if the stereo has been changed or someone has had the dash out then they could of trapped the ribbon cable that links to the heater control unit. Yes you can check it yourself. Check in the guides section. Probably look for changing stereo thread and it will show you how to get to it
CAI intakes are more for sound than anything else. Best in terms of performance is OEM 06 onwards airfilter panel box with a upgraded panel filter like a K&N
certainly looks like a uk spec car. I reckon its from Ireland. Have seen that some Irish zeds do have some differences like phone kit not standard for example
For those who were asking for the code which had expired, Its now working. Just spoken to a helpful Hannah at Autobulbs Direct and the discount code has been reinstated. So 10% off is now available