I have a 2003 Saturn Ion - the right tail light is continually going out. I have replaced the bulb many times over the last several years. The brake light and turn signal work fine on that side. When I hit the cover of the light the tail light will come on sometimes but it will usually go out again while I am driving. It is not the bulb because I have changed it many times and the brake and turn signal work fine - Is this something to do with the wiring or electrical for the tail light? What causing this problem? And how much could I expect a repair of this problem to cost?