if its the air bag in the seat itself, remove all the plastic trim pieces from around the base on the door side. there should be a bunch of plugs going into some sockets, clipped onto a white adaptor. easier to get at if you undo the 4 seat bolts with a torx bit. check for a yellow plug, on airbag seats i believe it has wires for the airbag itself, on non airbag cars it has a small wire loop to close the circuit. make sure that is plugged in properly. i had to find one with a loop to stop the airbag light on a ba mark 2 that was stock without airbag seats, that i put a fairmont ghia set of seats into that had airbags. otherwise, when you start your car, count the number of flashes the light does (3 flashes pause 2 flashes would be 32 for example) someone here may then be able to provide an idea on the fault code