I find myself with a similar problem ...
My 2005 Plus 4 has been outside under a cover for three months while the garage was rebuilt. It would normally sit inside with a battery conditioner attached. Much to my surprise the car started first time ... but absolutely refuses to start again. I've plugged in the battery conditioner and left the battery to charge up overnight, but still all I can get is a weak "chattering" noise.
Pouring with rain this morning, so avoiding lifting bonnet but would appreciate a pointer about what's next.
