I want to know what this problem is; I have a feeling it is something to do with the seatbelt, but I just do not know what.

Okay, when I a m driving the light that let you know that your seat belts are not on keep flashing on and off. I locked all the seatbelts in the car and it was still occuring, so what I am trying to find out is why is this happening. I have a feeling that it is sensor, but where can I locate the sensor

Where your seatbelt hooks up, the senor is in there. If it goes bad, then you will get the reading that your not using it.
It's not normal, but sometime the wire comes off. But I'd say you have to replace.
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP002.jpg

So the sensor is inside the seat belts or they are located somewhere else

It's in the "lock" for the seat belt.
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP004.jpg

Okay I found it, thanx a whole lot; it is located right in the seatbelt. Damn I am learning a lot about these Pontiac's

Have a happy and safe Christmas.
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