Well thanks Mellis 46 for the reply and you're right on all accounts.
1. yes that brown and yellow wire is the live from the horn and the horn does work , albeit only a single unit.
2. the cowls on the replacement are quite different to what I've been trying to fit with a non airbag wheel.
3.Definitely no Airbag light.
4.Nothing behind the wheel for the airbag plug to connect into , unless its all been removed at some time.
5. My old Audi wheel fits ok altho' was a bit of fiddling required to get the wire feed tag out of the way when replacing the wheel. However, I now have a steering wheel AND a horn.
Head scratching time as this car was MOT'd only last April and yet has so many "issues" that it makes one wonder at how it could have passed. Two brake hoses with cuts in them, perrished return fuel line, no horn, one washer nozzle completely blocked,high level brake light missing three bulbs, these can't all have appeared in the past 4 months surely!
the result finally....
