Battery issues 2020

[GrocreyGetter]

I have a draw somewhere, the original battery died when it got cold. Replaced it with a x2 h6 battery and it died in 2 days after install. Alternator was charging at 15+v and had to jump it every day. Took it out because it seemed like I bought a bad battery, batteries plus test it and load test it and it works perfectly fine with them. I purchased a autozone duralast h6 agm platinum and it made it further than the X2. Sat overnight at the dealer this morning when they went to look at it the battery was completely dead. I can not figure it out, neither can they. My Cobb tuner cord is pulling a 5 mili amp with the accessport unplugged. Which isn’t enough to completely kill a battery overnight. The alternator is fine according to them and so is the starter. Is there a common issue that I’m not able to find or??? Please help!

 

[Dale5403]

Did the BMS get reset? It should be done when installing a new battery.

 

[GrocreyGetter]

Did the BMS get reset? It should be done when installing a new battery.

Yes I did it with each battery. Battery light flashed every time.

 

[GrocreyGetter]

Did the BMS get reset? It should be done when installing a new battery.

so the dealership has found the throttle body is actuating while the car is off.