Occasionally the car's headlights don't automatically turn off after exiting and locking the car with the switch in the full on position - usually they shut off after a period of some seconds but on several (rare) occasions they have not and once we missed it and the 12vt. battery ran all the way down. This first occurred shortly after purchasing the car but didn't repeat for some time, making it difficult to reproduce on command while on warranty. It recurred recently when I was working on the car, opened the door when the car was powered off, turned off the headlights before closing the door and later turning them on with the car still off before closing and locking the door. No amount of locking the door by touching the external handle or pressing the remote would turn off the lights (and after several lock commands the car stopped enunciating the lock attempts). The lights remained on far longer than the usual shut down interval (minutes). One can open the door and turn them off manually, but one must go through the power on - power off sequence for the lights to again turn off automatically, as they usually do. I repeated the sequence of turning the lights off and back on while the car was powered off (for what it's worth the driver's door was open and I was standing outside the car) several times, always with the same result. I'm also concerned there might be other sequences that can cause this or that it might occur randomly. I haven't found this behavior addressed specifically in the manual, though there is a section stating the lights will go off after 20 minutes which I haven't had the patience to try - however our battery did run down once, which would require longer than 20 min. I won't walk away from a car until the headlights have gone off, but another driver in the family insists on keeping the switch in the on position and, despite witnessing the problem, regularly walks away from the car without giving it a second thought, trusting it won't fail for them - so this is a relationship issue.... Any thoughts?
I would start with the 12v. Its 5yrs old already and everything runs off of it when the car is off. IMHO
Checkin the 12vt battery mignt be a good place to start with many strange problems but that seems unlikely in this case. This first occurred when the car was nearly new and continued to occur after the original 12vt was replaced just a year ago. We've learned we can make the problem occur with a specific sequence involving powering off the car while the headlights are turned on followed by turning the lights off and back on again while the car remains unpowered - as described in the original text. I'm guessing it might be a software bug and wonder if affects anyone else.
