I have a 2018 XFs Sportbrake that I purchased on 12/7/2020. I now have an issue with the battery warning coming on after I leave the car unlocked in my garage for more than a day. The warning says to please start the car to bring the charge back to "normal" and if I lock it .... doesn't come back. The car was a demo & service loaner in the dealer's inventory, but was untitled and sold to me as "New" with 5,299 miles on it.

First, what does this indicate?
Should I worry about it?
Is it possible that the battery was harmed by the length of time the car was little used before my purchase?
Is it covered under my "new car warranty"?

Any comments would be a help to me. Thanks

 

My 2018 Sportbrake does the same.
I have had a dealer look at it several times they say nothing wrong, so I just make sure I keep it locked.

 

How far away are your keys from the car when it sits unlocked? Have your tried locking it and seeing if it persists?

Just a theory but you might be triggering something based on close proximity and the car is anticipating your entry as a result, causing things to power up and weakening the battery.

 

Anytime you have doubts about your battery you should first measure the SOC (State of Charge). If low check your alternator output across the battery terminals with the engine running and it should be around 13.5V +/-. Charge battery and see if it holds it. Sulfated/bad batteries won't. If you only do short runs you may need a battery tender.

 

thought id chime in on this as well. don't have a jag (yet-hoping wife gives into a sport brake). but i do have a mini clubman. I noticed when i was making short runs in my neighborhood when i would shut off the engine i'd get a notification for me to basically start the engine to put some more juice back into the battery. did some long trips and was still getting the message. I learned that what i was doing with just hitting the engine toggle once and then leaving, when what i was supposed to be doing was hit the toggle once for the engine and then a second time to turn off any electronics. did a couple of longer drives after i started that and the message went away. not sure if this is something that could be the culprit.

 

Not necessary in X260, once turns everything off. My wife's BMW takes two and it's a PITA.