Replacing a Trailer Plug: Step-by-step Guide

Whether you use your trailer for landscaping, construction, travel, or your favorite hobbies, you rely on it to get the job done. Not only does a trailer need to be durable, but it also needs to function safely on the road.

But what do you do if you start experiencing trailer light wiring problems? Simple, you need to replace your trailer cord plug.

We understand that trailer wiring problems can be frustrating, but that's where we're here to help! Follow this easy step-by-step guide for replacing your trailer cord plug, and you'll be back on the road in no time.

Why Do I Need To Replace My Trailer Cord Plug?

Over time connections can fail due to metal fatigue or corrosion. If you have a brake controller for your trailer, you've probably seen a brake controller warning. Maybe your brake or signal lights aren't working. No matter the problem, your trailer cord plug always needs to be in tip-top shape.

Regardless if you have traditional electric drum brakes or high-performance hydraulic disc brakes, having functioning trailer brakes and lights is important for not only you, the driver but also other road users.

Tools You'll Need

Before you start your installation, you should have these tools on hand:

Wire Strippers
Cable Cutters
Phillips Head Screw Driver
Flat Head Screwdriver

Steps for Replacing Trailer Plug

Replacing a 7-pin trailer plug is not only inexpensive but also a relatively easy job. Anyone can comfortably perform this DIY installation in as quick as 30 minutes.

Here's how to do it:

Step 1: Cut open the plug and expose wires

With your new 7-pin trailer cord plug to the side and your old plug in hand, you're ready to begin the replacement process.

Start removing the old plug by cutting through the entire wire at the base of the plug with your cable cutters.

To expose the wires, gently slice open the outer rubber shielding with your wire cutters at about 0.5 to 1 inch. Be careful not to cut too deep and damage the inner wires.

Step 2: Remove the wire shielding

First, individually separate each wire so that you have some leverage to work with. Now take your wire strippers and strip each existing wire by a half inch. The length of the exposed end may differ depending on your new trailer cord plug.

Now that all wires are stripped, you want to twist the ends together to ensure the cable stranding does not separate. If you have to take a little bit more of the wire shielding off for more leverage, you can.

Step 3: Insert cord into the new plug and attach center wire

After you've stripped back all your wires, take your replacement plug and slide the cord with the exposed wires through the end of the plug housing.

Once you have your wires at the end of the plug housing, take your flat head screwdriver and gently loosen all the screws around your new plug assembly, just enough to make space for your wiring.

Attach the center wire to the middle terminal connector. Generally, these are yellow but always __refer to your trailer service manual __to be sure.

Step 4: Connect cord wires to center terminals

Once you've pulled your new plug through, with the center wire attached and all screws loosened, you're now ready to wire the rest of the wires into your new unit.

All seven colored wires belong to their respective plug terminals. Most of the time, the assembly head will have the color for each wire molded on it. To ensure you avoid wiring problems, refer to your trailer service manual and plug installation instructions.

With each wire in its corresponding terminal, go ahead and tighten the screws. Be sure not to torque the screws too much as you may bend the terminal clamps.

Step 5: Seal plug assembly

Although not required, it's always good practice to wrap all exposed wires with some electrical tape. This is optional and will not affect your plug whether you wrap the wires or not.

Now you're ready to finish off our plug installation. Pull your plug housing back up the cord into its original position over the terminal assembly. Align the slot in the cover with the groove in the plug to ensure all colored wires in the cord connect to the correct terminals inside.

Now reinforce it by tightening the two screws (one on the top and one on the bottom of the plug assembly) that you originally had unsecured at the beginning.

Step 6: Secure plug housing

To secure the plug housing, insert the crimp connector into the slot in the plug cover and tighten it in place.

_Voila! _You have yourself a new 7-pin trailer plug.

Step 7: Test your new plug

Plug your newly re-wired cord into the outlet and start testing your handy work. Check that all your lights work appropriately.

Conclusion

Now with your new trailer plug, you're ready to hit the road again! Safely and responsibly.

It's recommended that you should always do a quick test on your trailer wiring circuits each time you head out to ensure you don't experience faulty trailer wiring.