2011 MERCEDES-BENZ S-Class fuel pressure

EngineProblemPossible causes/consequences and M Solutions;
The yellow Check
Engine warning lamp
lights up while the
engine is running.There may be a malfunction, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R the fuel system
The emission limit values may have been exceeded and the engine
may be breaking in emergency mode.XHave the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states/provinces, you are required by law to visit a
qualified specialist workshop as soon as the Check Engine
warning lamp lights up. If necessary, check whether this is the
case in the state/province you are in.
The yellow reserve fuel
warning lamp flashes
while the engine is
running.The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.XCheck that the fuel filler cap is correctly closed.XIf the fuel filler cap is not correctly closed: close the fuel filler
cap.XIf the fuel filler cap is closed: visit a qualified specialist
workshop.The yellow reserve fuel
warning lamp lights up
while the engine is
running.The amount of fuel in the tank has dropped into the reserve range.XRefuel at the nearest gas station.418Warning and indicator lamps in the instrument clusterOn-board computer and displays

inside of the fuel filler flap of your vehicle, if there is one). If your vehicle has tires which are a
different size to those on the tire and load data label or those specified in the tire pressure table,
if there is one, you should determine the correct tire pressure for these tires.
As an added safety feature, your vehicle has been equipped with a tire pressure monitor (TPMS).
An indicator lamp lights up if one or more of your tires are significantly underinflated. Accordingly,
when the low tire pressure indicator lamp lights up, 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.
An excessively low tire pressure also increases fuel consumption, reduces the service life of the
tires and may impair the driving and braking characteristics of the vehicle. 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 at which the low tire
pressure indicator lamp of the TPMS lights up.
USA only:
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 combined with the low tire
pressure indicator lamp. When the system detects a malfunction, the indicator lamp will flash
for approximately one minute and then remain illuminated. This sequence will continue upon
subsequent vehicle start-ups as long as the malfunction exists. When the malfunction indicator
is lit, 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 indicator 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.420Warning and indicator lamps in the instrument clusterOn-board computer and displays

"Technical Data" section to avoid damage
to the vehicle or the wheels.
R Only use snow chains when driving on an
area completely covered by snow. Do not
exceed the maximum permissible speed of
30 mph (50 km/h). Remove the snow
chains as soon as possible when you are no
longer driving on snow-covered roads.
R Local regulations may restrict the use of
snow chains. Applicable regulations must
be observed if you wish to mount snow
chains.
R Snow chains must not be mounted on
emergency spare wheels.
If you intend to mount snow chains, please
bear the following points in mind:
R you may not attach snow chains to all
wheel-tire combinations; see the "Tires and
wheels" section in the "Technical data"
chapter.
R mount snow chains only in pairs and only
on the rear wheels. Observe the
manufacturer's installation instructions.
! If snow chains are mounted on the front
wheels, the snow chains could grind
against the bodywork or components of the
chassis. This could result in damage to the
vehicle or the tires.
! Vehicles with steel wheels
If you wish to mount snow chains to steel
wheels, make sure that you remove the
respective wheels' hubcaps first. The
hubcaps may otherwise be damaged.
i You may wish to deactivate
ESP ®
(Y page 69) when pulling away with
snow chains installed. This way you can
allow the wheels to spin in a controlled
manner, achieving an increased driving
force (cutting action).Tire pressure
Tire pressure specifications
GWarning
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.
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.
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver's door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
You will find a table of recommended tire
pressures on the Tire and Loading
Information placard on the B-pillar on the
driver's side ( Y page 490). You will find a
table of tire pressures for various operating
conditions on the inside of your vehicle's fuel
filler flap.
Use a suitable pressure gauge. The outer
appearance of a tire does not permit any
reliable conclusion about the tire pressure.
On vehicles equipped with the electronic tire
pressure monitor, the tire pressure can be
checked using the on-board computer.
GWarning
Should the tire pressure drop repeatedly:
Tire pressure483Tires and wheelsZ

Rcheck the tire for foreign bodies.
R check whether the wheel is losing air or the
valve is leaking.
R make sure that only a valve cap approved
by Mercedes-Benz is installed on the tire
valve.
Tire pressures that are too low have a
negative effect on vehicle safety, which could
lead you to cause an accident.
Only correct tire pressures when the tires are
cold. The tires are cold when the vehicle has
been parked for at least three hours or driven
for less than 1 mile (1.6 km). The tire
temperature changes depending on the
outside temperature, the vehicle speed and
the tire load. If the tire temperature changes
by 18 ‡ (10 †), the tire pressure changes by
approximately 10 kPa (0.1 bar/1.5 psi). Take
this into account when checking the pressure
of warm tires and only correct the tire
pressure if it is too low for the current
operating conditions. If you check the tire
pressure when the tires are warm, the reading
will be higher than if the tires were cold. This
is normal. Do not reduce the tire pressure to
the value specified for cold tires. The tire
pressure would otherwise be too low.
Observe the recommended tire pressure
specifications for cold tires on the Tire and
Loading Information placard on the B-pillar on
the driver's side.
i The specifications given on the following
Tire and Loading Information placard are
examples. Tire pressure specifications are
vehicle-specific and may deviate from the
data shown here. The tire pressure
specifications for your vehicle can be found
on the Tire and Loading Information placard
of your vehicle.
You will find recommended tire pressure
specifications : for cold tires and for a fully
loaded vehicle on the Tire and Loading
Information placard. The tire pressure
specifications apply to tires which are
installed at the factory.
Important notes on tire pressure
GWarning
If the tire pressure drops repeatedly, check
the tires for punctures from foreign objects
and/or whether air is leaking from the valves
or from around the rim.
The temperature and pressure of the tires
increase when the vehicle is in motion. This
is dependent on the driving speed and the
load.
If you wish to drive at high speeds of
100 mph (160 km/h) or higher when this is
allowed, use the tire pressure table on the
inside of the fuel filler flap to set the correct
tire pressures when the wheels are cold. If the
tire pressure is not set correctly, this can lead
to an excessive build up of heat and a sudden
loss of pressure.
For more information, contact a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
i Ride comfort may be affected if the tire
pressure is adjusted to the recommended
value for speeds of over
100 mph(160 km/h).
484Tire pressureTires and wheels

Make sure that the tire pressure for normal
speeds is adopted again.
Additional specifications of tire pressure
values for loads can also be found on the tire
pressure table on the inside of the fuel filler
flap.
The tire pressure for emergency spare wheels
can be found:
R on the yellow label on the wheel rim of the
emergency spare wheel
R in the "Wheel and tire combinations"
section ( Y page 503) of this Operator's
Manual
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
i The specifications shown in the examples
in the tire pressure tables are only
examples. Tire pressure specifications are
vehicle-specific and may deviate from the
data shown here. The tire pressure
specifications that are valid for your vehicle
can be found on your vehicle's tire pressure
table.
The tire pressures in the tire pressure table
on the inside of the fuel filler flap are valid for
all approved tires installed at the factory,
unless stated otherwise.
Tire pressure table for all approved tires installed
at the factory (example)
If the tire pressure precedes a tire size, the
tire pressure specification is only valid for this
tire size. The vehicle loading conditions
"partially laden" or "fully laden" are specified
using a differing number of persons and
luggage in the table. The actual number of
seats may differ from this.
Tire pressure table with tire sizes (example)
Some tire pressure tables only show the rim
diameter instead of the complete tire size,
e.g. R18 . The rim diameter is a component of
the tire size and can be read from the tire
sidewall ( Y page 496).
Tire pressure too low or too high
Underinflated tires
GWarning
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.
Underinflated tires can:
R wear excessively and/or unevenly
R adversely affect fuel economy
Tire pressure485Tires and wheelsZ

Rfail from being overheated
R adversely affect handling
Overinflated tiresGWarning
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.
Overinflated tires can:
R adversely affect handling
R wear excessively and/or unevenly
R be more likely to become damaged
R adversely affect ride comfort
R increase stopping distance
Maximum tire pressure
GWarning
Never exceed the maximum 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 overheated.
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.
:Maximum permitted tire pressure
(example)
i The actual values for tires are specific to
each vehicle and may deviate from the
values in the illustration.
When adjusting the tire pressures always
observe the recommended tire pressure for
your vehicle ( Y page 483).
Checking tire pressures
Important safety notes
GWarning
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.
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.
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver's door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
486Tire pressureTires and wheels

Check the tire pressure at least once a month.
Only check and correct tire pressures when
the tires are cold ( Y page 483).
Checking the tire pressures manually
In order to determine and adjust the tire
pressures, proceed as follows:
XRemove the valve cap of the tire you wish
to check.XPress the tire pressure gauge securely onto
the valve.XRead the tire pressure and compare it with
the recommended value on the Tire and
Loading Information placard on the
B-pillar on the driver's side of your vehicle.XIf necessary, increase the tire pressure to
the recommended value ( Y page 483).XIf the tire pressure is too high, release air
by pressing down the metal pin in the valve
using the tip of a pen, for example. Then,
check the tire pressure again using the tire
pressure gauge.XScrew the valve cap onto the valve.XRepeat the steps for the other tires.
Tire pressure monitor
Important safety notes
If a tire pressure monitor is installed, the
vehicle's wheels have sensors installed that
monitor the tire pressures in all four tires. The
tire pressure monitor warns you when the
pressure drops in one or more of the tires. The
tire pressure monitor only functions if the
correct wheel electronics units are installed
in all wheels.
The tire pressure monitor has a yellow
warning lamp in the instrument cluster for
indicating pressure loss/malfunctions (USA)
or pressure loss (Canada). Depending on how
the warning lamp flashes or lights up, a tire
pressure that is too low or a malfunction in
the tire pressure monitor is displayed:
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 USA only: if the warning lamp flashes for
60 seconds and then remains lit constantly,
the tire pressure monitor is malfunctioning.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
Tire pressure487Tires and wheelsZ

XPress the 9 or : button to select
Tire Pressure .XPress the a button.
The current tire pressure for each wheel will
be displayed in the multifunction display.
If the vehicle has been parked for longer than
20 minutes, the Tire Pressures
Displayed After Driving A Few
Minutes message appears in the display.
After a teach-in period, the tire pressure
monitor automatically recognizes new wheels
or new sensors. As long as a clear allocation
of the tire pressure values to the individual
wheels is not possible, the Tire Pressure
Monitor Active message is shown instead
of the tire pressure display. The tire pressures
are already being monitored.
i If a spare wheel/emergency spare wheel
is mounted, the system may continue to
show the tire pressure of the wheel that has
been removed for a few minutes. If this
occurs, note that the value displayed for
the position where the spare wheel is
mounted is not the same as the spare
wheel/emergency spare wheel's current
tire pressure.
TPMS warning messages
If the tire pressure monitor detects a
significant pressure loss on one or more tires,
a warning message is shown in the
multifunction display. A warning tone also
sounds and the tire pressure warning lamp
lights up in the instrument cluster.
For each tire that is affected by a significant
loss of pressure, the tire pressure is shown in
yellow.
If the Correct Tire Pressure message
appears in the multifunction display:
XCheck the tire pressure on all four wheels
and correct it if necessary.
i If the wheel positions on the vehicle are
interchanged, 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 monitorGWarning
It is the driver's responsibility to set the tire
inflation pressure to the recommended cold
tire inflation pressure. Underinflated tires
affect the ability to steer or brake the vehicle.
You might lose control over the vehicle.
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.
The TPMS must be restarted when you set the
tire pressure to a new value (as a result of
changed handling or load characteristics, for
example). The TPMS then monitors the new
tire pressure values.
i Canada only: in most cases, the tire
pressure monitor recognizes the new
reference values automatically. However,
you can also define reference values
manually as described here.
Restart the tire pressure monitor after you
have set the tire pressure to the value
recommended for the desired driving
situation ( Y page 483). Only correct tire
pressures on cold tires. Comply with the
recommended tire pressures on the Tire and
Loading Information placard on the B-pillar on
the driver's side Additional tire pressure
values for driving at high speeds or with heavy
loads can be found in the Tire Pressure table
on the inside of the fuel filler flap.
XMake sure that the tire pressure is correct
on all four wheels.XMake sure that the SmartKey is in position
2 in the ignition lock.XPress the = or ; button to select the
Service menu.Tire pressure489Tires and wheelsZ