I have a 2011 Buick LaCrosse. I was putting in an oem nav/radio. Everything was working fine....now the front turn signals don’t work. Any thoughts on where to start? Yes I changed the bulbs first just to be sure that wasn’t the issue.

 

Did you happen to be working around the fuse panel? Did you check the fuses?

 

I was working around the fuse panel inside. In fact I had a fuse go out because I was putting a switched power connection on a power outlet for the backup camera. I replaced that fuse. Through this process I have checked every fuse in the 3 main places (under hood, instrument panel, and trunk. The weird thing it is just these two front blinkers, nothing else. Normally that would point to a bcm but I didn’t mess with the bcm sat all.

 

Have you checked the wires coming out of the steering column? The signal comes from those wires to the BCM.

 

 

 

This may or may not be the problem.
First are you sure what is coming on with the headlights are the signal lamps and not the parking lamps?
Something you could check and that is the ground connection for the front lights. There could be a path for the heavier drain lamps to work, but insufficient for 1 lamp.
It's far out but needs to be confirmed.
Did you consider disconnecting the nav system and see if that might help?