I actually own the same car, and although I never had this happen to it, it started doing the same thing in my 2001 Civic. The only thing I had on the passengers seat was my lunch and some mail, weighing all of 3 pounds. The only thing I did was to throw my lunch on the floor and the light never came back on. Do you have anything of weight on the seat all the time? I was surprised that it didn't take much to set mine off.