Chevrolet 2004 Express Van Owner's Manual page 80

CAUTION:
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If the air bag readiness light ever comes on
when you have turned off the air bag, it means
that something may be wrong with the air bag
system. The right front passenger's air bag
could inflate even though the switch is off. If
this ever happens, don't let anyone whom the
national government has identified as a
member of a passenger air bag risk group sit
in the right front passenger's position (for
example, don't secure a rear-facing child
restraint in your vehicle) until you have your
vehicle serviced.
1-74
To turn the right front passenger's air bag on again,
insert your ignition key into the switch, push in,
and move the switch to the on position.