Airbag light & horn not working

[Littleginge]

Hi I wonder if anyone can help me , my mum has got a 1996 1.0 K11 , I have converted it to power steering with the donor car being a 1998 model but the problem I now have is the Airbag Light is on & the horn doesn't work since I converted it . I have got a diagnostic tool but it won't read anything, has anyone got any ideas as nothing got touched on the column or steering wheel end !