So tonight my cigarette lighter broke and won't charge my Sat nav which is bad.

Anyone know how easy they are to replace? or what could be wrong with the current one?

Fuse?

it is usually the fuse mate, if you got your owners handbook look in the back and find out what fuse it is. its worth checking this first. when you open the drivers door there is a plastic panel on the side of the dash, just pop it off with a screwdriver and the fuses are there an numbered

Guess I can pick a new one up from Halfrauds?

could be something else but would just check it first. yeah halfords should sell fuses

Yes but I'm sure in the fuse box there's a spare fuse or two which may be the right ampage ?

F42, 15A. HTH