I have a 2011 SG with front and rear custom dynamic blinkers that I installed about a year ago. I just noticed one of the rear blinkers does not work. The running light works but the blinker and brake to not work on the rear left. Any help for an electrically challenged person would be appreciated.

 

Pull it out, and try a good different bulb, if they work with the different bulb, then your original bulb is probably faulty. If you still have issues after trying a different bulb it's time to start tracing to find the issue from the socket back.

 

Like he said, after that start under the rear fender for rubbed wires there.

Batman