Coolant Control Valve

[BadRobot62]

Just had the coolant control valve replaced on our 2021 Yukon Diesel . There is a TSB out for this according to the Dealership. What I got was a check engine light and a warning from OnStar. Has anyone else had this.

 

[OR VietVet]

I don't own one of the new rigs but I read all the threads about them and I have not seen anything about this problem. By the way, likely a typo, but it is TSB and not TBS.

Technical Service Bulletin.

Glad it is fixed.

 

[reddirtdigger]

Just had the coolant control valve replaced on our 2021 Yukon Diesel . There is a TSB out for this according to the Dealership. What I got was a check engine light and a warning from OnStar. Has anyone else had this.

Were your symptoms no rear heat? Did you get a Malfunction Indicator Light / error code or did you just notice it? I am having no codes, but no rear heat. I think my actuators are working, and feel no heat on coolant return line coming from rear hvac.