Air bag fault light

Hi I had a lot of trouble with my ignition switch. Finally got stuck and had to get recovered home. I managed to get a new lock barrel and fitted it. What a pig that was! Anyway, now the air bag fault light comes on. I'm pretty sure its something I did because it wasn't on before. I tried some Contralube gel on the contacts but still the same. anyone know how to reset this fault. I have a Maxiscan code reader, but cannot find the socket for this. Is there one on a 07 Touran?
Mike