GMC 2006 Sierra - Manual (Page 215)

Passenger Airbag Status Indicator
If your vehicle has the passenger sensing system, your
rearview mirror will have a passenger airbag status
indicator.
When the ignition key is turned to RUN or START, the
passenger airbag status indicator will light ON and OFF,
or the symbol for on and off, for several seconds as a
system check.
Then, after several more seconds, the status indicator will
light either ON or OFF, or either the on or off symbol to let
you know the status of the right front passenger’s frontal
airbag.
Your vehicle may have a label on your sun visor that
says, “Never put a rear-facing child seat in the front.”
This is because the risk to the rear-facing child is so
great, if the airbag deploys.
{ CAUTION:
Even though the passenger sensing system is
designed to turn off the passenger’s frontal
airbag if the system detects a rear-facing child
restraint, no system is failsafe, and no one can
guarantee that an airbag will not deploy under
some unusual circumstance, even though it is
turned off. We recommend that rear-facing
child restraints be secured in the rear seat,
even if the airbag is off.
Never put a child in a rear-facing child restraint in the right
front passenger seat the unless passenger airbag status
indicator shows off.
Passenger Airbag Status Indicator – United States
Passenger Airbag Status Indicator – Canada
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