My 2017 TLX with 30K would not start this morning. Iam in FL, so not that cold...
Dashboard was flickering and looked like that starter was spining but did not engage. Light were fine.
What to do first to diagnose?

 

The battery would be a good place to start

 

Battery...did not drive it for 3 days...dead.

 

that would do it! battery tender if you can plug it in will extend the life of your battery enormously. Also, if your battery is >5 years old, it's about time to replace it anyway.