2008 BMW 135I COUPE tire pressure

Technology for driving comfort and safety
80
Technology for driving comfort and safety
Park Distance Control PDC*
The concept
The PDC assists you with maneuvering in tight
parking spaces. Acoustic signals and a visual
indicator
warn you of the presence of an object
behind your vehicle. Four ultrasonic sensors in
the bumper measure the distance.
These sensors have a range of approx. 6.5 ft/
2 m. However, an acoustic warning does not
sound until an object is approx. 24 in/60 cm
from the corner sensors, or approx. 5 ft/1.50 m
from the center sensors.
PDC is a parking aid that can indicate
objects when they are approached
slowly, as is usually the case when parking.
Avoid approaching an object at high speed, oth-
erwise physical circumstances may lead to the
system warning being issued too late.<
Switching on automatically
With the engine running or the ignition switched
on, the system is activated after approx. 1 sec-
ond when you engage reverse gear or move the
automatic transmission selector lever to
position R. Wait this short period before driving.
Switching off automatically
After approx. 55 yd/50 m of driving or above
approx. 20 mph/30 km/h, the system switches
off and the LED goes out.
Signal tones
When nearing an object, its position is indicated
correspondingly by an interval tone. As the dis-
tance between vehicle and object decreases,
the intervals between the tones become
shorter. If the distance to the nearest object
falls to below roughly 1 ft/30 cm, then a contin-
uous tone sounds.
An interval tone is interrupted after approx.
3seconds:>If you remain in front of an object that has
been detected by only one of the corner
sensors
>If you are driving parallel to a wall
Malfunction
The indicator lamp in the instrument
cluster comes on. PDC is malfunc-
tioning. A message appears on the
Control Display. Have the system checked.
To avoid this problem, keep the sensors clean
and free of ice or snow in order to ensure that
they will continue to operate effectively. When
using a high-pressure cleaner, do not direct the
jet toward the sensors for lengthy periods and
only spray from a distance of at least 4 in/10 cm.
PDC with visual warning
You can also have the system show distances
to objects on the Control Display. The contours
of distant objects are shown on the Control Dis-
play even before the acoustic signal sounds.
The setting is stored for the remote control cur-
rently in use.
iDrive, for operating principle refer to page16.
1.Press the button.
This opens the start menu.
2.Press the controller to open the menu.
3.Select "Settings" and press the controller.
4.Select "Vehicle / Tires" and press the con-
troller.
5.If necessary, move the highlight marker to
the uppermost field. Turn the controller

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assistant will no longer hold the car in place
after approx. 2 seconds and the car will start to
roll backwards.<
Flat Tire Monitor FTM*
The concept
The Flat Tire Monitor detects pressure loss in a
tire by comparing the rotating speeds of the
individual tires while moving.
In the event of pressure loss, the rolling circum-
ference changes and, thus, the rotating speed
of the affected wheel. This change is detected
and is reported as a flat tire.
Functional requirement
In order to assure the reliable reporting of a flat
tire, the system must be initialized for the cor-
rect tire inflation pressure.
The system must be reinitialized each
time a tire inflation pressure has been cor-
rected or a wheel or tire has been changed.<
System limitations
The Flat Tire Monitor is unable to warn
the driver of sudden, severe tire damage
caused by external factors, nor can it identify
the gradual loss of pressure that will inevitably
occur in all four tires over a lengthy period of
time.<
In the following situations, the system could be
delayed or malfunction:
>System has not been initialized
>Driving on snowy or slippery road surface
>Performance-oriented style of driving: slip
in the drive wheels, high lateral acceleration
>Snow chains are attached
Initializing the system
The initialization is completed during driv-
ing, which can be interrupted at any time.
When driving resumes, the initialization is con-
tinued automatically.
Do not initialize the system while snow chains
are attached. 1.Press the button.
This opens the start menu.
2.Press the controller to open the menu.
3.Select "Settings" and press the controller.
4.Select "Vehicle / Tires" and press the con-
troller.
5.If necessary, move the highlight marker to
the uppermost field. Turn the controller
until "FTM" is selected and press the con-
troller.
6.Start the engine, but do not start driving.
7.Select "Reset" and press the controller.
8.Select "Yes" and press the controller.
9.Start to drive.
Initialization is completed while the car is on
the move, without any feedback.

Technology for driving comfort and safety
84
Indication of a flat tire
The warning lamps come on in yellow
and red. A message appears on the
Control Display. In addition, a signal
sounds. There is a flat tire or substan-
tial loss of tire pressure.
1.Cautiously reduce speed to below 50 mph/
80 km/h. Avoid sudden braking and steer-
ing maneuvers. Do not exceed a speed of
50 mph/80 km/h.
If the car is not equipped with Run-
Flat Tires, refer to page207, the stan-
dard equipment by design, do not continue
driving. A severe accident could result if you
continue driving after a tire puncture.<
2.At the next opportunity, check the air pres-
sure in all four tires.
If all four tires are inflated to the cor-
rect pressures, the Flat Tire Monitor
might not have been initialized. The system
must then be initialized.<
3.In the event of complete tire pressure loss,
0 psi/0 kPa, you can estimate the distance
for which you can continue driving on the
basis of the following guidelines:
>With a light load:
1 to 2 persons without luggage:
approx. 155 miles/250 km
>With a medium load:
2 persons, cargo bay full, or 4 persons
without luggage:
approx. 90 miles/150 km
>With a full load:
4 persons, cargo bay full:
approx. 30 miles/50 km
Drive cautiously and do not exceed a
speed of 50 mph/80 km/h, otherwise
there is a risk of an accident. In the event of
pressure loss, vehicle handling changes.
This includes reduced tracking stability in
braking, extended braking distance and
altered natural steering characteristics.
If unusual vibration or loud noises occur
during the journey, this may be an indication
that the damaged tire has finally failed.
Reduce your speed and pull over as soon as possible at a suitable location. Otherwise
parts of the tire could come loose, resulting
in an accident. Do not continue driving.
Instead, contact your BMW center.<
Malfunction
The warning lamps come on in yel-
low. A message appears on the Con-
trol Display. The Flat Tire Monitor has
a malfunction or has failed. Have the
system checked as soon as possible.
Tire Pressure Monitor TPM*
The concept
TPM checks the inflation pressures of the four
mounted tires. The system notifies you if there
is a significant loss of pressure in one or more
tires.
Functional requirement
In order to assure the reliable reporting of a flat
tire, the system must be reset while all tire infla-
tion pressures are correct.
Always use wheels with TPM electronics. Oth-
erwise, the system may malfunction.
Each time a tire inflation pressure has
been corrected or a wheel or tire has been
changed, reset the system.<
System limitations
TPM cannot warn you in advance of sud-
den severe tire damage caused by out-
side influences.<
The system does not work correctly if it has not
been reset; for example, a flat tire may be indi-
cated even though the tire inflation pressures
are correct.
The system is inactive and cannot indicate a flat
tire if a wheel without TPM electronics, such as
a compact spare wheel, has been mounted, or if
TPM is temporarily malfunctioning due to other
systems or devices using the same radio fre-
quency.

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Status indicator on the Control Display
The color of the tires represents the status of
the tires and the system.
TPM takes into account that tire pressures
change while the vehicle is being driven. The
tire pressures do not need to be corrected
unless the TPM instructs you to do so by means
of color indicators.
Green
The tire inflation pressure corresponds to the
established target value.
"TPM active" appears on the Control Display.
One wheel yellow
There is a flat tire or substantial loss of tire pres-
sure in the indicated tire. A message appears on
the Control Display.
All wheels yellow
There is a flat tire or substantial loss of tire pres-
sure in several tires. A message appears on the
Control Display.
Gray
The system cannot detect a puncture.
Possible reasons for this:
>TPM is being reset
>Temporary malfunction caused by systems
or devices using the same radio frequency
>Malfunction
Resetting the system
Each time a tire inflation pressure has
been corrected or a wheel or tire has been
changed, reset the system.<
iDrive, for operating principle refer to page16.
1.Press the button
The start menu is called up.
2.Press the controller to open the menu.3.Select "Settings" and press the controller.
4.Select "Vehicle / Tires" and press the con-
troller.
5.If necessary, move the highlight marker to
the uppermost field. Turn the controller
until "TPM" is selected and press the con-
troller.
6.Start the engine, but do not start driving.
7.Select "Reset" and press the controller.
8.Select "Yes" and press the controller.
9.Start to drive.
The tires are shown in gray and "Resetting
TPM..." is displayed.
After driving a few minutes, the set inflation
pressures in the tires are accepted as the target
values to be monitored. The system reset is
completed during your drive, and can be inter-
will be adapted
will be adapted

Technology for driving comfort and safety
86 rupted at any time. When driving resumes, the
reset is continued automatically. On the Control
Display, the tires are shown in green and "Sta-
tus: TPM active" is displayed again.
If a flat tire is detected while the system is
resetting and determining the inflation
pressures, all tires on the Control Display are
displayed in yellow. The message "Tire low!" is
shown.<
Message for low tire inflation pressure
The warning lamps come on in yellow
and red. A message appears on the
Control Display. In addition, a signal
sounds. There is a flat tire or substan-
tial loss of tire pressure.
1.Cautiously reduce speed to below 50 mph/
80 km/h. Avoid sudden braking and steer-
ing maneuvers. Do not exceed a speed of
50 mph/80 km/h.
If the car is not equipped with Run-
Flat Tires, refer to page207, the stan-
dard equipment by design, do not continue
driving. Otherwise a severe accident could
result after a tire puncture if you continue
driving.<
2.In the event of complete pressure loss,
0 psi/0 kPa, you can estimate the possible
distance for continued driving on the basis
of the following guidelines:
>With a light load:
1 to 2 persons without luggage:
approx. 155 miles/250 km
>With a medium load:
2 persons, cargo bay full, or 4 persons
without luggage:
approx. 95 miles/150 km
>With a full load:
4 persons, cargo bay full:
approx. 30 miles/50 km
Drive cautiously and do not exceed a
speed of 50 mph/80 km/h. In the event of
pressure loss, vehicle handling changes. This
includes reduced tracking stability in braking,
extended braking distance and altered natural
steering characteristics.If unusual vibration or loud noises occur during
the journey, this may be an indication that the
damaged tire has finally failed. Reduce your
speed and pull over as soon as possible at a
suitable location. Otherwise parts of the tire
could come loose, resulting in an accident. Do
not continue driving. Instead, contact your
BMW center.<
Malfunction
The small warning lamp flashes in
yellow and then lights up continu-
ously; the larger warning lamp comes
on in yellow. On the Control Display,
the tires are shown in gray and a message
appears. No punctures can be detected.
This type of message is shown in the following
situations:
>If there is a malfunction
Have the system checked.
>If a wheel without TPM electronics has
been mounted
>If TPM is temporarily malfunctioning due to
other systems or devices using the same
radio frequency.
Message for unsuccessful system
reset
The warning lamp lights up yellow. A
message will appear on the Control
Display. The system is not reset after
a tire has been changed, for example.
Check the tire inflation pressure and reset the
system, refer to page85.
Declaration according to NHTSA/
FMVSS 138
Tire Pressure Monitoring Systems
Each tire should be checked monthly when cold
and inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or tire inflation pressure label. If
your vehicle has tires of a different size than the
size indicated on the vehicle placard or tire infla-
tion pressure label, you should determine the
proper tire inflation pressure for those tires. As
an added safety feature, your vehicle has been

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equipped with a tire pressure monitoring sys-
tem, TPMS, that illuminates a low tire pressure
telltale when one or more of your tires are signif-
icantly under-inflated. 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 han-
dling and stopping ability. Please note that the
TPMS is not a substitute for proper tire mainte-
nance, and it is the driver’s responsibility to
maintain correct tire pressure, even if underin-
flation has not reached the level at which the
TPMS low tire pressure telltale illuminates.
The TPMS malfunction indicator is combined
with the low tire pressure telltale. When the sys-
tem detects a malfunction, the telltale will flash
for approximately one minute and then remain
continuously lit. This sequence will continue
upon subsequent vehicle startups 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
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.
Active steering*
The concept
Active steering varies the turning angle of the
front wheels in relation to steering wheel move-
ments. It also varies the steering force required
to turn the wheels depending on the speed at
which you are driving.
When you are driving in the low road-speed
range, e.g. in a town or when parking, the steer-
ing angle increases, i.e. the steering becomes very direct, and less effort is required to turn the
wheels. In the higher speed range, on the other
hand, the steering angle is reduced more and
more. This improves the handling capability of
your BMW over the entire speed range.
In critical situations, the system can make tar-
geted corrections to the steering angle pro-
vided by the driver and thus stabilize the vehicle
before the driver intervenes. This stabilizing
intervention is simultaneously deactivated
when DSC is switched off, refer to page81.
Malfunction
The warning lamps come on. Active
steering is no longer operational. At
low speeds, greater steering wheel
movements are required, whereas at
higher speeds the vehicle reacts more sensi-
tively to steering wheel movements. The stabil-
ity-enhancing feature may also be deactivated.
Drive cautiously and think well ahead. Have the
system checked.
Brake Force Display*
On the left: normal braking.
On the right: sharp braking

Things to remember when driving
114
Things to remember when driving
Break-in period
Moving parts need breaking-in time to adjust to
each other. Please follow the instructions below
in order to achieve the optimal service life and
economy of operation for your vehicle.
Engine and differential
Always obey all official speed limits.
Up to 1,200 miles/2,000 km
Drive at varying engine and road speeds, but do
not exceed an engine speed of 4500 rpm or a
road speed of 100 mph/160 km/h.
Avoid full-throttle operation and use of the
transmission's kick-down mode.
After driving 1,200 miles/2,000 km
Engine and vehicle speeds can be gradually
increased.
Tires
Due to technical factors associated with their
manufacture, tires do not achieve their full trac-
tion potential until after an initial break-in
period. Therefore, drive cautiously during the
first 200 miles/300 km.
Brake system
Brakes require an initial break-in period of
approx. 300 miles/500 km to achieve optimized
contact and wear patterns between brake pads
and rotors. Drive cautiously during this break-in
period.
Clutch
The function of the clutch reaches its optimal
level only after a distance driven of approx.
300 miles/500 km. During this break-in period,
engage the clutch gently.
Following part replacement
The same break-in procedures should be
observed if any of the components mentioned
above have to be renewed in the course of the
vehicle's operating life.
Saving fuel
The fuel consumption of your vehicle depends
on several factors. You can lower fuel consump-
tion and the environmental impact by taking
certain measures, adjusting your driving style
and having the vehicle serviced regularly.
Remove any unneeded cargo
Additional weight increases fuel consumption.
Remove any mounted parts after you
have finished using them
Remove unneeded additional mirrors, the roof
rack and the rear luggage rack after use.
Mounted parts affect the vehicle's aerodynam-
ics and increase fuel consumption.
Close the windows and glass roof
An open glass roof or window causes higher air
resistance and thus increases fuel consump-
tion.
Check tire inflation pressure regularly
Check the tire inflation pressure at least twice a
month and before embarking on a long journey,
and correct it if necessary.
Low tire inflation pressure causes higher rolling
resistance and thus increases fuel consumption
and tire wear.
Set off immediately
Do not let the engine warm up while the car is
still standing, but set off immediately at moder-
ate engine speed. This is the fastest way for the
cold engine to reach its operating temperature.

Things to remember when driving
116 The risk of hydroplaning increases with declin-
ing tread depth on the tires, refer also to Mini-
mum tread depth on page206.
Driving through water
Drive through water on the road only if it is
not deeper than 1 ft/30 cm, and then only
at walking speed at the most. Otherwise, the
vehicle's engine, the electrical systems and the
transmission may be damaged.<
Use the parking brake on inclines
On inclines, do not hold the vehicle for a
lengthy period using the clutch; use the
parking brake instead. Otherwise greater clutch
wear will result.<
For more information about the drive-off assis-
tant, refer to page82.
Braking safely
Your BMW is equipped with ABS as a standard
feature. Applying the brakes fully is the most
effective way of braking in situations in which
this is necessary. Since the vehicle maintains
steering responsiveness, you can still avoid
possible obstacles with a minimum of steering
effort.
Pulsation of the brake pedal, combined with
sounds from the hydraulic circuits, indicate that
ABS is in its active mode.
Driving in wet conditions
When roads are wet or there is heavy rain,
briefly exert gentle pressure on the brake pedal
every few miles. Monitor traffic conditions to
ensure that this maneuver does not endanger
other road users. The heat generated in this
process helps dry the pads and rotors to ensure
that full braking efficiency will then be available
when you need it.
Hills
To prevent overheating and the resulting
reduced efficiency of the brake system,
drive long or steep downhill gradients in the
gear in which the least braking is required. Even
light but consistent brake pressure can lead to high temperatures, brake wear and possibly
even brake failure.<
You can increase the engine's braking effect by
shifting down, all the way to first gear if neces-
sary. This strategy helps you avoid placing
excessive loads on the brake system. Down-
shifting in manual mode of the automatic trans-
mission, refer to page61.
Never drive with the clutch held down,
with the transmission in idle or with the
engine switched off; otherwise, engine braking
action will not be present or there will be no
power assistance to the brakes or steering.
Never allow floor mats, carpets or any other
objects to protrude into the area around the
pedals, otherwise pedal function could be
impaired.<
Corrosion on brake rotors
When the vehicle is driven only occasionally,
during extended periods when the vehicle is not
used at all, and in operating conditions where
brake applications are less frequent, there is an
increased tendency for corrosion to form on
rotors, while contaminants accumulate on the
brake pads. This occurs because the minimum
pressure which must be exerted by the pads
during brake applications to clean the rotors is
not reached.
Should corrosion form on the brake rotors, the
brakes will tend to respond with a pulsating
effect that even extended application will fail to
cure.
When the vehicle is parked
Condensation forms while the automatic cli-
mate control is in operation, and then exits
under the vehicle. Traces of condensed water
under the vehicle are therefore normal.
Before driving into a car wash
For general information about taking care of
your BMW, refer to the Caring for your vehicle
brochure.