I have a 1990 Mercedes-benz 190E 2.6. When I turn on my headlights my turn signals act strange. My left turn signal does not have that ticking sound when the brake is applied. My right turn signal does not flash when the brake is applied. When the brake is not applied the signals work fine. When the headlights are not on at all the turn signals work fine, whether the brake is applied or not. HELP!!!!