35 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 42" Ground

Ask the Experts about this Optronics Wiring

• What is the Wire Gauge on 10 Inch Electric Trailer Brake Magnets
  The magnet wires on Electric Trailer Brake Assembly # A35W42B are 18 gauge. The wiring going to the brakes from a trailer connector is usually larger such as 10 gauge # 10-2-1.
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• How to Extend Short Ground Wire on 4-Pole Wishbone Harness
  Wishbone 4-pole harnesses like # A35W42B, # A20WB, # W002230 and # A10-4225VP usually do have a short ground wire because most trailer frames are steel and they conduct well enough that a ground wire attached near the tongue will provide sufficient ground even for lights mounted all the way at the back of the trailer. On the other hand if you have an aluminum frame trailer that does NOT conduct electricity nearly as well as a steel frame then you might need to extend that 2- or 3-foot...
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• Trailer Wiring Connector for Triton 8x10 Aluminum Snowmobile Trailer
  For your wiring, you will need to test your wire functions to know which one connects where. I recommend using a 12v battery and simply connecting the negative terminal to the trailer frame and then connecting the power to each wire at the connector individually to determine function. It is not uncommon to have two wires running to one function location for each side of the trailer so there aren't any jumper wires across the frame needed from side to side. I've attached an article...
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• Troubleshooting Trailer Brakes Where Only One Assembly Locks Up
  The brake assemblies all will receive the same amount of power from your brake controller so the issue is the brake assembly that is locking up. Most likely it's adjusted tighter than the others which is causing it to lock up sooner. That would be the first thing I'd check. The trailer wheels should be able to turn by hand if they are off the ground but you should be able to hear the brakes drag on the drum slightly. Check to see if the one that locks up is harder to turn and that would...
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• Do the Ground and Power Wires From First Brake Need to Go to the Same Wires on Second Brake
  Great question! For the second brake it does not matter which one is connected to your 12V power and which is connected to ground. Just like on the first brake that gets spliced into the main 7-way wiring, the wires on the second brake are interchangeable. One should be connected to power and the other to ground.
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• How To Rewire Small 4-Way and Large 7-Way Trailers
  It sounds like you are either trying to wire a new trailer or rewire an old trailer. If that is the case then I do have options for you but I do not have any reference to an "elicit axle/trailer". In order to wire/rewire your trailer we will first need to determine how many powered circuits it has. The majority of smaller trailers will only have three powered circuits which are for left side stop/turn lights, right side stop/turn lights, and running lights. If this is all you have then...
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• Gauge of Wiring in 35 Ft 4-Way Trailer Wiring Harness # A35W42B
  The gauge of the wiring in the 4-way kit part # A35W42B is 18 gauge.
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• How Many Wires are Typically Ran to Trailer that Only Uses Lighting Functions
  Typically you only need to run three/four wires for standard trailer lighting. One for running lights to each assembly and then two for each stop/turn light. Sometimes you have to run the ground wire to each assembly but typically they ground through the hardware and that's not needed. I attached a diagram that shows how trailers usually wire up. The style of connector usually installed on a trailer like yours is a 4-way flat like the part # A35W42B which comes with 42 inches of...
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• Recommended Trailer WIring for 4-Way Flat, 5-Way Flat, 6-Way Round, and 7-Way
  For a Trailer Wire Harness I recommend the following options: For a 4-way Trailer Harness use # A35W42B. This is a wishbone harness so it has wiring to each side of the trailer separately. Likewise for a 5-way wiring harness use # A40W5B. For a 6-way, I recommend using a junction box like # 38656 with Connector and Lead Wire # H20036 For a 7-way, I recommend # e99011. The remaining wires will use # 12-2-1 or # 12-1-1 sold by the foot. I've attached an article to assist.
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• What is Wire Gauge of Optronics 4-Way part # A35W42B
  All of the wires in the Optronics 4-way wiring harness part # A35W42B are 20 gauge.
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• How To Wire a 5th Wheel for Triple Towing a Trailer with Brakes
  It is possible to triple tow (1 tow vehicle + 2 trailers) when both trailer's have brakes but this would mean that the brake output wire that runs from the brake controller in the tow vehicle to both trailers would need to be at least a 6 gauge at the minimum so you don't have issues with voltage drop. Also, the number of braked axles cannot exceed what your brake controller is capable of handing which most are usually four. In order to obtain the needed length of 6 gauge or greater wire...
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• Troubleshooting a 4-Way Wishbone Trailer Connector Without Running Lights
  Traditionally, the brown wire is the running lights. On your trailer you have a 4-way wishbone connector, similar to our part # A35W42B. With a wishbone the running light circuit is ran on two wires one going to each side of the trailer. This usually makes wiring the trailer easier. Do you have running lights at the vehicle's connector? Use a circuit tester, like part # 40376, to test each function on the back of your tow vehicle. This will isolate whether the problem is with the...
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• Tracking Down Possible Poor Ground Connection on Travel Trailer
  What you're describing is the classic symptom of a poor ground connection somewhere in your trailer lighting system. When all the functions are being used, you're drawing maximum amperage through the system, which is when a ground problem will manifest itself. Trace the white ground wire back from the trailer connector. The wire will usually ground to the trailer frame somewhere on the trailer tongue. Make sure this connection is secure and not corroded. Each trailer lamp will also have...
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• Can 12 Volt Brake Controller Operate 6 Volt Brakes
  You must have a vintage Airstream or something with old Warner electric brakes. Technically you could adjust the output voltage on any brake controller down to 6 or fewer volts (by adjusting the gain or power output knob) and it will work with the 6 volt brakes that you have without having to add any additional parts or a separate voltage regulator. There isn't a brake controller that is set up to work directly with 6 volt brakes and using a 12 volt controller will not harm the...
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• Availability of Complete Replacement Trailer Wiring Harness for 1989 Wells Cargo Enclosed Trailer
  We do not offer complete OEM-style trailer wiring harnesses for specific trailers but we do carry all of the various connectors, plugs, sockets and other components required to re-wire a trailer from stem to stern. I have provided two links to our main pages for trailer connectors as well as two comprehensive articles on trailer wiring and troubleshooting.
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• How Does the 35 Foot Wishbone 4-Way Trailer Wiring Harness # A35W42B Function
  The way that the 35 foot Wishbone 4-Way Trailer Wiring Harness, # A35W42B, works is instead of having 1 taillight wire (brown) that you would need to splice into in order to run to both taillights, this harness has two wires (one attached to each stop/turn signal wire). The wires are attached to each other (except at the 4-Way connector) so you cannot mix them up. This would be good for your application since you will not have to splice wires that could end up being exposed to the water....
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• Wiring Brakes On Tandem Axle Trailer
  Typically trailer wiring is color coded. The brake circuit is usually a blue wire which travels to each brake magnet, where it is attached to one wire from each brake magnet. The other wire from each brake magnet will ground to the trailer frame. I have attached a drawing that shows how the wiring is typically run for brakes on a trailer. I have also attached a link to trailer wiring diagrams that may help.
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• Replacement Trailer Side 4-Way Flat Wishbone Trailer Connector
  It sounds like you need a replacement 4-Way wishbone trailer side connector like # A35W42B. It is a 4-Way harness but has 5 wires, 2 of which are for running lights. I have included a link to a video showing a typical wiring and light replacement for you. If you need to plug a 4-Way flat trailer side connector into a 5-Way flat on a vehicle, normally you will not need an adapter because a 4-Way can plug into a 5-Way most of the time. If you are actually looking for something else let...
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• Replacement 4 Way Wiring Harness for Yacht Club Snowmobile Trailer
  You're on the right track! If you're wanting to install a new 4 way connector on your snowmobile trailer you can use the 35-ft 4 way Trailer Wiring Harness # A35W42B. This is a wishbone style harness that comes with the tail light wiring already split up to allow you to more easily run the wires down the sides of the trailer to the lights. This wiring harness has 35-ft of wiring to accommodate even the longest trailers and can be trimmed down as needed to accommodate for shorter trailers....
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• Heavy Gauge Trailer 4-Way Wiring, 16 Gauge
  The longest 4-way harness we offer that has all 16 gauge wire is the Wesbar Harness part # W787274 which is 14 feet long. For one that is 30 feet long that has a 16 gauge ground wire and 18 gauge signal wires you would want the part # W002230.
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• What Wire Gauge is Used on the 35 ft. Wishbone 4-Way Trailer Wiring Harness, # A35W42B
  I went out to the warehouse and pulled a 35 ft. Wishbone 4-Way Trailer Wiring Harness, # A35W42B, and used a wire gauge tool to measure the wires. The copper wire itself is 20 gauge. If you measure the wire with the insulation on it then it is thicker but wire gauge corresponds to the strands not the insulation part.
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• 7-Way Trailer Wiring Setup Recommendation for a Tandem Axle Trailer
  A 4-way trailer wiring harness wouldn't carry a brake signal so it wouldn't matter how many axles you would have on a trailer that has a 4-way. A better option would be a 7-way as that style of harness does carry the brake signal. Starting with a trailer side 7-Way connector you can use # H20042 which is 3 feet long. It doesn't have to be long though because it is going to the junction box. Speaking of junction boxes you can use # 38656. I have included a picture showing how it...
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• How To Wire A 7-Way Trailer Connector With A Wishbone Trailer Wiring Harness
  The best way to wire a 7-way plug on your trailer that has a 4-way wishbone harness is to use a junction box like part # 38656 from Spectro. The wishbone harness has two separate running light brown that connect both sides of the trailer running lights without the need to run a jumper wire between the two sides of the trailer. The # 38656 junction box will give you a nice way to wire together the trailer's leads and the 7-way plug like Hopkins part # H20044. You would use the junction...
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• Wiring 3-Wire Lights to Boat Trailer with Wishbone 4-Way Harness
  It sounds like you are using a wishbone harness to re-wire your trailer. A wishbone connector has a brown/green wire for the running lights on the right side and a yellow/brown wire for the left side running lights. You will also have a yellow wire that is for the turn signal and brake lights on the left side, and a green wire that is for the right side turn signal and brake lights. The white wire, as you mentioned, is for ground. On your trailer lights, most likely the red wire is...
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• Recommended Wishbone Wiring Harness to Rewire Trailer with Surge Brakes
  Rewiring your trailer is something that you can absolutely do easily and there are harnesses called wishbone harnesses that don't require any wiring across the trailer frame. I recommend the 35 ft. Wishbone 4-Way Trailer Wiring Harness with 42" Ground Wire # A35W42B. I've attached a review video as well as an installation video to assist. I've also attached an article on wiring to assist with diagrams. If you have the electric reverse lockout on your trailer coupler, you may want the...
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• Troubleshooting Trailer Wiring with Brittle Ground Wire That Keeps Breaking
  If the wire is that fragile, I recommend replacing it now. If you can find a part of the wire to splice into then you can absolutely do that, but if it is too fragile then it won't provide a good ground and the other wires in that harness are likely made of the same material. If you can find a solid point of the wiring you can splice in # 16-1-1 with butt connector # 05731-5 and ring terminal # DW05737-1. I recommend the 35 Ft 4-Way Trailer Wiring Harness - Wishbone Style - 42" Ground...
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• How to Wire Second Axle of Trailer for Brakes
  Yes, you can jump the front axles brake output circuit to power the rear axle. Check out the picture I attached to see how most people do this.
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• How to Wire a Trailer so that Second Trailer Could Be Towed Behind It
  The correct part you would need would be the 4-Pole Wiring Harness part # 118603. You would need to use quick splices like part # SWC501746-1 to connect the wires of this harness to the correct wires of your travel trailer taillight wiring. The brown wires will run to the running light circuit, the green to the right stop/turn, the yellow to left stop/turn and the white to the ground circuit of the trailer. This will give you all of the taillight signals on a 4-way that you would...
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