Peterbilt headlights.

2013 389 Peterbilt

Is this a ground cause of it is I’ve tried to find them all and their all tight any grounds behind the dash I did look there but didn’t see anything high up.

the guy came in with no headlights just markers/clearances but when he hit a bump headlights come on but then hit another. It’ll go out again. With the key off the lights were staying on also, And while I’m diagnosing I turn flashers on and everything flashes. But headlights still don’t come on. further diagnosing again now the flashers aren’t working and lost dash switch power cuz with the key off I get no light power from switches on. Then I turn the key the lights come on, I turn switches off lights stay on, I turn key off lights go out, and I know on this truck lights still come on with not needing to turn the key. As any other usual truck would. And also that the plugin to the headlight assembly’s. I have power to all pins from 7-10V. Idk which one is ground but I’m sure atleast 2 or 3 should be!! And now I come back for morning shift I have headlight switch on key off the markers are all flashing even the headlights now with key off and a little relay under the hood clicking with a trailer stop light fuse flashing. But I turn key on it all stops

 

Thanks I did check battery’s and all was good not much for connections there. Also while I was searching Google. The headlights started to work mysteriously again! Who knows lol but I’m not stopping cuz it’ll likely happen again. I have the chassis harness unplugged right now it’s all clean in there. Maybe I’ll replace the fuses. The Gregg’s crap ain’t much better unfortunately lol