Just wanted to help anyone else that has this problem. I have a 2004 XJR that the airbag light would intermittently go off and on. It was very random and would come on about 1/2 the time when I would dirve the car. I took it to the jag dealer and they checked the code-- it said open circuit in the driver or passenger seat... they said it would cost more to tear into it and find the problem. So I took it home and unbolted the driver's seat and leaned it back to check it out (the passenger seat is rarely used). I discovered that 3 of the appx 6 or 7 wire harnesses were detached from the plastic plate on the bottom of the seat (possibly from going back and forth so many times). The wire harnesses were being mangled, twisted, and rolled around under the seat every time it moved when you got in and out of the car. I untwisted and reattached the harnesses (which I want to be clear were not unplugged, just twisted) to the plasic mounting plate under the seat. The airbag light never came on again. My thought is the wires were being stretched or pulled from the harnesses or the harnesses themselves were being pulled on and this triggered the light. One note: you will need torx bits and reverse torx bits to unbolt the seat-- there is one bolt in the front and two in the rear. Hope this helps.

 

Ours has just come on. This is very useful information and will have to investigate. Thanks.

 

Not a problem-- good luck and hope you figure it out.