Step 1. Find out if that is the problem.

Step 2. If it is indeed bad, then look at where the damage is and sdecide on a course of repair. It is likely a multi-conductor, shielded cable and the best bet would be to get a replacement section at a junkyard or perhaps from the dealer or maybe an electronics shop. Any splicing is best done by soldering the individual wires together then heat shrink tubing for insulation around each wire then heat shrink around the whole cable for added protection. It also may be that the wiring can be repaired, maybe just separate the melted wires and re-insulate each one.