What may be the source of this issue?
The right turn signal display and turn lights work when the headlights are off. With the lights on, the right display light is on constantly. Turn the right blinker on and display blinks slowly, the turn light on the fender doesn't blink and the one at the bumper does. I replaced the headlight switch per mechanics recommendation but it didn't cure the problem.
Sound,s like it may be a bad socket,that the bulb go,s into,or wiring at it.All so make sure you have the right bulb.
Grounds also play a big role in this system, make sure they are good.
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