Originally Posted by
Disco-tastic
To clarify the D3/4 system, the base system has front vents and vents in the rear of the centre console, and I believe some foot vents under the front seats. These all share the same fan and condenser.
Adding rear aircon gives roof mounted vents and controls to the second row, and pillar mounted vents to the 3rd. Can be synced with the main controls or controlled independently from the roof controls in the second row for temp and fan speed. Has a separate fan motor and condenser in the left rear quarter panel.
In regards to the OP, in my experience a "zone" is somewhere which the temperature can be individually set, not necessarily the fan speed. If the rear seats can determine their own temp that could be considered a zone, if if there's only one fan unit for the entire vehicle.
That said my experience is limited to my D3 and some other cars that cost far less than $130k.