GMC 2008 Acadia - Manual (Page 185)

{ CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not inflate in a crash, or they
could even inflate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the airbag readiness light
stays on after you start your vehicle.
The airbag readiness light should flash for a few seconds
when you start the engine. If the light does not come
on then, have it fixed immediately. If there is a problem
with the airbag system, an airbag Driver Information
Center (DIC) message may also come on. See DIC
Warnings and Messages on page 3-66 for more
information.
Passenger Airbag Status Indicator
Your vehicle has the passenger sensing system. Your
instrument panel has a passenger airbag status indicator.
When you start the vehicle, the passenger airbag status
indicator will light ON and OFF, or the symbol for on
and off, for several seconds as a system check. If you
use remote start to start your vehicle from a distance,
if equipped, you may not see the system check.
United States Canada
3-43