Trailer Brakes

I have a quick question for someone who is in the know, I seem to be in the dark. I have a tandem axle trailer with electric brakes. The brakes drag when I have the running light, turn signals on. I took everything apart last night and did some testing. I have continuity between ground and positive side of the trailer brakes. I also have continuity between ground and the running lights (but they work just fine when connected to the tow vehicle). what could be my problem?

thanks in advance,
Greg

I never thought that I would say this but it is good to be well grounded.

I redid all of the grounding on the trailer and it fixed all of my problems. By the way I am pulling it with a Ford Expedition.

thanks, GTRider