2020 Sierra AT4 6500 miles.
I'm on my forth service issue with a service brake assist message. Last week they replaced the master boost assembly and the message came back up over the weekend.
I read in this forum that has been an issue with GMC for a couple years.
Also, the high beams pop up here and there with oncoming traffic. That just started happening. The new one is tire pressure warnings even tho its all good.
Anyone else having electronic issues with their truck?
Larry