On Tuesday, my wife went to start our van (8 months old/10k miles) and it wouldn’t start. It was towed to the dealer same day. The dealer did a battery test (which takes 3 hours) and the primary was completely dead and the auxiliary was weak so they replaced both under warranty and luckily had them in stock. It was fortunately a 1 day inconvenience but I still have questions. I’m obviously trying to understand how an 8 month old battery could just die and the dealer tech said that it could be related to how we regularly disable the ESS. He said it’s “ok” to disable it the warmer temperatures, but in colder weather (we live in Midwest) to allow the ESS to operate in order for the auxiliary battery to properly pull a charge from the main. I was also told that with ESS, you should be sure to drive the car 20+ miles at least once a week in order to sufficiently charge the auxiliary battery. This part I don’t agree with. Why should we have to alter our driving habits for this to be done?? My wife is the primary driver and tends to do mostly shorter drives around town. I honestly would’ve preferred them to just tell me it was likely a bad factory battery..