NHTSA Complaint #11692524 — 2021 GMC SIERRA 1500

Vehicle showing signs of a failing coolant flow control valve and/orcoolant temperature sensor. - AC takes a long time to cool down - Engine fan will stay on after the vehicle is shut off - I often see the notice of “A/C Off Due To High Engine Temp” From what I can find, this issue I’m experiencing is a known point of failure in this vehicle make/model/year. On 10/10/2025, I took the vehicle to Fountain Buick GMC Service in Orlando, FL. The service manager recognized the symptoms immediately, and even knew right away that the part to fix it was on back order - further bolstering that it is an issue that GM is aware of and deals with regularly. Per the service manager, GM’s initial response was to issue a “pay to play” software update that is covered under the 3yr/36,000 warranty, but not the 5yr/100K. Out of warranty, this “solution” costs $499.99, and has a < 10% degree of success. If the update doesn’t fix the issue, then it would be covered. However, the need for the software update was not communicated to consumers. Regardless, since the issue is not yet severe enough to be recognized via code (despite symptoms, pictures, and video), GM will not take any action under warranty towards fixing it at this time. The vehicle’s 5yr/100K warranty expires on 10/15/2025. If the code throws on 10/16/2025, it will not be covered under warranty, but *may* be covered under dealer assistance. And regardless, the $499.99 charge will apply, independent of warranty coverage. More important than the money is the safety. The engine’s temperature is not being regulated, the symptoms I’m experiencing are terminal, and this issue will not be fixed on its own.