I just picked up my new(to me) Trans Am, and I found out on the way home that the left turn signal doesn't blink, it just turns on and stays on. I checked to see if any of the lights were out, but they weren't. What could this be? The right one works just fine. And the gear indicator on my car doesn't work either. It's an automatic, and I can never tell if I'm in D or OD because it will slip by so easily. Thanks.

 

The flasher is probably broken. It's about a $2 item. Worth a try. The flasher is located in the Convenience center. It's above the drivers foot. I heard it's hard to get to though.

I'd just replace the shifter plate to fix the gear indicator problem.

 

If one side flashes and the other doesn't, it's likely there is a bulb out somewhere (could be something as silly as the side marker). Both left and right signals use the same flasher relay.
The best way to check is by turning on the hazzards and walking around the car, the hazzards will flash regardless of burnt out bulbs.

 

check the buld first, usually when one goes out that side just freezes.