4 Way Flat Trailer Wiring. Plug this easy to use trailer light tester into the 4 flat connector of your tow vehicle and the leds light up to confirm the wiring connections. Wishbone style harness features a 4 pole flat trailer end connector.
It may transfer electricity better so the connector is suggested for higher level electric in the vehicle. Test your right left tail and brake light wiring all with one handy light tester. Quickly and easily install a 4 way and 7 way trailer connector on your vehicle with this custom harness.
You will still be able to use the trailer with the 4 way after installing the 4 to 5 way adapter 20036.
4 way flat molded connectors allow basic hookup for three lighting functions. 4 way flat wiring wiring diagrams thumbs trailer wiring diagram flat four by bismillah. Some manufacturers will use red black wires instead of brown green yellow. 4 way flat molded connectors allow basic hookup for three lighting functions.
