Trailer Lights

Need Help. I hooked up my trailer lights last night and the turn signals and brakes work but running lights do not. I tried several variations but that only led to more trouble. And I did match them color accordingly the first time. Does anyone have any solutions? Thanks!

:WELCOME:

You have a bad ground.It's either the wiring harness ground on the trailer or the ball isn't grounding to the hitch or trailer tongue.Also check all your connections and splices.I use dielectric grease every where I have a connector or bulb socket.It can be bought for a couple dollars at any auto parts store.I check everything and reapply in spring.

what type of vehicle is the trailer hooked to? My 03 Ford ranger had a "tow / haul" fuse that was blown. I had brake and turn signals but no running ligts as you described. check to make sure your vehicle doesnt have a similar fuse.

that was with all new trailer wiring and a factory wiring harness on the truck.

Its a Ford 2004 F150. Much appreciated thank you! I will have to check these things tomorrow!

ALL newer trucks have separate fuses for trailer wiring . Also, I reiterate AGAIN , do not rely upon your hitch to make your ground!

I've been working on RV's and wiring trucks for a living for the last 20+ years , take my word for it . number one cause of trailer light issues is relying upon your ball to trailer frame for ground, but , sounds to me like you have a blown fuse look at your owners manual and then get into the right side kick panel for your fuse box.