rvgrandma, if you feel comfortable doing it, remove the switch and be sure the connections are not crusted over. Or, you may have someone look at it to check all the slide switches? There is an electric spray to help the connections:
How much you get involved with this process might depend on if you plan to keep it or sell it. If they work in and out, you may want to leave them to the next person if you are selling the MH.
If you are keeping it, getting them fixed may head off a potential issue when you are camping?
Keep asking your questions on here as many folks are very experienced and will gladly assist you!