Trailer Wiring Converter Diagram | Trailer Wiring Diagram Mar 23, 2019Visit the post for more. Related Post to Trailer Wiring Converter Diagram[PDF] Trailer Wiring Diagrams | etrailer - ActionOutboards because of a problem with the trailer wiring. Make sure to correct any trailer wiring problems before installing a new wiring harness. Converter Shorting Out When too many amps are drawn through the converter box, it can be shorted out. The possible causes are: Too many lights on the trailer.