BMW GRAN COUPE 4 Series Owner's Manual page 128

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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
Concept
The system detects tire inflation pressure loss
on the basis of rotation speed differences be‐
tween the individual wheels while driving.
In the event of a tire inflation pressure loss, the
diameter and therefore the rotational speed of
the corresponding wheel changes. The differ‐
ence will be detected and reported as a flat
tire.
The system does not measure the actual infla‐
tion pressure in the tires.
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Safety
Online Edition for Part no. 01402978272 - II/17
Functional requirements
The system must have been initialized when
the tire inflation pressure was correct; other‐
wise, reliable flagging of a flat tire is not as‐
sured:
▷ After a tire or wheel replacement, an initial‐
ization was performed with the correct tire
inflation pressure.
▷ After the tire inflation pressure was ad‐
justed to a new value, an initialization was
performed.
Status display
The current status of the flat tire monitor can
be displayed, for example, whether the RPA is
active.
About iDrive:
1. "My Vehicle"
2. "Vehicle status"
3. "Flat Tire Monitor"
The status is displayed.
Initialization required
An initialization must be performed in the fol‐
lowing situations:
▷ After the tire inflation pressure has been
adjusted.
▷ After a tire or wheel replacement.
Performing initialization
When initializing, the set tire inflation pres‐
sures serve as reference values in order to de‐
tect a flat tire. Initialization is started by con‐
firming the tire inflation pressures.
Do not initialize the system when driving with
snow chains.
Using iDrive:
1. "My Vehicle"
2. "Vehicle status"
3. "Flat Tire Monitor"