Trailer Wiring Question

I purchased one of those Hoppy in line "T" trailer wiring harness. I hooked everything up and the trailer lights do not work any ideas??

It needs to have the electronic box which converts the seperate brake and turn signal circuits of the vehicle back to the older style combined brake/turn signal circuit of the trailer. Other than that, the most likely problem is bad grounds. Both the car and the trailer need the harness to be grounded. I think that is usually the white wires.

did you check the connector? just use some small wire and a regular 1156 bulb while somebody hits the turn signals, brakes, etc

if you get nothing from the trailer connector, disconnect your T-harness and check the body harness the same way