Pontiac Vibe 2007 Owner's Manual page 331

This light also comes on for a few seconds and
then go off when you turn the ignition to ON. This
indicates that the TPMS is functioning properly.
If the low-tire pressure warning light comes
on while driving your vehicle, the system may
have detected a low-tire condition. You need to
stop as soon as possible and check your tires
for damage. If a tire is flat, see If a Tire Goes Flat
on page 342 and Changing a Flat Tire on
page 343. Also check the tire pressure in all four
tires, and set them to the specified level shown
on the Tire and Loading Information label.
This light, on the
instrument panel cluster,
comes on when the
tire pressure monitoring
system detects a
low-tire condition.
See Inflation - Tire Pressure on page 329 and
Loading Your Vehicle on page 253 for additional
information.
Note: The tire pressure monitoring system on your
vehicle warns you when one of the tires is
significantly under-inflated and when some
combinations of the tires are significantly
under-inflated. However, there are other
combinations of significantly under-inflated tires for
which the tire pressure monitoring system might not
give a warning. These other combinations are
relatively common, accounting for approximately
half the instances in which vehicles have
significantly under-inflated tires. For example, the
system might not warn you when both tires on the
same side or on the same axle of your vehicle are
significantly under-inflated. It is particularly
important, therefore, to check the tire pressure in all
of the tires regularly and maintain proper pressure.
In order for the tire pressure monitoring system to
work properly you need to reset (initialize) the
tire pressure monitoring system. Any time
you check and/or adjust a tire's pressure, repair or
replace a tire or wheel, or rotate the tires the
tire pressure monitor system needs to be reset.
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