First discovery problems

Hi, I've just bought my first discovery and have a few problems!! The rear wiper doesn't work and the intermittent option on the front is very sporadic. Also mine has been converted back to springs but the box for the air suspension still makes a ticking noise, is this likely to cause problems?

I'm not sure about the wipers but if the air suspension computer has a isolator (to tell the computer the 'air suspension' is running all good) I imagine that it should be running OK. But if there's no isolator then you may get into problems. I'm no D2 expert tho so I don't take this advice without someone telling me whether I'm correct or not)