4-Pole Trailer End Connector

See what our Experts say about this Draw-Tite Trailer Wiring

• 4 Pole Trailer Connector with Two Wires Connected to One Pin
  As for the white ground wire that you mention, this wire should be firmly attached to a clean metal surface on the trailer. As the lights are currently working properly, you are most likely picking up the ground connection through the trailer ball. This is a pretty unreliable connection, and can lead to intermittent light malfunctions or failures. Regarding the current connector on the trailer with the two wires running into one pin, some smaller trailers are wired this way. Instead of...
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• Troubleshooting Running Lights Not Working on a Trailer Towed by a 1985 Volkswagen Vanagon
  The problem could be with the trailer connector. If you used the 4-Pole Trailer End Connector, # 18004, that you have referenced, it may be causing problems. Your 1985 VW Vanagon requires the Taillight Converter Hardwire Kit with 4 Pole End, # 119178KIT. Your Vanagon has separate turn and stop lights, that is called a 3 wire system. Most trailers use a two wire system so a converter like the # 119178KIT is required to convert the 3 wire system down to a 2 wire system. I have included a...
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• Troubleshooting Trailer Right Signal and Left Brake Stops Working with Headlights On
  When the headlights being switched on cause trailer light problems this either means that you have too many lights on the trailer or you have a bad ground somewhere. If your trailer just started doing this and you haven't swapped out or added any lights then a bad ground is the place to start. Check the grounds both on your trailer and your tow vehicle and make sure that they are securely connected to a clean, bare-metal surface. Sometimes even some paint can cause issues so if you just...
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• Troubleshooting Trailer Brake Lights that Only Flash When Brakes are Applied
  Try improving the connection of the main ground wire of the trailer wiring harness. Make sure it is attached to a clean metal surface. Or you can run all of the trailer wires back to the main ground. This is actually the ideal solution. But you can also check the current grounds for the lights to make sure they are making a solid connection to a clean metal surface. What you described could be an insufficient ground scenario so finding a way to improve the grounds will hopefully fix the...
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• Trailer Running Lights Work But No Stop/Turn Lights After Installing New Trailer Wiring
  Thank you for detailing your troubleshooting efforts with the new wiring on your trailer. First, check the ground wires on both the harness and the trailer. Make sure both are tightly affixed to a clean bare metal spot on the vehicle and trailer frames. You can sand off paint and secure the wires to a new grounding point if needed. A weak ground can cause all sorts of weird behavior with lighting. Check all wiring for signs of cracks or worn spots in the insulation that could cause a...
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• Troubleshooting 4-Pole Trailer Wiring with No Stop/Turn Signals on Honda Pilot
  In both 4-pole and 7-way trailer wiring the brake and turn signals are carried on the same wires. On a 4-pole connector like the one # 18004 that you referenced the left turn and brake signals are carried on the yellow wire and the right turn and brake signals are on the green wire. On a 7-way vehicle socket, see the linked photo please, the stop/turn signals are carried on the pins at the 3- and 9-o-clock positions. There are several possible causes for the stop/turn lights on your trailer...
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• How to Splice in Replacement 4-Way Trailer End Connector
  To splice in a trailer end connector such as the 4-Pole Trailer End Connector # 18004 or Hopkins Endurance Easy-Pull Harness w/ 4-Pole Flat Connector - Trailer End # HM38134 you will need to match the connector to your wires by function. On these connectors, the brown wire is the tail lights, the green is right turn/brake light, the yellow is left turn/brake light and the white is ground and your connector will likely be the same. Since your damaged plug does not have these you can either...
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• Will 7-Way to 5-and 4-Way Trailer Adapter C35FR Fix Flashing Trailer Lights, 2010 Mercedes GL450
  If the trailer has LED lights and you are having issues with them not working then you would need to use adapter # C35FR. To plug in a 4-Way, you would just not use the last opening on the adapter. That would be for a 5-Way flat (it works with both 4-Way and 5-Way flat connectors). In the event that the 4-Way on the trailer is not conducive to this design because of a rubber or plastic covering, you may have to trim it or replace the 4-Way end with a compatible one like # 18004.
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• Troubleshooting Trailer Brake Lights Not Working With 2021 Ram ProMaster 2500
  To begin troubleshooting this problem I recommend checking the connections on your T-One Vehicle Wiring Harness # 118618. Often when one function is not working it is due to a set of connectors not seated together properly. Try disconnecting and reconnecting the harness to ensure the connectors are seated together properly. While you are checking the connection it might be a good idea to give the wires a quick inspection. Although it is a new wiring harness, it is possible a wire got...
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• Troubleshooting Turn Signal Not Working on Trailer After LED Taillight Installation
  Based on what you have said, something is off from the installation of the new LED taillights. When it comes to 4-way wiring like the 4-Pole Trailer End Connector # 18004, the right turn signal/stop and left turn signal/stop run on the same circuit. Since you indicated that the brake lights are working the turn signal should as well unless the wiring is off from your light installation. I would recommend double checking the wires to make sure they are correct. I would also make sure that...
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• How to Diagnose a Fuse That Keeps Blowing in a Dodge Grand Caravan Towing a Tent Camper
  With this being an intermittent problem, it is definitely going to be difficult to diagnose. I would have assumed there would have been an issue on the trailer side, specifically a ground issue. You may still want to check and make sure all your grounds have good solid connections, but I think it may be something else. After checking your grounds, I suggest rechecking the 4 Flat on your Grand Caravan. Using something like the Circuit Tester Kit # PTW2993, you will need to test the port...
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• Trailer Brake Lights and Turn Signals Work But Running Lights Do Not
  Yes it could still be a ground problem when one lighting function is not working on a trailer. The brake lights and turn signals are on the same circuits, one for each side of the trailer, and the running lights have their own circuit. Ground problems normally show up when there is more draw on a system such as when you have the running lights on and then use another function like a turn signal or brake light. Make sure that the vehicle side and trailer side connectors are clean and free...
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• Trailer Running Lights Not Working when Connected to a 2002 Chevy S-10
  You can determine if the issue is on your 2002 Chevy S-10 by checking its trailer connector with a circuit tester such as # PTW2993. Have someone sit in the truck and turn on the running lights while you test the pins on the connector. If you are not getting any power on the running light pin then that does indicate a problem on the truck side. If the trailer connector on the truck is factory installed then it could be a fuse. Use the truck owner's manual to find the fuse locations. Be...
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• What Circuits do the Wires of the Trailer Light part # RVST51 Run To
  The Trailer Light part # RVST51 that you referenced has three wires on it. A white wire for the ground circit, a black wire for the running lights, and a green wire for the stop/turn circuit. The wires you have on your trailer that also have brown on them are most likely running lights and would get run to the black wire of the light. I attached an install video plus a diagram that shows typical trailer wiring as well.
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• Troubleshooting Trailer Running Lights Blowing Fuse on 1994 Dodge Ram
  It is likely you have a short somewhere on that circuit which is causing the fuse to blow each time you try to use your lights, but you can start by taking a quick look at your connectors to ensure they aren't corroded or damaged in a way that may be causing the problem. Apart from that you need to trace the wiring on your running light circuit and look for any crimped, bent or otherwise damaged wires and fix them as needed. I have also attached a couple help articles on trailer wiring...
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• Wiring Harness for 16 Foot Load Rite Boat Trailer
  It sounds as if you're needing a wiring harness to set up your lights on a typical boat trailer. Boat trailers usually use what's called a wishbone harness, like part # A20WB. A wishbone harness uses two separate leads for the running lamp circuit, one runs down the driver's side with the left turn/brake lamp circuit, the other runs down the passenger side with the right turn/brake lamp circuit. This makes for an easier installation, as you won't need to run run the wire down one side,...
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• Trailer Lights Do Not Work With 2012 Nissan Frontier
  Since some of the lights on your trailer are not working with your 2012 Nissan Frontier, the first thing to do is take a look at your owner's manual to locate any trailer fuses or relays and ensure they are all there and in working order. If they are, in order to determine the specific problem you will need to purchase a circuit tester if you do not have one - the very handy Cordless Circuit Tester # PTW2979 is my recommendation due to how easy it is to use - and test the connector on your...
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• Running Light Fuse Keeps Blowing Even with Trailer Running Lights Disconnected
  You have a short circuit somewhere that is causing the fuse to blow. To determine where the short is start by disconnecting the trailer from the tow vehicle. Replace the fuse and then use a circuit tester such as # PTW2992 to test the vehicle side trailer connector while someone sits in the vehicle and turns on the running lights. If it shows power and the fuse does not blow then the issue is on the trailer. If it does blow the fuse then the issue is on the vehicle. Likely causes of...
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• All Trailer Taillight Functions Work Except Running Lights
  This could certainly be a grounding issue. When a circuit does not have a sufficient ground, it can cause many different issues. If possible, I recommend checking all of the grounds for your trailer taillights. You will want to make sure the ground has contact with a bare, clean, metal surface of the trailer frame. If there is any rust or corrosion at the light ground, try relocating the light grounds to a suitable location. Another possibility is that the wire for the running light circuit...
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• 6 way square to 4 way flat connection not working on 1997 Dutchman Pop-UP Tent Trailer
  As long as your vehicle is wired properly, Green right turn and stop, yellow left turn and stop, Brown running lights and White ground, then you will have to figure out how the trailer is wired. If the adapter you are talking about was purchased and not hard wired then it could be the 4-way flat to 6-way square adapter for a Jayco RV, and those adapters are wired differently than most other trailers with 6-way connectors and this could be why your lights are not functioning properly. You...
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• Troubleshooting Wiring Harness Failure for 2004 Chevrolet Coloroado
  Checking for shorts is a great first step in troubleshooting your lighting issues. As you mentioned, a regular wiring harness converter box has a max amperage of 2.1 amps per circuit for stop and turn lights, and a max amperage of 5 amps per circuit for the tail lights. The Tail Light Isolating Diodes # 48955 you mentioned have a max amperage of 3 amps. There are several other things to check that might be causing your problems. Checking these additional components will ensure that you...
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• Troubleshooting Trailer Clearance/Side Marker Lights Working On One Trailer But Not Another
  There are a few different things that can cause the trailer side marker and clearance lights on one trailer to work when hooked up to your tow vehicle, but a different trailers lights don't work. The easiest and first thing to check is that the trailer side connector does not have any corrosion or debris causing the connector to not make a good connection to your vehicle connector. If no corrosion or debris is found then you will want to double check that the main ground on the tongue...
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• Troubleshooting Green Wire on Trailer Pulled by 2003 Ford Expedition
  On a 4-Way flat trailer wiring harness, the green wire will go to the right turn signal. The white is the ground, brown is running lights, and the yellow is left turn signal. Take a look at the trailer wiring diagram that I included. This very well could be a ground problem. If so, correcting the bad ground or broken wire could solve the problem.
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• Parts Needed to Add a 5-Way Flat Trailer Connector on a Van
  If the van has a 4-Way flat trailer connector then the only functions carried by the connector are left turn/brake light, right turn/brake light, running lights, and ground. In order to get reverse, you will need to install Adapter 4 Pole to 5 Pole Trailer Wiring Adapter, # 20036. The extra blue wire pictured will attach to a reverse light wire behind one of the tail lights. Or, since you have said your van has a 7 wire loom, a reverse light circuit may be found there. Use a circuit tester...
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