My buddy in Phoenix melted his whole bumper last summer.

Feel your pain, I once nearly got kicked out of a cafe for arguing about the ending of Gone Girl.

Honestly, I've had that happen. A loose wire can rub against the frame or another part every time you hit a bump. Over a few hundred miles, the insulation wears right through and shorts out. It looks like it's been chewed because the rubbing is so focused in one spot. My fix was to wrap the section in split loom tubing and use a couple of zip ties to secure it away from anything it could touch.