OBD II - VAG.COM - connection problems doesn't display trouble codes

Well I have an air bag light on and the passenger air bag off light by the gear shifter is always illuminated. No matter if I have the passenger air bag in the on or off position this light always displays off.

So I tried a few products to self diagnose the problem using the OBD II port. The software used was Auterra scan tool for palm, I tried both their CAN-BUS software and the standard NON CAN-BUS.

It connected to the car but no trouble codes appeared, I also have a service light on and an intermittent left Zeon light. None of these coeds appeared.

my main question is does my 2002 Audi TT 225 Quattro use CAN-BUS or NON CAN-BUS because the Bentley manual says its CAN-BUS but ross-tech.com say CAN wasn't used till 2007? Now the Bentley manual only covers 2000-2006 so I am confused what software and product to purchase next? I have access to Windows OS via boot camp on my Macbook Pro if I require Windows OS instead of Palm

Oh and if anyone has had any of the above problems and can help please also post suggestions.