Troubleshooting Turn Signal Function On Vehicle To Vehicle Tail Light Converter  

I have a 2000 Ford F350 and am towing a fifth wheel travel trailer. Want to have mid-trailer combination amber marker/turn signals on trailer. Purchased dual function incandescent turn signal/marker lights and your 118158 vehicle to vehicle adapter so could have turn signals on trailer function without coming on when the brakes are applied. The 118158 is mounted on the trailer and the white wire from the input side is connected to trailer frame/chassis ground. The yellow wire on the input side is connected to the wiring coming from the truck for the left turn signal. The yellow wire from the output side of the 118158 is connected to the signal wire on the dual function turn signal/marker light. However, the signal light comes on when the brakes are applied, just as if the 118158 were not installed. I doubled checked with the sales person who assured me the 118158 would work with this application. I have double checked my connections for ground and for proper connection and they are as instructed. Also, when I was testing the left side turn signal operation, the red wire I am aware the red wire is not used in this application, however I would think it should still illuminate did not illuminate. I have not connected the right hand side green wire yet since I assumed if the left was not working the right would not either. Can you please help? I apologize for the length of this note, however I wanted you to know all of what I had done. Thank you for any assistance as I am at my wits end.

asked by: Robert F