I have a 1995 Seville sts. When the headlights, or sentenial, is on..the passenger side turn lights and passenger rear brake light doesn't work. Sometimes will flash twice and then stop. The drivers side works okay and with the headlights off everything works fine. Bulbs look good....Stumped....would appreciate any help.

check the sockets. i bet you have a bad socket.

Thanks for the input....I didn't think about the sockets.. but they look okay....replaced the bulbs....all hazard lights work with the headlights on...it is just the passenger side turn lights and brake light that doesn't work with the headlights on....flashes fine with lights off and then turn the lights on and it flashes once and then stops. Do you think it could be the turn signal switch on the steering column?

try wiggling the bulbs while it is meesing up to see if they start to work....i be you have a bad socket