I have no idea why, but the firmware update covered in this thread:
http://jeepcherokeeclub.com/65-elec...t-nav-unit-firmware-update-available-now.html
fixed my Service Airbag System indicator constantly being lit.
I installed the updated firmware yesterday and have not seen the indicator since (and it would always come on within 10 seconds of turning the car on).
Before letting the dealer's service center off the hook though(for the
not quite needed part I have been waiting on for 6 weeks now), I am going to tell them they need to get the release notes and prove to me that a change was made to fix this since it is very evident that no-one appears to know what the heck is going on with this vehicle.