Cadillac and headlights

I have a 2000 Cadillac Catera and recently the low beam lights are turning on when inginition is turned but then won’t turn off even after key has been removed from ingition. Lights are draining the battery. Something wrong with daytime running light sensor?

I don’t believe there is a “DLR sensor”. It sounds like you have light switch or ignition switch problem. Good Luck.