(Owner Manual Page 2-68)
The passenger sensing system turns off the right front
passenger frontal airbag and seat-mounted side
impact airbag under certain conditions. The driver
airbags and the roof-rail airbags are not affected by the
passenger sensing system.
The passenger sensing system works with sensors that
are part of the right front passenger seat. The sensors
are designed to detect the presence of a properly-seated
occupant and determine if the right front passenger
frontal airbag and seat-mounted side impact airbag
should be enabled (may inflate) or not.
I'm not sure if a purse or other light weight objects would activate the passenger airbag but if your display is showing random passenger activation it would be best to have a qualified dealer check into it...better safe than sorry.