I decided a DIY fix after the horn on my 1.4 16v fabia stopped working and a main agent quoted me £195 for fixing it by replacing the entire steering wheel assembly. I disconnected the battery and removed the airbay, found the horn contacts had corroded and removed it with a little light sandpapering, temporary reconnected the battery and checked everthing worked then disconnected it again reasssembled everything and it worked 1st time, problem is now the airbay light is on constantly, is there a fault with it? or do i need to get ther dealer involved and hope they dont take me for a mug.

you need to get airbag light sorted because when the lights on and you crash the airbag wont work!

You have disconnected the airbag, so it will need the fault clearing.