Round style 5 pin connectors also exist. Dont skimp on wire size for your brakes.

Curt 58671 Vehicle Side And Trailer Side 4 Pin Round Wiring Harness Connectors
4 way round trailer plug wiring diagram. You will need to use a circuit tester part 40376 and find out which pins presently transmit which functions. Unfortunately there is not an industry standard wiring configuration for the 4 way round trailer connector part pk11409. Trailer electrical connectors come in a variety of shapes and sizes. While the basic configuration is a 4 way flat connector that features one female and three male ends you may come across connectors with up to seven pins for additional functions that require wiring including electrically actuated brakes power source for a winch etc. In the trailer wiring diagram and connector application chart below use the first 5 pins. The basic purpose remains the same whether your truck and trailer is using a 4 way 5 way 6 way or 7 way connector.
By law trailer lighting must be connected into the tow vehicles wiring system to provide trailer running lights turn signals and brake lights. Trailer plug wiring escalade tahoe. My towing cable wires colors are green red brown and yellow can you show or explain the way to connect it to connector. One way to check for faulty wires is to use a circuit tester. Utility trailer 03 4 pin trailer wiring and diagram duration. Check with a test light or vom.
In this video we go over how easy and fast it is to convert a 4 flat harness to a 7 way. For a single axle 14 gage is good but for tandem axles use 12 gage. Lets see what types of connectors the trailer light wiring industry uses today. Round 1 14 diameter metal connector allows 1 or 2 additional wiring and lighting functions such as back up lights auxiliary 12v power or electric brakes. Installing your 4 pin trailer wiring system is easy if you follow the correct procedure. If your vehicle is not equipped with a working trailer wiring harness there are a number of different solutions to provide the perfect fit for your specific vehicle.
Etrailer 7 way trailer wiring upgrade kit installation. If it is not no amount of wiring will get the lights to work. That way the trailer brakes are ready if the tow vehicle has a 7 pin connector. Make sure that all cables are electrically conductive. 6 way systems round plug. The first thing you need to do is make sure that your connector works properly.
The black sometimes red 12v and blue electric brakes wire may need to be reversed to suit the trailer. Complete with a color coded trailer wiring diagram for each plug type this guide walks through various trailer wiring installation solution including custom wiring splice in wiring and replacement wiring. Wiring diagram recommendation for 4 way round trailer connector question. Does your vehicle have a 4 flat trailer wiring harness but you need to tow a trailer with a 7 way harness.