Transit 320S 12V Charger not working and USB retro fit??

[WillsT]

The 12V cig lighter/ charger above the steering wheel has no power coming from it however the other 12v supplies in the van do. Is this likely to be a fuse or the actual unit itself, if so which fused would it be?

Also the unit has the USB port blanked over, what’s needed to get this to work and again where on the fuse board would I connect it up too?