7-Way Round RV Style Trailer Connector - Trailer Side

Ask the Experts about this Optronics Wiring

• Installing 12V Power On Ford F-150 7-Way Trailer Connector
  You do not need to connect the 12V power connection on your F-150 7-way. That power is only required if you want to charge a trailer battery while towing or if you are using an electric device on your trailer like a powered sway control or wireless brake controller. It is likely that a fuse or relay needs replaced for the factory function if it was recently interrupted. I recommend checking your owner's manual for fuses and relays associated with this function. If you want to add that...
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• Going From Trailer Side 4-Way to 7-Way
  Though that 7-way isn't a part we offer so I can't confirm it's viability, what you will need to do is just cut off your 4-way and attach its wires to the 7-way. For trailer side 7-way connectors we offer, such as # A7WCB, if you are looking at it from the front, the pin in the 1 o'clock position is tail/running lights, 3 o'clock is left turn/stop, 5 o'clock is ground, and 9 o'clock is right turn/stop. The only way to confirm what the function of your 4-way are is to use a separate 12...
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• How to Wire up the Optronics Trailer 7-Way A7WCB
  It is hard to say exactly how much of the black wire insulation was cut off of the 7-Way Round RV Style Trailer Connector # A7WCB, but after watching the video and having done this myself before, it looks like Rick cut off about 2 inches of the black portion and then about 3/8 of an inch of insulation per wire. There is an industry standard for how 7-ways should be wired. If you check out the picture I attached you will see how they are typically wired. By function is how the connector...
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• 7-Way Plug Recommendation for Replacing 4-Way of Hitch Light Fixture
  What you described is a very good idea. You could just cut off the 4-way of the light and then wire it to the part # A7WCB and you'd be good to go.
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• Replacement 7-Way Plug and Cable for Hayes Sway Master Electronic Sway Control System
  A replacement 7-way plug and cable for the Hayes Sway Master Electronic Sway Control System is not offered. My contact at Hayes confirmed that the 7-way cable is hard-wired inside the control box and that no replacement part is offered. If the cable is still good and you need only the 7-way plug we do offer parts that will work for you. You can use Optronics 7-Way Round RV Style Trailer Connector # A7WCB or the Mighty Cord part # A10-7081VP.
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• 7-Way Trailer Socket to Mate with Plug A7WCB
  Part # A7WCB uses a connector format known as an RV-style 7-way blade. Although the plug itself is round the actual electrical contacts are flat or blade style. This male plug mates with a female socket such as # 37185 or # 30717. I am not familiar with the DTS brand but I presume it is the maker of the connector you have. My contact at Blue Ox confirmed that the threaded rods on the crossbar can be bent to fit a wide range of 6-way and 7-way trailer socket mounting hole spacing. I...
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• Does 12V Pin on 7-way Trailer Connector Always Have Power
  It sounds like you're asking about the 12V circuit on the 7-way trailer connector on the rear of your 2003 Chevrolet Trailblazer. Some vehicles will always have power and some others will not. We don't have this specific information for your vehicle, but to determine if your 12V always has power you can test the pin in the 1 O'clock position on your 7-way. The other pins will have power when the corresponding light is used or the brake pedal is pressed.
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• Wire and Function In A 7-Way Connector To Allow Brakes To Release When Backing Up A Boat Trailer
  The fifth wire that allows you to back up a boat trailer is the reverse function. Sending signal from the reverse function will allow the solenoid to disengage the surge brake function electrically. The reverse function is found in the center of the 7-way connector. I've attached a diagram to help.
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• Brake Controller Has Power But Trailer Brakes Do Not Work
  There are some tests you can do to determine where the problem is: brake controller, truck, or trailer. First, in the truck cab you will need to sever the blue wire several inches from the back of the controller. Then use a circuit tester such as # 40376 to test the end of the blue wire coming out of the controller. It should only have power when you apply the manual override or brake pedal. If it shows power at idle then there is something wrong with the controller and it will need to...
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• How to Wire a Replacement 7-Way for a Gooseneck Trailer
  7-Way connectors like the # A7WCB that you referenced should be wired by function and not color. Since trailer manufacturers can sometimes use non-standard color wires for the taillight functions of their trailer it is best just to determine the function of each wire from your trailer's wiring and then wire it by function to the 7-way you end up getting. What you can do to determine the function of each wire is use a 12 volt battery like a car battery and run a jumper wire from the positive...
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• Trailer Wiring Diagram for a 7-Way Trailer Side Connector
  The problem that you are going to run into no matter what 7-Way you want to put on your trailer is that the color of the wires used is not standardized. Trailer manufacturers or people who rewire their trailers at any point can use any color they have laying around. You have to go by function, and then follow our wiring FAQ diagrams which I have linked for you. The colors that we mention are the most used but are by no means definitive. If your old 7-Way is still attached you can just...
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• Recommended 7-Way Trailer Connector for Both Trailer and Tow Vehicle
  It looks like you found the trailer-side 7-way, part # A7WCB. If you need the wiring and connectors as well use part # ET7WK instead. The installation will be much easier. In order for me to recommend the parts you need to add a 7-way connector to your tow vehicle I'll need to know the year, make, and model of it. Also, is there a 4-way on the vehicle now or is there no trailer wiring at all? If you already have a 4-way connector you can use our # ETBC7 kit to convert it to a 7-way....
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• Connecting 5 Wires From a Trailer to a 7-Way Trailer Connector
  The best solution for your situation would be to use a circuit tester, like part # 40376, to wire your trailer wires to a seven way trailer connector, like part # A7WCB. Wiring by function is the best way to make sure you have the trailer connector wired correctly. Be sure you know what the black wire function is on the trailer. It will probably be for a twelve volt battery or for reverse lights, but it could be used for something else. The location for the black wire in the connector...
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• Wiring Lighting Functions Only on Trailer Side Connector # A7WCB
  You cannot always go by color because not everyone wires trailers/vehicles the same. So what you can do is wire the connector, # A7WCB by function. On a 4-Way, trailer side, the covered pin will be the ground wire. Next to that will be the running light wire, followed by left turn/brake, and finally right turn and brake will be at the end. On the back of the 7-way, trailer side connector, where the wires attach, make the following connections: Ground = 7 oclock position Running...
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• Determining Wire Functions on Trailer with Non-Standard Wire Colors
  Since the wiring on your trailer doesn't use the standard colors the best method for determine their function is to simply apply 12V power to each one to see which lights they activate. Once you determine the function for each of the wires you will just need to connect them to the corresponding terminal on the 7-Way connector. I have attached a wiring diagram for a 7-Way that you can use for reference.
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• Why Would New Self-Adjusting Trailer Brakes Seem Weak
  We find that at times the self-adjusting brakes need to be "manually" adjusted the first time when they are installed. You can do this by going to a parking lot with the trailer attached. Then drive the trailer in an empty parking lot and apply the brake a number of times to get the proper adjustment. Each time you apply the brakes with either the pedal or the manual override lever the adjustment wheel will click tighter.
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• How to Connect a Trailer-Side 7-Way Blade Connector # A7WCB to a Trailer With 5 Wires
  We offer a trailer-side 7-way blade connector that can be attached to the 5 wires on your trailer, part # A7WCB from Optronics. The linked video illustrates how this part installs. Since your trailer has only 5 wires some of these pins will not be used. I have attached a photo showing both sides of a trailer connector with notations for a typical wiring configuration by function and color. Although these pin assignments are typical there is no guarantee that your trailer is wired the...
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• Wiring Options for an Electric Winch Powered by an Additional Battery
  The easiest way to wire the battery for your winch will be to use the 7 way connector on your vehicle if you have one on your 2006 GMC Truck. You can get a 7 way trailer connector like part # A7WCB and use the Jacketed 2 Wire, part # 10-2-1, to connect a wire for the power and a wire for the ground in the connector. You will then run the ground wire, or white wire, to the negative terminal on the secondary battery and run the power lead, black wire, to the positive terminal on the battery....
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• Electric Trailer Brakes are Not Working on Trailer with Breakaway Battery
  The power coming from the brake controller in the vehicle to the brake magnets should still pass through a breakaway system battery even if the battery has low voltage. But it would be worth inspecting the wiring and fixing any pinched or damaged wires as needed and cleaning away any corrosion. Usually weak electric brakes are a result of the brakes not being adjusted out enough so there is little contact between the shoe's pad material and the inside of the brake drum. Adjusting the...
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• How to Determine the Functions of Trailer Wires to Install a New 7-Way Connector
  The easiest way of determining the functions of the wires on your trailer is to apply power to each one individually using a separate 12 volt battery and see what lights up. Then all you have to do is label the wires and attach them to a trailer side 7-Way such as # A7WCB. I have linked a video showing an example installation for you. Since there is no standard for wire color and function the wires will have to be tested to determine the functions.
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• Is Trailer Battery Being Able to Backfeed to Truck Battery a Problem
  In order for your truck battery to be able to charge your trailer battery it will have to have a connection to it that is going to have voltage like you tested. What you have is normal and the only possible downside would be if your trailer battery is basically dead and your truck battery ends up draining itself (if left connected for a long time) trying to charge it. When two batteries are connected they will seek to equalize the voltage between them. Some truck 12 volt accessory circuits...
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• How to Make Coiled 7-Way to 7-Way Tow Bar Wiring Extension
  I have a solution for you, but surprisingly we don't offer a coiled 7-way to 7-way extension for flat towing. What you would need is to start with the part # 54006-044 and then wire it to the part # A7WCB so that you have a coiled 8 foot long 7-way to 7-way. If you needed a socket you would need part # PK12703. For just replacement bulb and sockets you would want part # 294-0774.
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• Protecting Trailer's 7-way Trailer Connector from Moisture
  Surprisingly enough, we don't offer a cap that would slip over the 7-way connector on your trailer and protect the contacts from the elements. A light coat of dielectric grease, part # 11755 would act to exclude moisture form the connector. To protect the connector, I've seen folks simply use a ziplock bag and a rubber band to secure it. It's not the most elegant solution, but it's inexpensive and it works.
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• 2013 Ford F-150 With Factory Brake Controller Will Not Recgonize that the Trailer is Connected
  On the 2013 Ford F-150, the trailer connected signal is activated through the electric brake circuit. Typically the 5th wire on a 5-way plug is wired for the reverse light circuit and used with surge or hydraulic brakes. If the circuit is not completed through your adapter or if the adapter is wired for the reverse pin and not trailer brake pin on your truck's 7-way, then you will not have the correct trailer electric connection. The plug adapter that you are using may be reading the...
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• Trailer Left Side Brake, Turn Signal, and Running Lights Not Working
  Since everything is working on the truck side the issue must be on the trailer side. I have included a picture that shows the pin functions of both a vehicle and trailer side 7-Way. You will need to check the configuration on the trailer side to determine if it matches up to what the truck side has. In the pictures though you have to ignore the colors and focus only on the functions. On the vehicle side if you are looking at the pins the left turn signal and brake lights are in the 9...
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• Will 12V Blade On 7-Way Charge A Camper Battery or Refrigerator While Driving
  For the battery, you can put a maintenance charge on your trailer battery with the 12 volt accessory circuit of the 7-way. The 1:00 position of your 7-way carries this circuit. You would just need to run a length of 10 gauge wire like part # 10-1-1 from this pin to the positive terminal of the battery. This won't charge a dead battery, but it will keep the battery topped off when you are towing the trailer. Because the power draw from your refrigerator will not be sufficiently covered...
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• Troubleshooting Trailer Brake Controller That Doesn't Show Trailer Connection
  Sounds like you have some corrosion on your trailer wiring connector which is preventing your controller from sensing a trailer connection and being able to activate the trailer brakes. This is a very common problem and all you typically have to do is take some sandpaper to the pins on the trailer connector and you'll get a solid enough connection for the controller to start working again. I also attached a help article on brake controller troubleshooting for you to check out as well.
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• Troubleshooting 7-Way Mercedes Vito LED Problems
  German vehicles notoriously do not like towing trailers with LED taillights. What you described sounds like a case of this where the vehicle is looking for more amperage draw and the LEDs just don't have it. For a 7-way adapter designed for German vehicles towing LED lighted trailer to prevent the bulb out issue we have the part # C57003. This will plug right into the 7-way you have.
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