Something strange in the neighborhood...or under the hood?

[DemiSheep]

I need help! My wife and I got in our 2009 Chevy Aveo tonight to go somewhere and when I turned on the car, the tone you normally hear telling to buckle up kept on making the noise well after we had buckled up. Then we heard a very extremely high picked electronic noise which stayed on continuously as we drove.

The only things I can say are, 1, the car just came due for an oil change. 2, the oil change light is on, but it's been on since I had the last oil change because I forgot how to turn it off which I now read in the manual how to do.

Once we got back into the car to return home the same thing happened.

Any ideas?

Respectfully,
DemiSheep

[petrified.rabbit]

could almost be the switch in the belt buckle getting stuck faking a short? or a wire for that system is shorted?

where was the noise coming from? ever spill a drink, get the interior wet etc?