tt wiring issue

[trkdrvr76]

Hi all,

I have a 2020 rd20se. The issue is I believe with tt lights. All lights work
Brake Turn and hazards. But when I turn on the headlights I have no turn brake or hazards. So there is no problem in daytime but night time is the problem. Any help would be appreciated.

thanks
Paul

[nvs4602]

Check the ground between truck and trailer. You can even use jumper cables to connect ground on trailer to truck frame to verify.

[mmartin_tdc]

I second the ground test. Sounds like it may be grounding itself via the running light line, instead of the ground wire.