Chevrolet 2007 Avalanche Owner's Manual page 84

Restart the vehicle and have the person remain in
this position for about two minutes. This will
allow the system to detect that person and then
enable the passenger's airbag.
84
CAUTION:
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If the airbag readiness light in the
instrument panel cluster ever comes on
and stays on, it means that something
may be wrong with the airbag system. If
this ever happens, have the vehicle
serviced promptly, because an adult-size
person sitting in the right front
passenger's seat may not have the
protection of the frontal airbag. See
Airbag Readiness Light on page 242 for
more on this, including important safety
information.
Aftermarket equipment, such as seat covers, can
affect how well the passenger sensing system
operates. You may want to consider not using seat
covers or other aftermarket equipment if your
vehicle has the passenger sensing system. See
Adding Equipment to Your Airbag-Equipped
Vehicle on page 86 for more information about
modifications that can affect how the system
operates.