Without scanning it you wont know whats causing the light to flash but you can try this.
Make sure the ignition is switched OFF & the key is out of the ignition, wait 5 minutes & then have a look under EACH front seat, you will see a orange connector with 2 wires, unplug this & spray a little electrical contact cleaner ( or WD40 if thats handy ) into each half, then plug & unplug the conector a few times.
Then move onto the other front seat & repeat, that normally sorts out 306 / Xsara flashing airbag lights.
Lee, June 2007
