battery issue Battery drain ?? 2016 IS 350 F Sport

[SpenceUSM]

I am having a reoccurring problem but might possibly know what is causing it but not why?

Car sits for more than 72 hours battery is completely drained to the point that there are weird noises and clicks from under the hood for a very long time; absolutely nothing works.

Replace battery with Interstate - ditto happens again.  Take it to local Lexus dealer; car has <23 K miles.  They check it out and say nothing is wrong; battery gets charged on slow charger.  Drive car for 8 weeks.  Car is parked again for 72 hours and once again total dead battery.

I checked and my wife has left the lights on AUTO; I know this shouldn't be causing the problem but they were on AUTO the LAST time this happened 8 weeks ago. I purposely turn them to off but it's my wife's car and when I mentioned this she said she had turned the headlights to auto just days before, when it was last parked, because she likes how they cut on or off.

Car will be at dealer again Monday but I am interested in anyone's experience with this battery drain issue.

thanks

 

 

[dantappin]

Any chance you have a dashcam, phone charger or some sort of parasitic load?

I have a similar issue withy IS 250 but I know it's the dashcam.