[65truckowner]

I am almost done with my 65 c10. I was finishing up some stuff today on it. One of the headlights did not work on high beam so I thought I would change it with another headlight I had laying around. I did and then neither headlight would work on low or high. So I put the other one back in with the same result. The ground was a little loose so I changed the plug with a good one and still nothing. I then ran a ground wire from the battery to the headlight and with it just hanging by the harness both came on. I re installed the headlight and nothing but the passenger side works on high only. I have a new under the dash harness,dimmer switch, and headlight switch. Any ideas?