GMC Sierra Denali Owner's Manual page 157

If the right front passenger's air bag is turned
off for a person who isn't in a risk group
identified by the national government, that
person won't have the extra protection of an
air bag. In a crash, the air bag wouldn't be able
to inflate and help protect the person sitting
there. Don't turn off the passenger's air bag
unless the person sitting there is in a risk
group. See "Air Bag Off Switch" in the Index
for more on this, including important safety
information.
If, after several seconds, all status indicator lights
remain on, or if there are no lights at all, there may be a
problem with the lights or the passenger sensing
system. See your dealer for service.
If the air bag off indicator and the air bag
readiness light ever come on together, it
means that something may be wrong with the
air bag system. If this ever happens, have the
vehicle serviced promptly, because an
adult-size person sitting in the right front
passenger seat may not have the protection of
the air bag. See "Air Bag Readiness Light" in
the Index.
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