Hi, I've got a 2000my Octavia 2.0 auto (8 valve petrol engine) RH drive (brought down here from UK) as a runabout. The aircon doesn't work. It's been checked by a 'specialist' who tells me everything is ok except when tracing the wiring circuit through they discovered that the main control box(?) is defunct. They tell me it's situated under the battery tray. Has anyone ever heard of this before? Does such a thing exist and if so, how do I identify it? I have removed the battery and tray and looked and there is a large black plastic electrical component situated under there, difficult to get at (aren't they always!) with lots of electrical cables going in to and out of it, but I don't know if that's what I'm looking for or not. Any help you can give me would be greatly appreciated. Thank you.

That box is the Fan control unit and it switches the power to the magnetic clutch unit on the AC compressor, item #20 in this http://skoda.7zap.com/en/cz/octavia/oct/2000-202/9/937-937030/#20