Aircon problem please help.

Hi sorry if I have duplicated this thread from the wrong part of the forums, I pretty poor at this.
I run an 08 Micra Acenta, when I turn on the manual aircon it blows ice cold cold on the passenger side and warm on the driver's side. Any help with this would be gratefully received.
splitting the air flow in this way is difficult as the blower has a vane (air mixer door apparantly) which changes the routing in the air box from the warm air heat exchanger to the cold air exchanger as a single unit rather than being split to either side.
for it to be doing what it is doing would suggest that it's moving but not fully, leaving an passage for warm air one one side which you are feeling on the vent.
you aren't going to like this, but it's a complete bitch to get at requiring most of the dash to be removed. upi can check the arm without removing everything by popping the glove box out.

perhaps start with the easy thing and check the pollen filter. it's not this, but it wouldn't hurt. :)