My central locking works off the button on the inside of the drivers door but not when using the key in the external lock. The key fob doesn't work - I was told that damp has probably got into the control box so I need to change it. Thanks Audi......great design.....NOT!

Anyhow, I was told it's probably the micro switch? How much are these, where is it located and what's the best way to go about changing it?

Cheers