Had something similar happen to mine a few weeks ago. While the truck was parked and running we were looking for my phone and my wife pulled the passenger seat slide lever from outside the truck (so she could look behind and under the seat) and the seat flew forward, ever since then my airbag light and service air bag system message would display sometimes the chime would go off too. Long story short , i got out my odb scanner and hooked it up and got 3 codes B0052-9A Pass seatbelt sensor, B2734-12 Pass occupant detection sensor-circuit short to bat and B0052-13 Pass seat belt sensor - circuit open. This gave me a starting point to look at, checked all the plugs and even took the seat belt buckle pn#P1WW991X9AC out and inspected it, of course this involved unbolting the pass seat and moving it backwards to access the bolt and since i was messing with airbag connectors i did undo my battery for a time before working on it. Didn't find any noticeable problems so i put it all back together and ran the scanner which is able to clear the SRS Codes on my dash but still shows them in the truck system but the are Stored now not Active and the lights message and chime don't show anymore and the seatbelt light and airbag light do their normal stuff at startup and when i have a passenger. My theory is it was probably a loose or bad connection and when the seat slammed forward with nobody sitting in it it triggered some codes to be set by the computer and since i took the seat loose and unplugged everything and undid the battery too it cleared it up. So yea check all the plugs, the seatbelt buckle is a small gray plug and if you have access to a ODB Scanner it can help. Good Luck!