Little bit of DIY on the ‘roach, the squealing air-conditioning and alternator belt has been annoying me for a while so I decided to see about tensioning it.
A brief perusal with my search engine du jour wasn’t much help: it seems that air-conditioning is a bit unusual on the Nissan March/Micra K11 (and with a <1 litre engine that’s hardly surprising), the most common fitment seems to be alternator only, with the belt tension handled by an automatically adjusting idler-tensioner.
Luckily I’d seen where the guy that services the car in my absence adjusted it last time, just not which way it needed to be turned (anti-clockwise to increase tension, clockwise to decrease).
You will need a ratchet handle, long extension, universal joint, short extension and 14mm socket. I also recommend slim-fit but tough work gloves: to steady the universal joint you have to wedge your hand in a confined space with some sharp edges nearby.
The socket can just be seen lower-centre of the right hand picture on the head of the tensioner bolt, with the thread continuing diagonally down to the right.
Take care while doing this because the ratchet handle is close to parts of the braking system and it wouldn’t be good to bugger up that pipework.
Good luck.