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Automatic Headlights

I have a 96 oldsmobile ciera sl and I just recently purchased the vehichle, I did alot of research on it before I got it and the one I got is in great shape, I was wondering though I never read anywhere where there were “automatic headlights” that come on when it is dark. Yet mine do it. Is this an aftermarket product? I can not find on any forums anywhere where anyone else had this. I turn my headlights on at night and it doesn’t change they are on at night whether I turn the switch on or just leave it off… Can anyone figure it out? I have a car that thinks on its own lol.

Does the owner’s manual have any information about this?

Do the tail lights and marker lights come on too, or just the headlights?

Is there a small bulb looking sensor located near the defroster outlet? This is where GM typicaly puts the “darkness” sensor. Cover it up and see if the lights come on,if the lights are on put a light on it for a few minutes and the lights should go out.

So I looked over the owner’s manual and there was nothing in there about automatic headlights I also looked for the sensor you speak of but the only thing resembling a sensor was a blue light located next to the headlight switch. I find this kind of odd… is my car alive haha.

Yes, there are aftermarket auto-headlight adapters made. They used to be pretty common to find in auto stores, I don’t know if that is still true. Many that I saw would also turn on the headlights when the wipers were turned on. It sounds like you probably have an aftermarket setup.

mcparadise asked if the tail lights and marker lights come on as well.

Are you sure those are headlights or are the DLRs (Daytime Running Lights)?

Daytime running lights would come on all the time, not just “that come on when it is dark.”

Not necessarily. GM is known to use the high beam bulbs as DRLs. When the lights are turned on at night via the switch the high beam bulbs revert to being controlled by the high beam switch.

That may be what Joseph is wondering. I’ve seen people lots of people driving around thinking their headlights were on when in fact only the DRLs were on.