Hopkins Wiring Harness with 4-Pole Flat Trailer Connector - Trailer End - 4' Long

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• Determining Function of Non-Standard Wire Colors on Trailer to Install 4-Way Connector
  The best way to connect the 4-Way to your trailer wiring is going to be to test each of those wires by applying 12V power to them. By doing this you will be able to see what each wire activates on the trailer to verify their function. Going by wire color alone, as you are seeing, isn't always a good idea because trailer manufacturers or previous owners have a tendency to use non-standard wire colors. Once you determine their functions the trailer wire for left turn/brake light will go...
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• Can Trailer with Brown Yellow and Brown Green Wires Run to Standard 4-Way
  Yes you would be able to use your current trailer wiring configuration with a standard 4-way that only has 4 wires like the # HM38138 that you referenced. Basically the yellow brown and the green brown wire would wire directly to the single brown wire of the 4-way and the other colors would match and you'd be set. What you have now is a wish bone setup that just has a separate wire for the running light circuit for each side of the trailer. We have 4-ways that are setup for this with the...
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• Will Adding 4-Way Wiring To a 2013 Cadillac SRX Risk Damage To The Vehicle?
  On your 2013 Cadillac SRX Luxury you want to use a wiring harness with a powered controlled module like the Curt # C59236. This module uses power from the vehicle battery to operate the lights on a trailer and reduces strain put on the factory wiring. By using a basic 4-Way # HM38138 you put all the additional power load for the trailer on the factory tail light wiring. Since manufactures have switched to using the thinnest wire power to save money this will likely overload the wiring and...
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• Converting A 5 Wire 4 Way Trailer Connector To Vehicle 4 Way Flat
  It sounds like you have a separated wiring setup with 5 wires - yellow, yellow brown, green, green brown, white. Typically, yellow is left turn / stop, green is right turn / stop, yellow brown is left running light, green brown is right running light, white is ground. You convert this to a standard 4 way by wiring the 5 wires to 4 flat harness # HM38138. This allows you to wire up all of your trailer wires color for color and then simply plug it into the vehicle's 4 way connector. The...
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• Recommended Plug to add Lights to Trailer Tailgate
  In order to add lights on your trailer's tailgate that will allow you to remove it, you can use 2 Wire Loop # 9651P. What you would want to do is cut it in half and use one side for your tailgate and one side for your trailer. I've added a link to a video review for you to take a look at as well.
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• 4-Way Trailer Wiring Recommendation that Uses all 16 Gauge Wires
  For a 4-way that has all 16 gauge wire you would want the Wesbar 4-Pole Flat Connector # W787264. The part # HM38138 uses 18 gauge for all wires but the white that uses 16 gauge.
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• What Gauge Wire does 4-Way Trailer Wiring Use
  Typically 4-way wiring consists of 18 and 16 gauge wires. For a 4-way that has all 16 gauge wire you would want the Wesbar 4-Pole Flat Connector # W787264. The part # HM38138 uses 18 gauge for all wires but the white that uses 16 gauge.
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• Can You Use The 3rd Brake Light Logic Module With A 4-Pole
  For your 2021 Chevrolet Silverado you will have to splice into the factory wiring to use the 3rd Brake Light Logic Module # PP20-702 to connect the left and right turn signals, along with the green wire. You can also combine this harness # PP20-702 with a 4 pole harness like the Hopkins Wiring Harness with 4-Pole Flat Trailer Connector # HM38138.
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• How To Wire License Plate Light/Bracket With 3 Wire Connection
  Most Trailer License Plate Lights with a Bracket like the Optronics # LPL55CB you found are only going to have 2 wires a power and ground for the light. It looks like yours has either an additional light for either a reverse light or brake light. While I cannot tell who manufactured your light you are most likely going to have to test the light with a 12 volt battery to determine which wires are power and for which function and which is the ground. Typically white or black are the most...
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• Replacing 4-Way Flat Connector With No White Ground Wire Causing Lights To Turn Off
  You are correct that you need a ground wire for your 4-way flat connector. When you are hitting bumps the coupler for the ball has a small amount of play inside which is causing your lights to turn off and on. The Hopkins Wiring Harness # HM38138 will give you a short 4' lead which you can splice into your trailer wiring and run the white wire to a good ground location on the trailer. This will ensure a good solid ground connection for the wiring on the trailer. The Heat Shrink Butt Connectors...
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• Parts Needed To Transfer Lighting Signals While Triple Towing An RV And Boat Trailer
  To triple tow you wouldn't be running both connectors to your Ram. You would connect the RV's 7-pole to your Ram and then connect the boat trailer to a connector on the RV. Since you just need lights for the boat trailer you'll just need a 4-pole connector # HM38138, some heat shrink butt connectors # DW05744-10, and some additional wire for length. You'll splice in the 4-pole connector to the lights on the rear of your RV to transfer your lighting signals from the RV to the boat trailer....
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• Can 4-Pole Wiring Be Submerged Underwater
  4-pole wiring like the Hopkins Wiring Harness with 4-Pole Flat Trailer Connector # HM38138 can technically be submerged underwater but you would want to ensure that the connections are all waterproofed with heat-shrink butt connectors, like # DW05744-10, for the bare wires and some Dielectric Grease # 11755 on the 4-Pole connectors.
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• How to Re-Wire Trailer with 4-Pole Trailer Harness
  A 4-pole trailer wiring harness has three circuits plus a ground, the ground being carried on the white wire. You will just need to test the functions on each trailer wire to confirm how to connect them to a 4-pole pigtail like # HM38138. A junction box # 38656 and ring terminals like # 44-5310A will make it easier to get solid reliable connections. You will want to ground a battery negative terminal to the frame and apply 12V power from the positive terminal to each trailer circuit, one...
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• Troubleshooting Malfunctioning Trailer Lights
  This will depend on the year, make, and model of your truck, but there is typically a number of fuses for towing a trailer. You will want to check your owner's manual for the specific fuse locations for these functions. If the fuses all look good, however, it may be something else. Using a tester, like the # PTW2993, engage the right blinker and check the output on the 3 o'clock position of a 7 Way plug, or the green wire port on a 4 Flat plug. These will both handle the passenger (right)...
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• Adapter Recommendation for 6-Way on Trailer to 4-Way on Vehicle
  For a 6-way to way adapter we do have the part # A10-6034VP. With this your trailer's 6-way would plug into it and then the 4-way of the adapter would plug into the vehicle. Best solution will be to replace the 6-way on your trailer with a 4-way to match your vehicle as that will eliminate the need for an adapter. For that the part # HM38138 would be your best bet.
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• Troubleshooting Turn Light Fuse Blowing With Cargo Trailer
  If you add additional wire you're still going to be getting under the trailer to run it. I would go ahead and look under the trailer to check for a short in the wiring. Many times this can be found near the lights where the wire connects. It would also be a good idea to check out your connector. Make sure it is free from any debris and corrosion. If you don't find anything, instead of running a separate 4-way I would run new wire from the lights to your 7-way connector. It would also be...
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• Do 4-Way Connectors Have a Power Wire
  Trailer and vehicle 4-way connectors like you'll find with the 4-Way Flat Trailer Wiring Kit - Vehicle and Trailer Ends # HM48205 do not actually have a hot - or power - wire. As you can see by the cut out I added of the linked help article on trailer wiring (which I highly recommend checking out), a 4-way will activate running lights, brake lights and turn signals. I have added a link to our entire selection of trailer end 4-way connectors for you to take a look at.
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• Tracker Boat Trailer Wires With 7 Wires Connecting Into A 4 Pin Plug
  It could be possible that your 2012 Boat trailer is wired with a wishbone style harness. Similar to Item # A25W2GWB. This type of harness just allows the installer to run each side separate rather than splicing and running extra wires across the bottom of the trailer. Your best bet may be to test each wire function before cutting. You cannot get trailer brakes from a 4 pin connector which is why I am leaning more toward it being a wishbone. Once you determine the proper functions all you...
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• Does the Blue Ox Tail Light Wiring Kit with Block Diode # BX8811 Come With a 4-Way Connector
  The Blue Ox Tail Light Wiring Kit with Block Diode # BX8811 that you referenced does not come with a 4-Way connector as you stated. To add a 4-Way connector you can simply use the Hopkins Wiring Harness with 4-Pole Flat Trailer Connector # HM38138 and connect it to your current wiring using Butt Connectors # DW05744-5. For a look that is a little more clean and will provide you with a 7-Way to connect to your RV you can use the Hopkins Nite-Glow Tow Bar Extension Cord w/ Socket - Coiled...
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• Converting Euro 7-way To Standard 4-Way Flat Trailer Connection
  I am not familiar with the bike rack with lighting, however, you can rewire the 7 pin euro by function to the 4-way flat. I recommend using the Hopkins Wiring Harness with 4-Pole Flat Trailer Connector - Trailer End - 4' Long # HM38138 along with quick splices like # SWC501925-1 or butt connectors like # DW05744-5. The 4-way functions are: White=ground wire Yellow=left turn/brake light Green=right turn/brake light Brown=tail lights I've attached a photo of the Euro functions for you.
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• Troubleshooting Trailer Wiring After Installing Lights And Wiring
  There could be a couple of reasons why the lights are not working now. You said you replaced some lights and wiring. I recommend checking all of the connections to make sure everything is secure and wired properly. You can use a circuit tester like part # PTW2993 to make sure all of the lights and wires are receiving current as designed. If everything checks out the problem is probably the ground connections. Check the inside of the trailer connector for corrosion. If you find any green...
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• Can You Connect the Thinline LED Trailer Tail Light Red Wire to both Green and Yellow Wire
  I believe what my friend Rob was referring to when he said to connect the red wire from your Thinline LED Trailer Tail Light # STL59RB to the yellow and green wires is to connect it to the yellow and green wires of the Hopkins Wiring Harness with 4-Pole Flat Trailer Connector # HM38138. From there you can plug the Hopkins connector into your vehicle wiring harness for power if you are using this on a cargo carrier or other hitch mounted accessory. This process will not harm your vehicle...
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• Availability of Adapter to Go from 4-Pole Round on Trailer to 4-Pole Flat on Vehicle
  I do have a couple options for you, but there isn't an adapter to go from a male (trailer end) 4-pole round to a female (vehicle) 4-pole flat or even a 7-way. So, you could either make your own adapter using part # PK11410 and # HM38138, if you do not want to modify the harness on your magnetic trailer lights, or you could simply replace the 4-pin round connector on them with part # HMC20031, which is going to be the most cost effective.
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• Replacement Wiring on Bully Lighted Hitch Step
  To replace your wiring on your Bully hitch step # CR-600LED I recommend the Hopkins Wiring Harness with 4-Pole Flat Trailer Connector # HM38138 along with heat shrink connectors # DW05743-5. For added protection you can add a wire loom like # 7509-1 sold by the foot. The wires of this harness have the following functions for you to match up to the wires in the step. White: ground wire Yellow: left turn/brake light Green: right turn/brake light Brown: tail lights
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