Okay so here's the deal. My left turn signal will work when it wants to. If it stops working I will tap the headlight and it'll work again. I checked the fuses as well as the bulb. The filaments in the bulb look good. I was thinking the bulb socket could be bad. A friend suggested it was a short in the wire so I check and the wire has a plastic protective cover on it. Anyone have an idea what it could be? Thanks in advance.

 

Have you tried replacing the bulb?

 

You mean when you tap where the bulb is, it starts working? Like Ron said, the first thing to try there is a new bulb. I have had bulbs with loose connections inside, they look OK but don't always light up.