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Many different harness types are used to connect tow vehicles' power sources to the electrical wiring on trailers. The difference between a 6-pin system and a 7-pin is that the 7-pin has a connection for backup lights. What systems are required by law for your trailer depends on where you live. These state laws are listed in the resource section below. If the loss of the backup lights doesn't present a problem, making the 6-pin connection is easy with the right adapter.
Step 1
Determine if the vehicle's 6-pin connector is round or square.
Trailer wiring diagram 6 pin (round) 7 pin trailer wiring diagram with brakes; Trailer Wiring Reviews; Before you tow any trailer, you should make sure it has functional trailer lights. Because installation works related to electricity scary many vehicle owners away, they prefer the experts at trailer shops to have the job done for them instead. Check out 7 Wire Diagram for Trailer Plug for a quick reference on trailer wiring. 7-Way trailer connectors are found on most recreational vehicles and are used on a larger gooseneck, 5th wheel, boat and utility trailers. There are two types of 7-way connectors. One has flat pins, which are often referred to as blades. The other has round pins. The round pin style is very rare.
Step 2
Look at the trailer's 7-pin electrical harness and determine if the electrical connections are flat or round. Flat connections have wide slots for the vehicle's male connectors to slide into. Round connectors have circular holes for the same connection.
Step 3
Go to a hardware store and select an adapter that joins the two different types of wiring harnesses.
![Wiring Wiring](/uploads/1/2/5/8/125834890/596780935.jpg)
Step 4
Slide the 6-pin side of the adapter into the vehicle's harness by pushing the two together. Slide the 7-pin side of the adapter in the trailer's harness.
Test that the trailer's lights respond to the vehicle's systems as appropriate.
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