Turn signal problem
 

On my 1966 Mustang convertible which I have owned for 45 years, I am having a problem with my turn signals. When I turn the lever in the car for a right turn both my left AND right brake lights flash. In the front of the car only the right signal flashes as its supposed to and when I turn the lever for a left turn only the left side signals in both the front and rear flash as they are supposed to. I bought a new flasher that goes under the dash but that did not help my problem. Would appreciate any help or advice any of you can give me to solve this problem.

sounds like a ground issue on the RR- clean all the connections and make sure all the correct bulbs are in use.

Here is the way the turn signals work. Your problem is probably in the emergency flasher switch.

Thanks guys!! My problem is now solved. I took all the wiring loose from both taillights, checked everything, put everything back together and now they work fine. I did notice that the ground wire on the right rear brake light was a little loose when I was taking it off. I made sure everything was good and tight and now they work like they are supposed to. Thanks again.!!!

yup I have the same issue. Also, remember that the connections on the lights do better if you use dielectric grease. it makes a big difference