It may just be out of adjustment, have someone stand behind you when you go to reverse, and watch your lights. see if the lights come on-and go off b4 you get into reverse. if so, then the switch just needs to be cleaned/adjusted. even if they don't come on at all, try the clean/adjustment first before replacing it, there's plenty of posts on here and on the web showing how to do it. Unless you've just got $$ to burn, then have somone replace it.