I bought a used 2015 Sierra about a year ago. I had absolutely no issues until I took the truck in for service which included a recall (a year later with no previous issues). About 2 weeks after service, I encountered the Theft Deterrent System light, power flickered, clock reset, and the vehicle wouldn't start. I pulled back the key, waited, and tried again. It finally started, but the dash light (vehicle with lock) remained on. The next time I turned it on, everything was working.
I took the truck back to the dealership. They verified my battery was working perfectly, but they found a random wire that they said was causing a short. After 2 hours waiting at the shop, they rerouted this wire and sent me on my way.
Today, it happened again. Same symptoms. Same outcome. I am getting irritated with something that seems to be so simple. I actually installed a FIXD device a few days ago. When this happened, I had the app scan for codes. No alerts! Nothing. I did it a couple more times, but still nothing. The app allows for submitting for unlisted codes, but it only allows for choosing from a limited list of dash lights which did not include this one.
