch it into its emergency
operation mode. In such a case, the red brake
warning lamp and warning messages in the
instrument cluster come on while driving. To
brake, the driver must then apply significantly
greater brake pedal pressure and depress the
pedal much further to obtain the expected
brake effect. If necessary, apply full pressure
to the brake pedal. Brakes are only applied to
the front wheels. Stopping distance is
increased! If there is a malfunction in the
electro-hydraulic brake system, we
recommend that the vehicle be transported
with all wheels off the ground using flatbed or
appropriate wheel lift/dolly equipment.
Brakes
Downhill grades
! When driving down long and steep
grades, relieve the load on the brakes by
shifting into a lower gear to use the
engine’s braking power. This helps prevent
overheating of the brakes and reduces
wear.
When using the engine’s braking power, a
drive wheel may not spin for an extended
period of time, e.g. on slippery road
surfaces. This may cause serious damage
to the drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
Continuous or hard braking
GWarning!
Resting your foot on the brake pedal will
cause excessive and premature wear of the
brake pads.
It can also result in the brakes overheating,
thereby significantly reducing their
effectiveness. It may not be possible to stop
the vehicle in sufficient time to avoid an
accident.
After hard braking, it is advisable to drive on
for some time, rather than immediately park,
so that the air stream will cool down the
brakes faster.
Wet roads
GWarning!
After driving in heavy rain for some time
without applying the brakes or through water
deep enough to wet brake components, the
first braking action may be somewhat
reduced and increased pedal pressure may be
necessary to obtain expected brake effect.
Maintain a safe distance from vehicles in
front.
To help prevent brake disk corrosion after
driving on wet or salt-covered roads, it is
advisable to brake the vehicle with
210Driving instructionsOperation
230_AKB; 6; 22, en-USd2ureepe,Version: 2.11.8.12009-07-28T18:49:58+02:00 - Seite 210

considerable force prior to parking. The heat
generated serves to dry the brakes.
Salt-covered roadsGWarning!
A layer of salt on the brake discs and the brake
linings may cause a delay in the braking
effect, resulting in a significantly increased
braking distance, which could lead to an
accident.
To avoid this danger, you should:
R occasionally brake carefully when you are
driving on salt-covered roads, so that any
layer of salt that may have built up on the
brake discs and the brake linings is
removed without putting other road users
at risk
R maintain a greater distance to the vehicle
ahead and drive with particular care
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are removed
from the brake disc
Brake service
! The brake fluid level in the reservoir may
be too low or the electro-hydraulic brake
system may be malfunctioning if the brake
warning lamp in the instrument cluster
comes on and an acoustic warning sounds
although the parking brake is released.
Observe additional messages in the
multifunction display that may appear.
Brake pad wear or a leak in the system may
be the reason for low brake fluid in the
reservoir.
Have the brake system inspected
immediately. Contact an authorized
Mercedes-Benz Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Center.
Only install brake pads and use brake fluid
recommended by Mercedes-Benz.GWarning!
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that safe
braking is substantially impaired. This could
result in an accident.
! Because the ESP ®
operates
automatically, the engine and ignition must
be shut off (SmartKey in starter switch
position 0 or 1 or KEYLESS-GO start/stop
button in position 0 or 1) when the parking
brake is being tested on a brake test
dynamometer or when the vehicle is being
towed with the front axle raised.
Active braking action through the ESP ®
may otherwise seriously damage the brake
system which is not covered by the
Mercedes-Benz Limited Warranty.
If your brake system is only subjected to
moderate loads, you should occasionally test
the effectiveness of the brakes by applying
above-normal braking pressure at higher
speeds. This will also enhance the grip of the
brake pads.
GWarning!
Make sure not to endanger any other road
users when carrying out these braking
maneuvers.
Refer to the description of the Brake Assist
System (BAS) ( Y page 56).
High-performance brake system
The high-performance brake system is only
available on SL 63 AMG and SL 65 AMG.
GWarning!
New vehicle brake pads and disks, and
replacement brake pads and disks may take
several hundred miles of driving until they
Driving instructions211Operation230_AKB; 6; 22, en-USd2ureepe,Version: 2.11.8.12009-07-28T18:49:58+02:00 - Seite 211Z

provide optimum braking efficiency. Until that
time, you may need to use increased brake
pedal pressure while braking. Please be aware
of this and adjust your driving and braking
accordingly during this break-in period.
Excessive high-demand braking will cause
correspondingly high brake wear. Please be
attentive to the brake warning lamp in the
instrument cluster and brake condition
messages in the multifunction display.
Especially for high-performance driving, it is
important to maintain and have the brake
system checked regularly.
The high-performance brake system is
designed to operate under the extremely high
operating demands required to
accommodate the performance capabilities
of the vehicle.
The brakes may produce a squeaking-type
noise depending on the
R vehicle speed
R brake force applied
R ambient conditions, e.g. temperature and
humidity
As with any brake system, the wear of
individual brake system components such as
brake pads or disks strongly depends on your
driving style and the conditions under which
you operate the vehicle. Thus, a driving style
calling for high-demand braking will cause
your vehicle’s brakes to wear more quickly.
Driving off
Warm up the engine smoothly. Do not place
full load on the engine until the operating
temperature has been reached.
! When driving off on a slippery surface, do
not allow a drive wheel to spin for an
extended period with the ESP ®
switched
off. Doing so may cause serious damage to
the drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
! Simultaneously depressing the
accelerator pedal and applying the brakes
reduces engine performance and causes
premature brake and drivetrain wear which
is not covered by the Mercedes-Benz
Limited Warranty.
Hydroplaning
Depending on the depth of the water layer on
the road, hydroplaning may occur, even at low
speeds and with new tires. In heavy rain or
when conditions indicate possible
hydroplaning:
XReduce vehicle speed.XAvoid track grooves in the road.XApply brakes cautiously.
Standing water
! Do not drive through flooded areas.
Before driving through water, determine its
depth.
If you must drive through standing water,
drive slowly to prevent water from entering
the passenger compartment or the engine
compartment. Water in these areas could
cause damage to electrical components or
wiring of the engine or transmission, or
could result in water being ingested by the
engine through the air intake causing
severe internal engine damage. Any such
damage is not covered by the Mercedes-
Benz Limited Warranty.
Driving abroad
If you plan to drive the vehicle outside the U.S.
or Canada, you should request dealer
network information for your destination from
any authorized Mercedes-Benz Center.
212Driving instructionsOperation
230_AKB; 6; 22, en-USd2ureepe,Version: 2.11.8.12009-07-28T18:49:58+02:00 - Seite 212