Do the doors unlock with the physical door mounted buttons? If they dont then you will need to do a deep scan of the vehicle and check for any codes which will not show up on the dash, B,C,P, U. A good bi scan tool can send commands to your doors to see if the network is good. Even though you have a 19, Your vehicle Battery may be causing some issues and you get it checked out.. Good luck
Not sure what GM is doing with their OEM AGM batteries, but on my wife's 17 Nox the traditional lead acid battery from the factory was only good enough to insure getting past the B to B warranty. It lasted one month short of 4 years and probably only that long because I live in SC where the battery wasn't subjected to any cold weather stresses. The factory supplied AC-Delco was only 525 CCA, the replacement AC-Delco I installed was 650 CCA.Great to hear that what is was, it is a pity however a 19 with 36k will need a new AGM battery.
I believe you're right arcee, there seems to be enough anecdotal evidence to support the theory that the newer batteries don't last as long. I have my own theory as to why and anyone is free to shoot holes in it, but here goes. In order to meet competitive pressures, shortcuts in the lead recycling process by the battery manufacturers have resulted in contaminated lead alloys. Odyssey Batteries claims to use 99% pure lead in their AGM batteries with 3X the service life of the average battery, but they are very $pendy. As usual you get what you pay for I guess.Batteries aren't what they used to be. The battery in my 2015 Equinox lasted 4.5 years including a few months each year at or below freezing temps. Replaced it with a battery from Advance Auto Parts. I owned a 2006 Chevy Impala for 5 years and it still had the original battery when I traded it in. The Hyundai I regrettably traded the Impala for needed a new battery after only 3 years.
A new AGM H6 battery [Champion house brand] at Pep Boys is $210...and includes a 48-month free replacement warranty. That is probably the route I would take. If the vehicle needs another battery before the 48 months are up...get a free replacement!