Seems a very trivial matter, but I can't work out which fuse the cigarette lighter is controlled by.
The manual doesn't mention it, and all other items seem to be working.
It could just be the cigarette lighter itself is knackered.
Do you mean you have a cigarette lighter that doesn't heat up or ther is no power from the aux power socket. If it's the first one then I'm pretty sure it's because it's not a lighter socket but an aux socket.
If it's there is no power from the socket for say a phone charger, then try Fuse 9 - a 30amp fuse in the BSI behind the glovebox door. Should be the 6th from the left