by MrFlibble » Tue Mar 21, 2017 11:44 am
You have a short circuit somewhere. First thing to do is to remove the fuse that powers that circuit. Replace it with a fuse that has already been blown, but with a (good) bulb wired across the fuse contacts. This will allow you to power up the circuit, but the bulb will limit the current flowing, preventing the wire from burning. Trace that wire through until you find a short.
Once you've found it and fixed the short, replace the burned wire. The insulation is no longer trustworthy, and you could get further shorts in future.
2012 Mk7 100 T350 LWB RWD medium roof