GMC 2004 Sierra 1500 Pickup, Owner'S Manual, Page: 204 / 588

Passenger Air Bag Status Indicator
If your vehicle has the passenger sensing system
your rearview mirror will have a passenger air bag status
indicator.
When the ignition key is turned to RUN or START, the
passenger air bag 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 air bag.
If the word ON or the on symbol is lit on the passenger
air bag status indicator, it means that the right front
passenger’s frontal air bag is enabled (may inflate).
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CAUTION:
If the on indicator comes on when you have a
rear-facing child restraint installed in the right
front passenger’s seat, it means that the
passenger sensing system has not turned off
the passenger’s frontal air bag. A child in a
rear-facing child restraint can be seriously
injured or killed if the right front passenger’s air
bag inflates. This is because the back of the
rear-facing child restraint would be very close
to the inflating air bag. Don’t use a rear-facing
child restraint in the right front passenger’s seat
unless the air bag has been turned off.
Passenger Air Bag Status Indicator – United States
Passenger Air Bag
Status Indicator
– Canada
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