If something electrical in your car or RV stops working, check the fuse box. A blown 30 amp fuse looks like this:
A good one has complete middle circuit like this:
You get a replace online or at general stores. They simply plug in. If it blows again then something is overloaded or not working. The purpose of fuse is to power off a device that is overloaded to prevent damage or fire.
A RV fuse box looks like this photo:
A car fuse box looks like this:
You can remove and replace yourself. Having a handy tool is better, but can do with fingers.