1998 Cadillac Deville head lights

Aren't the daytime lights on the high beam bulbs(inner) burning at a lower intensity? Try manually turning the headlights on, check that all park and taillights work, and try the high beams. If the high beams come on, and the inner bulbs are the DRL's, check for power and ground by bridging a low beam bulb connector with a test light. If it lights, you have bulbs out.