92 4 cyl. pickup.

headlight remains lit after vehicle is turned off. Stays off after poser is disconnected for a few minutes. Happens randomly, no pattern discerned. Occurs both when lights have been used and during daytime hours.

Nissan dealership has no answers. Thougnts? Anyone? Anyone?

Since the lights turn off when power is disconnected to some sort of a control module then it sounds like that module is the trouble.

I would look at the headlamp relay, assuming your 1992 (Nissan?) pickup has one, which I believe it does.