72YF3

Update, I finally got around to taking my truck in to the dealer to have this blinker/high beam thing addressed. Yep, replace the multi-switch. Of course, they don't have one. It will be in, in a week. another trip to the dealer. At least it's covered under warranty.

I'm having this same issue (high beams flash on when putting on the left blinker only) . Started last week. 2020 Silverado 1500 LTZ, 55,000 miles. The turn signal lever felt/acted different for a day or so, then the high beams started the flash but only while engaging the left turn signal. Guess it will go to the dealer.