omgitsgela

Okay, I figured this out by accident earlier today. Apparently, if you press the Dome Override button four times in a row, a chime indicates, and the lights will toggle between always on and switch controlled. I've spent WEEKS trying to figure this out and search for the answer.

All the lights are on whenever the engine is running, regardless of the position of the lighting switch. Headlights and marker lamps.

There is a sensor on the dashboard, but it doesn't appear broken or covered or anything. Not sure?

I inherited my 2002 GMC Sierra 2500 HD Duramax from my father when he passed away this year. It's such a great truck, and I love it. One thing I'm trying to figure out though... the headlights and daytime running lights are always on whenever the truck is running. The switch on the console is in the off position, and all the lights are still on. Doesn't matter what time of day. What's interesting is if I leave the headlight switch in the on position, and then turn off the truck, then the light controls work, and I get warning dings about the lights being left on. But whenever the truck is running, those lights just come on whether I want them to or not. How can I get the lights to stop running constantly, and instead use the switch? What do you folks think is happening here? Thanks!