Exchange stock update.
The following motor modules are packed and ready for rapid dispatch, all for RHD cars:
Fabia Mk1 - 6Y2959802
Fabia Mk2 - 6Y1959801
Roomster - 6Y1959801
Polo 9N/9N3 - 6Y1959801 (just front elec windows)
Polo 9N/9N3 - 6Y1959801A (all 4 elec windows)
Transporter T5 - 6Y1959801
I had a bit of a play installing all (but 1) of the physically mountable units in my 9N3 Polo, and confirmed that a 6Y1959801 from a Roomster does not work properly in a Polo, the up/down controls are reversed, and with one-touch operation programmed the window doesn't go all the way up when requested (apporx 30mm shy). I suspect a Fabia mk2 unit will do similar, will check later and add info. Edit: yes, up/down reversed and doesn't make it all the way up when one-touch programmed.
Polo and Transporter modules do seem to be interchangeable with each other according to yesterday's fitment of a T5 module in a 9N3 Polo, although I haven't access to a T5 to try a Polo motor in it. If anyone reading has put a replacement motor from a Polo in a T5 and knows if one-touch operation works properly, I'd be grateful to hear about it. Polo modules are distinguished by having VW240xxxx as the bottom line of the part number label, T5 modules have VW750xxxx instead.
If anyone's curiosity is piqued by the above observation about one-touch closure not working with the mismatched Roomster/Polo situation, I'd be glad of someone putting a tape measure up the rear edge of their Roomster (and Fabia mk2) drivers door window to compare the glass height between seals with that of a 9N3 Polo (which I'll add to this post later) edit: 445mm, on 5-door 9N3 Polo.
Pete