How to Wire a Utility Trailer // Brake Lights

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When Steph was assembling the Harbor Freight Haul-Master utility trailer she was doing great UNTIL, the lighting would not work! Even with all the troubleshooting she tried, still, NOTHING.

She almost called it quits, but decided to confer with her friend, Stephen, who has the same trailer, to see if he could offer some advice.

Well....you'll see what happens.

Take a look at how Steph wired this trailer. She's never done anything like this before, but reading and watching YouTube videos on the process gave her the confidence to try.

I must say, I was very IMPRESSED with all the tools, techniques, and supplies she used. Even if wiring a trailer is NOT in your future, these techniques and supplies can be used in other wiring projects.

I would say, that you should just watch the video as my written "tutorial" is not going to be nearly as comprehensive and detailed as what Steph has put into the video. I'll try my best, though!

Materials/Tools:

• HAUL-MASTER 1195 Lb. Capacity 48 In. X 96 In. Heavy Duty Folding Trailer (Harbor Freight)
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• PITTSBURGH AUTOMOTIVE Foldable Metal Wheel Chocks, 2 Pc. (Harbor Freight)
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• HAUL-MASTER 1000 Lb. Swing-Back Bolt-On Trailer Jack (Harbor Freight)
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• HAUL-MASTER Trailer Jack Wheel Dock (Harbor Freight)
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• HAUL-MASTER 600 Lb. Trailer Dolly (Harbor Freight)
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• HAUL-MASTER Four-Way Trailer Light Tester (Harbor Freight)
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• HAUL-MASTER 1200 Lb. Capacity 30-1/4 In. X 72 In. Convertible Aluminum Loading Ramp (Harbor Freight)
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• STOREHOUSE Self-Drilling Screw Assortment, 200 Pc. (Harbor Freight)
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• CHICAGO ELECTRIC 1/4 In. X 14 Ft. Protective Wire Wrap (Harbor Freight)
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• STOREHOUSE Terminal And Connector Set, 150 Pc. (Harbor Freight)
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• Sopoby Solder Seal Heat (Amazon)
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• CE Smith Trailer 16867A Trailer Frame Wire Clips (Amazon)
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• Klein Tools 11063W Wire Cutter / Wire Stripper, Heavy Duty Wire Stripper Tool for 8-20 AWG Solid and 10-22 AWG Stranded Electrical Wire (Amazon)
• 
  
• Weller Helping Hands with Magnifier (Amazon)
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• Cable Zip Tie Mounts (Amazon)
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• 40 In. 300 Lb. Capacity Low-Profile Creeper, Blue (Harbor Freight)
• 
  
• Steel License Plate Durable Car Tag Holder Backing (Harbor Freight)
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Trailer wiring 101: this is the part that attaches to the car electrical harness although the part of the left is not needed so Steph removed it.

Get yourself a package of these Terminal and Connectors. Steph got hers at Harbor Freight. They made it easy to connect the wires to the frame for grounding.

Some of the tools Steph used in the wiring process. Needle nose pliers, knife, automatic wire stripper, wire cutter, and scissors.

Using the Klein wire stripper to strip the wire.

This is a quick slice connector. There are a few of them included with the hardware.

Screwing the grounding wire into the trailer frame.

Attaching a ring terminal to the now bare wire.

Once the wires are inserted, needle nose pliers are used to clamp it down. The top fold over to secure the connection.

Testing the lights after consulting with Stephen. They work!

One of the specialty products Steph tried out were these solder free connectors. (Sopoby Solder Seal Heat) All you need is a heat gun to connect two wire. There's a link above if you want to read more about this product.

This protective wire wrap keeps the wires neat and contained. This product is available also at Harbor Freight.

The grounding issue that caused the lights not to work initially had to do with the placement of this grounding wire. It was supposed to be on the back of the taillight bracket. It would not make a good connection in that position so the work-a-round was to drill a hole in the frame and attach the ground wire to it.

Steph also used these self-adhesive Zip Tie Mount With Cable Ties to manage all the wires.

More wire management.

One of the grounding points on the trailer. All have to be placed right in order for the trailer wiring to work.

There are a few of these wire management clips included with all the trailer assembly hardware.

This is the part that plugs into the wiring harness on the car.

It was a great sight to see this all lit up after dealing with the grounding issue causing the lights NOT to work. Perseverance pays off (as does a little help from a friend!)

I will never be wiring up a trailer, but this was so interesting to watch. I especially liked seeing all the speciality connectors and the various means of cable (wire) management. Those things can certainly translate into other areas of DIY.

Good job Steph, your Pappou would have been so proud of you! 


Please note: This is not a sponsored post. 

FYI: We are not professionals, and we don't claim to be. This is what we found worked for our project. Yours may need a little different approach. Safety first!

FYI: Affiliate links are being used on this page. Purchasing via these links help support MDP!

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