Hi Annette, the rough road will not of affected it, if the car has seatbelt pre-tensioners, have a look at the wiring under the seats (all cased in yellow sleeving) as constant back & forward adjustments of the seats can pull on the connections and cause the problem you have, the otherthing is the spring connections from the steering wheel airbag to the fixed steering column, or it could just be the airbag module has in internal fault.
nigel, July 2008