Fitting a new Airbag / Deactivation fault
 

I've recently replaced both seatbelt tensioners, driver airbag and passenger airbag, had my airbag modules crash data erased, but the airbag light keeps coming on (even when I reset it with my CAN OBD reader). When I erase it, the light goes off, but then comes bck on a second later. I get a fault code "01578" which means "Airbag Deactivation Warning Lamp: Passender Side (K145)".

I canactivate and deactivate the passenger airbag from within the glovebox, but this doesn't seem to be the issues. I'm wondering when I fitted the airbag whether there's something I should have done with the new airbag like pull a pin out or enable it somehow? I literaly just plugged the new one straight in. Did I miss something?

2007 Audi TT 3.2 Quattro