Left front indicator failure

[Alex_6.6]

Hey yall. I got. 2016 3500 with a Duramax. Having an odd issue that started the other night. My left blinker won’t work, when my headlights are on while I do it auto or manually the blinker indicator on my left mirror stays on (as I showed in the picture). The blinker will not work in the light but the 4 ways do. I checked all the grounds at the bottom of the radiator, under the driver door and under the passenger door. I also checked all the BCM fuses in the truck and they’re all good. Also, the first 3 blinks are normal then it goes into hyperflash. Any one have any ideas?

Edited 2 hours ago by Alex_6.6

[newdude]

Do the bulbs in the left headlamp and left tail light flash when you activate the turn signal?  

 

Any aftermarket headlights or tail lights?  

Edited 1 hour ago by newdude

[Alex_6.6]

40 minutes ago, newdude said:

Do the bulbs in the left headlamp and left tail light flash when you activate the turn signal?  

Yes. When the headlights are on in manual or automatic they don’t work at all when they are off they work but with hyper flash. Both front and backs the rears work at all times