1979 mercedes turn signal problem

I have 1979 mercedes 300sd the turn signals work fine when the head lights arent on but when the head lights are on the right turn indicator on the dash stays on and the right turn signal dont work and the left turn signal works ,but the left turn signal running light doesnt work ?? Any ideas what might be wrong and how to fix it. It has me purplexed. :screwy:

that leads me to believe either the hazard relay or the turn signal switch is going on you.

that leads me to believe either the hazard relay or the turn signal switch is going on you.
Thx Hef I will explore those 2 posibilities Thx :naughty:

That might mean that a turn signal light blub

on second thought, check the ground just behind that right headlamp assembly.