2008 MERCEDES-BENZ SLK55AMG fuel pressure

320 Operation
Tires and wheels
Press reset buttonJ (page 118).
The following message will appear in
the multifunction display:
Restart tire
pressure monitor?
Press button æ.
The following message will appear in
the multifunction display:
Tire Pressure Monitor
Restarted
After driving a few minutes the current
tire inflation pressure values are
accepted as reference pressures and
then monitored.
If you wish to cancel activation:
Press button ç.Potential problems associated with
underinflated and overinflated tires
Underinflated tires
Underinflated tires can:

cause excessive and uneven tire wear

adversely affect fuel economy

lead to tire failure from being
overheated

adversely affect handling
characteristicsOverinflated tires
Overinflated tires can:

adversely affect handling
characteristics

cause uneven tire wear

be more prone to damage from road
hazards

adversely affect ride comfort

increase stopping distance
Warning!G
Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being
overheated.
Warning!G
Follow recommended tire inflation
pressures.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.


328 Operation
Tires and wheels
Maximum tire inflation pressure
1Maximum permissible tire inflation
pressure
This is the maximum permissible tire
inflation pressure for the tire.Always follow the recommended tire
inflation pressure (
page 311) for proper
tire inflation. Uniform Tire Quality Grading Standards (U.S. vehicles)
Tire manufacturers are required to grade
tires based on three performance
factors: treadwear, traction and
temperature resistance.
1Treadwear
2Traction
3Temperature resistance
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
Warning!G
Never exceed the max. tire inflation
pressure. Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being over-
heated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.

331 Operation
Tires and wheels
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), or kilopascal (kPa), or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another 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 three hours or
driven no more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (Department of Transportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross 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 (G
ross 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 GWV must never exceed the
GWVR indicated on the certification label
located on the driver’s door B-pillar.

332 Operation
Tires and wheels
GVWR (Gross Vehicle Weight Rating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passen-
gers, fuel, and cargo and, if applicable,
trailer tongue load). It is indicated on
certification label located on the driver’s
door B-pillar.
Kilopascal (kPa)
The metric unit for air pressure. There are
6.9 kPa to 1 psi; another metric unit for air
pressure is bars. There are 100 kilopascals
(kPa) to 1 bar.
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 tire inflation pressure
This number is the greatest amount of air
pressure that should ever be put in the tire
under normal driving conditions.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by
68 kilograms (150 lbs).
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
-> bar, kilopascal (kPa).
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 and
provides best handling, tread life and
riding comfort. If so equipped, supplemen-
tal 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.
Sidewall
The portion of a tire between the tread and
the bead.

357 Practical hints
What to do if …
Warning!G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
Tire and Loading Information placard on the
driver’s door B-pillar (
page 307) or, if
available, the tire inflation pressure label on
the inside of the fuel filler flap (
page 291).
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 deter-
mine the proper tire inflation pressure for
those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires is significantly underinflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate them to
the proper pressure. Driving on a significant-
ly underinflated tire causes the tire to over-
heat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehi-
cle’s handling and stopping ability. Please
note that the TPMS is not a substitute for
proper tire maintenance, and it is the driv-
er’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.Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate
when the system is not operating properly.
The TPMS malfunction indicator is com-
bined with the low tire pressure telltale.
When the system detects a malfunction, the
telltale will flash for approximately 1 minute
and then remain continuously illuminated.
This sequence will continue upon subse-
quent vehicle start-ups as long as the mal-
function 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
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.

369 Practical hints
What to do if …
Display messagePossible cause/consequencePossible solution
Check tires,
then restart
Run Flat
Indicator.There was a warning message about
a loss in tire inflation pressure and
the Run Flat Indicator* has not been
restarted yet.Make sure that the correct tire inflation pressure is set for each tire.
Then restart the Run Flat Indicator* (page 316).
Run Flat Indicator
InoperativeThe Run Flat Indicator* is malfunc-
tioning.Have the Run Flat Indicator* checked by an authorized
Mercedes-Benz Center.
Tire Pressure
Check TiresThe Run Flat Indicator* indicates that
the pressure is too low in one or more
tires.Carefully bring the vehicle to a halt, avoiding abrupt steering and
braking maneuvers. Observe the traffic situation around you.
Check and adjust the tire inflation pressure as required (page 313).
If necessary, change the wheel (page 408).
Restart the Run Flat Indicator* after adjusting the tire inflation pres-
sure values (
page 313).
Warning!G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
may lose control of the vehicle. Continued
driving with a flat tire will cause excessive
heat build-up and possibly a fire.
Warning!G
Follow recommend tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being over-
heated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.

370 Practical hints
What to do if …
Display messagePossible cause/consequencePossible solution
Tire Pressure Monitor
InoperativeThe TPMS is malfunctioning.Have the TPMS checked by an authorized Mercedes-Benz
Center.
Tire Pressure Monitor
Inoperative
No Wheel SensorsThere are wheels without appropriate
wheel sensors mounted (e.g. winter tires).Have the TPMS checked by an authorized Mercedes-Benz
Center.
Have the wheel sensors installed by an authorized
Mercedes-Benz Center.
Tire Pressure Monitor
Currently UnavailableThe TPMS is unable to monitor the tire
pressure due to a nearby radio interfer-
ence source.As soon as the causes of the malfunction have been re-
moved, the TPMS automatically becomes active again after
a few minutes driving.
Warning!G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
may lose control of the vehicle. Continued
driving with a flat tire will cause excessive
heat build-up and possibly a fire.
Warning!G
Follow recommend tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being over-
heated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.

379 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
NEngine Oil Level
Reduce Oil LevelSLK 55 AMG only:
You have added too much engine
oil. There is a risk of damaging the
engine or the catalytic converter.Have oil siphoned or drained off.
Observe all legal requirements with respect
to its disposal.
Engine Oil Level
Stop, turn engine off.There is no oil in the engine. There
is a danger of engine damage.Stop the vehicle in a safe location or as soon
as it is safe to do so.
Turn off the engine.
Apply the parking brake (page 59).
Add engine oil (page 299) and check the
engine oil level (
page 296).
AReserve FuelThe fuel level has dropped below
the reserve mark.Refuel at the next gas station (page 291).
4Gas Cap
Is OpenA loss of pressure has been detect-
ed in the fuel system. The fuel cap
may not be closed properly or the
fuel system may be leaky.Check the fuel cap (page 291).
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an autho-
rized Mercedes-Benz Center.