There is a passenger seat belt reminder light near the passenger airbag status indicator. See Passenger Sensing System.

When the vehicle is started, this light flashes and a chime may come on to remind passengers to fasten their seat belt. Then the light stays on solid until the belt is buckled.
This cycle continues several times if the passenger remains or becomes unbuckled while the vehicle is moving.
If the passenger seat belt is buckled, neither the chime nor the light comes on.
The front passenger seat belt reminder light and chime may turn on if an object is put on the seat such as a briefcase, handbag, grocery bag, laptop, or other electronic device. To turn off the reminder light and/or chime, remove the object from the seat or buckle the seat belt.
Driver Seat Belt Reminder Light
Airbag Readiness LightSecuring Child Restraints (With
the Seat Belt in the
Front Seat)
This vehicle has airbags. A rear
seat is a safer place to secure a
forward-facing child restraint. See
Where to Put the Restraint.
In addition, the vehicle has a
passenger sensing system which is
designed to turn off the front
outboard passenger frontal airbag
under certain conditions.
...