7'6" unimount on 2002 gmc 2500hd. I havent had one issue with this plow until now. Just today, I noticed my plow headlights were on. This was a couple hours after I parked it. So I unpluged the bumper plug. I messed with some other stuff in the yard for about 15 minutes. Before I went in, I wanted to see if the headlights would come back on. So I pluged the plow light/control harness back in and lights are off. Cool. Took my tools to the shop and came back, light are ON again... This has me stumped. I can see a bad relay and the lights now working...but what would make them stay on continuously?? What should I start checking? The truck lights function correctly with the plow lights unhooked. I multimetered the harness pug for voltage to see what pins are hot, but got nothing on any of the pins.. Im confused.