I also had the service airbag light come on on my 04, it just so happens that I was checking some wires under the seat because my heated seat wasnt staying on but for just a short time what happend with mine is I caused it to come on by disconnecting those wires, I got it to go out by disconnecting the negative battery cable first for about an hour then before I hooked the cable back up I pulled the SIR fuse in the panel under the hood then went ahead with hooking the negative cable up first then I put the fuse back in and that was a week ago and havent had any trouble so far....but If you were just driving down the road and didnt do anything to cause it to come on I agree with these guys I would spend the money and get it checked thats a small price to pay for the piece of mind you would have.