Chevrolet 2010 Impala Owner's Manual page 177

This indicates that one or more of the tires is
significantly underinflated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. See
information. Stop and check the tires as soon as it is
safe to do so. If underinflated, inflate to the proper
pressure. See
for more information.
For vehicles with a tire
pressure monitoring
system, this light comes
on briefly when the engine
is started. It provides
information about tire
pressures and the Tire
Pressure Monitoring
System.
for more
This indicates that there may be a problem with the
Tire Pressure Monitor System. The light flashes for
about a minute and stays on steady for the remainder
of the ignition cycle. This sequence repeats with every
ignition cycle. See
for more information.
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation
of the fuel, ignition, and emission control systems.
It ensures that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment.
This light should come on
when the ignition is on,
but the engine is not
running, as a check to
show it is working. If it
does not, have the vehicle
serviced by your dealer.
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