I have a 2006 GTC convertible and the headlights come on by themselves... a few times a day... there doesn't seem to be any pattern to it. When it does happen, the lights stay on after the car is turned off and stay on, never turning off until you turn the switch for the lights to the on position and then back off. I have had the multi function switch replaced and that did not fix it.

Also, when the lights are on by themselves, the car is "not aware" the lights are on because you don't get the dinging warning you get when you actually turn the lights on and then turn the car off... so, something is activating the headlights...

any thoughts?

 

one other note: I can be riding down the road and the lights are off... then a few mins later, pull up behind someone at a light and see my headlights are now ON, even though they were just off a few mins ago and nothing has been changed... also, when the lights are on, the rear lights and the front parking lights are not on... just the headlights...

 

If I had to guess, and it's just a guess, I'd guess that your body computer has an issue. Nowadays it seems as if they feel that everything has to be run through some computer system or another whether it makes any real sense or not. Switches don't really control things, they just make suggestions to the computer as to what your current preference might be.

 

Same thing happened to me with a Ford Taurus. Problem was the daytime running light module. Exact same symtoms, crazy, as this could easily drain your battery.
Hope this helps.

 

I don't have a shop manual for this car so I haven't traced this circuit. My suspicion is that there is a headlight relay in the power distribution panel under the hood (or maybe in the driver's door fuse box) which is faulty. If there is a relay in this circuit, & I believe it likely, this would definitely cause the problems you are experiencing. If you have a shop manual trace the circuit & see if you can locate a relay. If not, you'll have to see if you can happen on to it through marking in the fuse box/PDC or in some cryptic web page somewhere.

Good Luck