Required tire inflation pressure check
message
A Check Control message is displayed in the
following situations▷The system has detected a wheel change,
but no reset was done.▷Inflation was not carried out according to
specifications.▷The tire inflation pressure has fallen below
the level of the last confirmation.
In this case:
▷Check the tire pressure and correct as
needed.▷Carry out a reset of the system after a tire
change.
System limits
The system does not function properly if a re‐
set has not been carried out, e.g., a flat tire is
reported though tire inflation pressures are
correct.
The tire inflation pressure depends on the
tire's temperature. Driving or exposure to the
sun will increase the tire's temperature, thus
increasing the tire inflation pressure. The tire
inflation pressure is reduced when the tire
temperature falls again. These circumstances
may cause a warning when 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 inflation pressure can be de‐
tected.
Display in the following situations:
▷A wheel without TPM electronics is fitted:
have the service center check it if needed.▷Malfunction: have the system checked by
your service center.▷TPM was unable to complete the reset.
Reset the system again.▷Interference through systems or devices
with the same radio frequency: after leav‐
ing the area of the interference, the system
automatically 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‐
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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 conceptThe system detects tire inflation pressure losson 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. This will be
detected and reported as a flat tire.
The system does not measure the actual infla‐
tion pressure in the tires.
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. Initialize the system after each correc‐ tion of the tire inflation pressure and after
every tire or wheel change.
Status display
The current status of the Flat Tire Monitor can
be displayed on the Control Display, e.g.,
whether or not the FTM is active.
On the Control Display:1."Vehicle info"2."Vehicle status"3. "Flat Tire Monitor (FTM)"The status is displayed.
Initialization
When initializing the once set inflation tire
pressures serve as reference values in order to
detect a flat tire. Initialization is started by con‐
firming the tire inflation pressures.
Do not initialize the system when driving with
snow chains.
On the Control Display:1."Vehicle info"2."Vehicle status"3. "Perform reset"4.Switch on drive readiness – do not drive
off.5.Start the initialization with "Perform reset".6.Drive away.
The initialization is completed while driving,
which can be interrupted at any time.
The initialization automatically continues when
driving resumes.
Indication of a flat tire The yellow warning lamp lights up. A
Check Control message is displayed.
There is a flat tire or a major loss in tire
inflation pressure.
1.Reduce your speed and stop cautiously.
Avoid sudden braking and steering maneu‐
vers.2.Identify the damaged wheel. Do so by
checking the tire inflation pressure using
the Mobility System. If the tire inflation
pressure in all tires is correct, the Flat Tire
Monitor may not have been initialized. In
this case, initialize the system.3.Repair flat tire with the Mobility System, re‐
fer to page 178, or replace the damaged
wheel.
If a Mobility System is not available, contact
the service center.
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