I don't know how I'd find that out, without removing the centre console section?
The control unit located under a false floor in the big box behind the passenger seat.
Very easy to access the unit: go into the box, lift up a big square cover on the box floor (you'll see it straight away - its sits proud of the box floor and fills the whole box). Under this there is a smaller tray (kind of looks like a coin tray), all you need is to lever this up with something like a small screwdriver or a key it takes very, very little force to bring this up. The control unit is fixed to the bottom of this tray.