Hi,

My left tail/brake lights are working just fine. As for my right one, when I turn my lights on, one of the two bulbs comes on. I switched the bulbs, and the same working one came on again. But when I hit the brake, neither one comes on. Is this a wiring harness issue? Fuse?

Thanks

 

It's most likely a problem in the socket. Pull it apart and look for corrosion and use a test light to see if the power is making it there.