But the battery is brand new (well 1 month old)

Just been out to the car and low and behold the air conditioning is on but i have the key in my pocket so it must have been on all night which has drained the battery.

How the hell can the air con just switch on?

It still might be faulty or to smal for the car if it is not OEM batt,
I would recomend that you disconnect the batt and then charge it.
as for the air cond. wel there is a aux fan function that you can program to go on

Hi Dooby scoo
I had the same problem when i tried to fix my gps and the battery died.
But i did not know that the battery died, so when i tried to start the car the same thing happened as you show us in you film.
so i just charged the battery and the problem was solved !

Thanks for the replies.

I am just concerned that the air con came on unannounced.

Why would this happen?
How do you stop this happening?

Well,

I don't know how to stop the air con randomly coming on but the battery seems to be charging ok...

Right,

I have just taken the car off the charger after removing the air con fuse and first time it starts.

WTF now? I cant have the fuses out every time there is a problem can i?