GMC SIERRA 2002 Manual page 33

The system checks the air bag electrical system for
malfunctions. The light tells you if there is an electrical
problem. See "Air Bag Readiness Light" in the Index
for more information.
1-26
There is an air bag readiness
light on the instrument
panel, which shows the air
bag symbol.
How the Air Bag System Works
Where are the air bags?
The driver's air bag is in the middle of the
steering wheel.