GMC 2009 Sierra - Manual (Page 172)

Safety Belt Reminders
Safety Belt Reminder Light
When the engine is started, a chime will sound for
several seconds to remind people to buckle their safety
belts. The driver safety belt light will also come on
and stay on for several seconds, then it will flash for
several more. You should buckle your seat belt.
This chime and light will be
repeated if the driver
remains unbuckled and the
vehicle is in motion.
See DIC Warnings and Messages on page 3-59 for
more information on driver and passenger safety
belt reminders.
If the driver’s belt is buckled, neither the chime nor the
light will come on.
See Passenger Sensing System on page 1-63 for more
information.
Passenger Safety Belt Reminder Light
Several seconds after the engine is started, a chime
will sound for several seconds to remind the front
passenger to buckle their safety belt. This would only
occur if the passenger airbag is enabled. See Passenger
Sensing System on page 1-63 for more information.
The passenger safety belt light will also come on and
stay on for several seconds, then it will flash for
several more.
This chime and light are
repeated if the passenger
remains unbuckled and
the vehicle is in motion.
If the passenger’s safety belt is buckled, neither the
chime nor the light will come on.
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