head light trouble

[slplow]

I am still having trouble with my head lights on my 05 gmc/ blizzard 810. I have narrowed it to my truck side harness but do not know what wire is making my head lights switch from plow to truck when you move the the harness ? I do not see any wires broken or crushed. Could it be the ground wire? I notice when I moved the harness that the plow moved. On the last storm my lights kept on switching when I was back dragging or making snow banks and also did it a few time driving down the road.

[The boys]

Check all the relays for corrosion and make sure they are tight.

[slplow]

She's all fixed. Little black wire broke in the the big connector. Had a hard time finding what wire it was as I could not see any damage wire and could get the light to act up moving one wire at a time. I could only get the lights to switch moving the whole harness after the connector. finally after pulling each wire separate from one another the black pulled out. To check that it was the bugger I grounded it to the plow frame and the lights when from plow to truck. I was hoping for a easy splice job but ended up replacing the harness. Another problem I had is that I had to drive an hour and a half to get a harness.:headwall

[Fastjohnny]

If I understand right, it was the truck side harness? If so you could ground that wire to battery ground. The little black wire just ties in with the large black ground wire at the plug. Keep it for a spare.