BMW 550i xDrive Sedan 2014 - Manual (Page 109)

due to driving or because of the heat of the
Sun, the tire inflation pressure increases also.
The tire pressure is reduced when the tire
temperature falls again. This behavior may
cause a warning to be issued if temperatures
fall very sharply.
Malfunction
The yellow warning lamp flashes and
then lights up continuously. A Check
Control message is displayed. No flat
tire or loss of tire pressure can be detected.
Display in the following situations:
▷ A wheel without TPM electronics is fitted:
have the service center check it if neces‐
sary.
▷ Malfunction: have the system checked by
your service center.
▷ TPM was unable to complete the reset.
Reset the system again.
▷ Disturbance by systems or devices with
the same radio frequency: after leaving the
area of the disturbance, the system auto‐
matically becomes active again.
Declaration according to NHTSA/
FMVSS 138 Tire Pressure Monitoring
System
Each tire, including the spare (if provided)
should be checked monthly when cold and in‐
flated to the inflation pressure recommended
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 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 pres‐
sure telltale when one or more of your tires is
significantly 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 pres‐
sure. Driving on a significantly under-inflated
tire causes the tire to overheat and can lead to
tire failure. Under-inflation also reduces fuel ef‐
ficiency 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 under-inflation 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 indi‐
cator to indicate when the system is not oper‐
ating properly. The TPMS malfunction indica‐
tor is combined with the low tire pressure
telltale. When the system detects a malfunc‐
tion, the telltale will flash for approximately one
minute and then remain continuously illumi‐
nated. This sequence will continue upon sub‐
sequent 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 replace‐
ment or alternate tires or wheels on the vehicle
that prevent the TPMS from functioning prop‐
erly. Always check the TPMS malfunction tell‐
tale 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.
FTM Flat Tire Monitor
The concept
The system detects a pressure loss on the ba‐
sis of speed differences between the individual
wheels while driving.
In the event of a pressure loss, the diameter
and therefore the rotational speed of the corre‐
sponding wheel change. This is detected and
reported as a flat tire.
Seite 109
Safety Controls
109
Online Edition for Part no. 01 40 2 928 000 - II/14