When I start my 02 Ranger it beeps?

[pr0phet]

I started up my 02 ranger today and it started beeping at me. There are no dash lights lighting up or anything. I've had the truck a month so I thought hey maybe it's because i'm low on gas. So I filled up my tank and it still kept beeping at me. Anyone have any idea what it means? I can't figure out what it is, but it beeped a good 3-5 minutes before it would stop...

Do you think a light is burned out on the dash?? It seems like this should be so simple to figure out and I can't believe I have to ask a question like this.

[Dasbogie]

Were you wearing your seatbelt?

[pr0phet]

Yep...

It beeps 5 times in a row, pauses, then does it over and over again for probably 5 times or so.

I've looked around online and found others with the same thing, but nobody knows what the vehicle is saying. One guy had this beep in his mustang but that was because he had no air bags...i am fairly certain that isn't the case here...

I just don't know why there are no light indicators turning on...