Chevrolet 2002 Tahoe Owner's Manual page 161

CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags 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 air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to RUN. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.
Voltmeter
United States
When your engine is not running, but the ignition is in
RUN, this gage shows your battery's state of charge in
DC volts.
When the engine is running, the gage shows the
condition of the charging system. Readings between
the low and high warning zones indicate the normal
operating range.
Canada
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