Hi

 Just got a double din aftermarket radio for my mk2 fabia Monte Carlo, plugged it all in but there seems to be no power. Any help?

That's a big ask with so little information.

 

Did the original work okay? What's the actual unit you bought? Did it need a wiring loom or adapter? Was it new? Have you asked the seller? Any other details?

The original unit worked fine, the new unit is an xtrons which came with a loom. I haven't yet spoken to the manufacturer, will I need to change the fuse as the original is 15amp but the new is only 10

If the new unit is fused at 10A then do not replace this with a 15A. Fuses don't do anything except blow when there's too much current going through them for the rated value of the fuse. You can't make something work by fitting a bigger fuse, the problem lies elsewhere.

 

You'll need to check if there's actually power from the cars loom going to the correct terminals on the xtrons unit, but the loom should be set up to sort all that for you. I would be checking the wiring diagrams and use a multi meter to validate power at the correct terminal, but I'd also be asking the supplier.