2012 GMC rear blinkers aren't working

Yes, I have a I haul hitch on there but I put that on the day I got it in 2012.

Uhaul

Ok but the thing is those wires are more prone to failures as they are more exposed to the elements.. Combination switch is a possibility - however: Only *hands-on* testing will allow the culprit to be discovered.

Recommend testing commence at trailer wiring.

Just for the heck of it take a look at this: https://www.autogenius.info/gmc-acadia-2011-2012-fuse-box-diagram/ I think you really should use that lmk.

I checked the fuses first with the diagram in the manual.

*TEST* each fuse with signal lights on - using a test light..

Don’t overlook the fuses for towing that is shown in that diagram..

Good luck!