To transport relatively small oversized cargo, many motorists use car trailers. This method is quite convenient, as it requires installing a towbar on the car and removing the electrical contacts for the trailer. You need to know that the trailer connection diagram (pinout of the towbar socket) often causes difficulties during installation, so you have to pay special attention to it.
Without a working electrical part, it will not be possible to use the trailer to its full potential, as it will be unsafe for others. Road users will not be aware of the driver's upcoming maneuvers (the turn signals and stop signals will not work) and the braking system will be ineffective on the vehicle assist device.
To connect the towbar to a vehicle, it is recommended to follow the following step-by-step algorithm:
- It is customary to install the machine on an inspection pit or on an overpass for further convenient work with the equipment. To eliminate a possible short circuit, you must remove the battery.
- All things are removed from the trunk, including a spare tire and some tools. The upholstery is unfastened from the floor from the clips, and all rubber mats are removed.
- We bring the towbar to the installation area. Using convenient methods at hand, we fix it in this area, marking the places used for subsequent installation of fasteners.
- We drill the marked area, having previously marked the corresponding points or use a prepared jig.
- The resulting holes must be treated with protective anti-corrosion materials (primer and paint). This will significantly increase the operational resource of this area.
- Using bolts and washers, fix the tow bar in its place. It is recommended to tighten using a torque wrench, and the threads can be tightened.
- Next, we drill two more holes in the bottom of the trunk and the bottom of the side member. For this operation it is worth using reinforcing pads. Such an operation will make it possible not only to tighten the metal connection, but also to distribute the load on the body.
At the final stage, the bolts are threaded and the linings are fixed. After this, you can install the electrical parts, where you will need a wiring diagram for the towbar socket. Motorists choose one of the convenient methods that are suitable specifically for a specific car. The electrical diagram for connecting a trailer to a car is well described in the video.
Car trailer socket pinout
Traditionally, pads with 13 or 7 connector connectors are used. Which of them is more comfortable for a motorist to use in real conditions, it is worth deciding on the current conditions. Both of them are workers and meet in action.
For garage conditions, choose a standard or universal scheme. More relevant is the standard trailer connector pinout. According to the technology, it uses 7 or 13 connected wires. The number usually depends on the make of the car.
The principle of operation is to form a quick connect socket where the input wires from the vehicle will connect to the wiring on the trailer. In this case, while performing the corresponding actions with lighting devices from the passenger compartment, the operations will be duplicated on the rear side of the trailer.
Application of the standard method
Old domestic cars do not have an autonomous control unit for control. Craftsmen independently connect the contacts to a 7/13-pin socket using third-party wiring. In most cases, no branching is used. In fact, the car enthusiast’s task comes down to ensuring the correct operation of the light optics.
A convenient 7/13-pin socket is purchased in advance. It is connected in such a way as to provide a connection to the harness suitable for the rear optics of the car. During diagnostic work, a technological window is used. Some models have a special connector for outputting the contact.
It is important to know that you can use special connecting clips to remove cables from the harness installed in the car, and it is also possible to strip down the copper wire and then solder a new cable for removal.
It is important to properly insulate the soldered assembly in the future. To reduce errors to a minimum and speed up work, it is worth stocking up on instructions in advance, which indicate the wiring in auto electrics. This is what the towbar connection diagram is based on.
Using standard methodology
This method is relevant for owners of modern cars. This is due to the fact that such transport has a much more complex wiring structure. In such a situation, it is unlikely that it will be possible to do without a coordination block. He plays a responsible role in the process, as he constantly monitors the condition of the rear optics. If the node detects that current consumption is exceeding the norm, it will be able to send a corresponding warning signal to the driver.
Installation of a matching unit is in demand when it is necessary to properly configure the transmission of control signals using multiplex buses. The installation process in this case is carried out according to the following scheme:
- The matching block is placed in the car's wiring. For this, a circuit with connectors is used. It makes working with it much easier.
- We activate the block. After switching on, the corresponding signals will be sent to the rear optics. Such actions will allow the unit to neutralize the recognition of the connected device. This will provide the ability to quickly connect electrical equipment to the tow bar.
- In some car models, the trailer and block connectors may not correspond one to one. They will be visually different from each other. This is often due to the use of different electrical connection technologies by trailer manufacturers.
- Those motorists who have little experience working with electrical appliances should not disassemble non-joining modules on their own. It is advisable to entrust this work to specialists.
- Otherwise, you will have to ring each element separately, looking for contacts to connect.
You cannot drive on public roads without a properly connected socket. This is fraught with fines and other administrative penalties.
A towbar is one of the most important elements of a car if the car is used to transport large loads in a trailer. But when buying a trailer, many motorists are faced with the issue of connecting the towbar with their own hands, we will talk about this below. You can find out what the pinout of the towbar socket is. Also learn how to connect the device correctly.
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Installation
Installation of the towbar is carried out in the following sequence:
- The car is driven onto an overpass or inspection hole. De-energize the vehicle wiring; to do this, disconnect the battery.
- Remove everything in the trunk. We are talking not only about personal belongings, but also a repair kit and a spare wheel. You should also remove the upholstery by disconnecting all the clips.
- Place the towbar at the installation site. Fix the device, correctly mark the places where the fasteners will be installed.
- Next, you need to drill holes wherever the fasteners will be installed. To avoid possible malfunctions in the future, the holes for fastening components must be treated with an anti-corrosion agent. This will help increase the service life.
- Using bolts and washers, install them into the holes and tighten them well using the appropriate wrench.
- Then, you need to make two more holes inside the trunk and at the bottom of the spar; use reinforcing pads while working. This will not only strengthen the fastening, but will also help relieve the load from the body.
- Next, the bolts are inserted and the linings are installed. The final stage will be the installation of the electrical part. To do everything right, we recommend that you listen to the tips you will learn about below. Choose one of two methods. You can learn more about installing a tow bar in the video below.
How to connect the towbar socket?
To correctly connect a car trailer and a towbar fork with 7 or 13 connectors, you need to figure out what scheme you will use to connect. Connecting a towbar at home is carried out in accordance with one of two schemes - standard or universal. The standard option of connecting a smart socket with 13 or 7 connectors to the electrical wiring will be relevant if certain connectors are located on the device and the car trailer. Thanks to the contacts of the connectors, a connection is possible, then the car enthusiast can carry out all the work in the absence of a trailer connection diagram.
Designation of connectors in the socket for mounting towbar wiring
The essence of the action will be to correctly connect the contacts of a smart socket with 7 or 13 connectors with a socket. Often the pinout of the towbar socket and its approval are indicated in the service book for the car. But if, when connecting connectors of a smart socket with 7 or 13 contacts, for proper coordination with the trailer, it is necessary to make changes to the electrical wiring diagram, then this method will not be relevant. Car enthusiasts have to use a universal method, so we are ready to help you understand each of them.
Standard method
Most old domestic cars do not have a control and coordination unit. A car enthusiast can connect a 7- or 13-pin smart socket to an electrical system using existing wiring. In this case, a person saves himself from the need to use any splitters. That is, in essence, connecting a towbar comes down to connecting the wiring to the car’s electrical system so that the optics on the trailer work correctly.
In this case, the first thing you should do is study the diagram for connecting a smart socket with 7 or 13 contacts to the matching unit. The purchased socket is connected so that the contacts are connected to the rear optics harness block of the car. The appropriate connectors are used for this.
When diagnosing the rear optics, you can identify a special small window. Some manufacturers equip optical housings with additional connectors so that, if necessary, the motorist does not face the problem of replacing a light bulb. But be prepared for the fact that after the work there will be one more wiring left; you will need a second turn signal to the car’s trailer with its help.
How to solve this problem correctly:
- The problem can be solved by connecting to volumetric clips.
- Before starting work, the wiring itself should be cleaned of insulation, and then connected to the cable coming from the 7- or 13-pin smart socket connector. To securely connect the electrical wires of the car trailer, you will need to solder it.
If repair work will be carried out in this way, then it is advisable to prepare an electrical circuit in the car in advance. Moreover, if this is your first time doing such work, then you will need a diagram in any case, otherwise the likelihood that you will do something wrong is very high. Therefore, when installing a smart socket with 7 or 13 contacts (such devices are the most popular), be guided by the data indicated in the diagram. A detailed connector connection diagram is shown in the photo and video.
Universal method
If you are the owner of a modern vehicle, then connecting the towbar socket is carried out using a different, universal method. This is because new cars are equipped with more complex electrical wiring, so the installation method without using a matching unit will not work. The coordination unit plays an important role during installation; one of the main options of the device is regular monitoring of the condition of the rear lights. When the coordination unit detects that the current consumption rate will increase, it will warn the motorist about the error that has appeared.
That is why most experts recommend using a matching unit during installation. Its connection is also relevant if it is necessary to correctly configure the transmission of control signals using a special multiplex bus.
So, how the installation is carried out:
- The car enthusiast needs to install a matching unit, as you understand, to the car’s wiring. The connectors should be connected correctly; if there is a diagram, then use it. Then activate the coordination unit; when turned on, you will notice that the corresponding signals will begin to arrive at the rear optics of the car. After these steps, the control unit will not be able to recognize the connected matching device. Accordingly, you can connect the tow bar without any problems.
- It happens that the connectors in the trailer and on the matching unit do not correspond to each other. In this case, you will notice that the connectors have different contacts; this happens because there are a lot of trailer manufacturers using different technologies in production today. If this is the case, and you have no experience in working with, we recommend that you contact the experts. Otherwise, you should have not only the connection diagram and pinout on hand, but you should also understand what you are doing. Many car enthusiasts, understanding what is connected to what, can solve this issue without the help of specialists, but we do not recommend experimenting with methods for solving such a problem. Cargo trailers are installed using a similar scheme.
Remember that the installation of the electrical part is important, safety on the road depends on it. Otherwise, you may not only receive a fine from the traffic police, but also cause an accident. After all, car enthusiasts are often aware of the need to brake and stop on the road thanks to the rear optics on other cars. After installation and in general before each trip, you need to make sure that the optics on the trailer are working.
Video “Installation of tow bar wiring”
The biggest difficulty in creating a road train is combining the electrical wiring of all vehicles into a single circuit. The same applies to the braking system, if provided for by the technical characteristics of the trailer. The fact is that the sockets of moving objects often differ in their design, that is, there is a discrepancy in their pinouts. Let's look at the existing diagrams for connecting a trailer to a car, depending on their modifications and the pinout of the towbar socket.
General information:
- A connector is a combination of a socket and a plug that is connected after attaching the trailer to the car's towbar. Depending on the country of origin of the machine and the towed device, the connecting elements may have a different number of contacts. As a rule, there are 7 of them, but only if we are talking about products manufactured in the Russian Federation or European companies. On cars from the USA there are mainly 13 of them.
- Socket and plug contacts are counted differently.
The conclusion is clear - to combine the electrics of “different types” of trailers and the vehicle, you need to use so-called adapters or modify the pinout of the elements.
Types of connection schemes
What to consider:
- Practice shows that when regularly connecting trailers from different manufacturers, it is advisable to install 2 seven-pin towbar sockets on the vehicle. This is much more convenient than searching for and mounting a sample with 13 connection points.
- Different car models and series may have certain differences from generally accepted (standard) schemes. For example, the dimensions are displayed not on the 7th pin, but on the 5th (diagram below).
- In addition, if the vehicle is a used vehicle, then it is not a fact that the former owner did not connect the trailer to the towbar socket in his own way. This must be taken into account and the order of its pinout must be checked. How? Check the electrical diagram of the machine of this brand and series.
If there is no “native” documentation, then the necessary information is easy to find on the Internet. But there is a nuance that is worth mentioning. It is no secret that many articles on various sites are nothing more than “clones”. Unscrupulous authors simply rewrite them, achieving uniqueness, without delving into the meaning of the text at all. Accordingly, errors “migrate” from one network page to another. Therefore, it is necessary to obtain all the information you need only from the car manufacturer’s website. They are not classified as secrets and are in the public domain. As a last resort, consult a service workshop or an electrician.
Typical towbar socket pinout options
For 7 contacts
Domestic cars
Cars from a European manufacturer
For 13 contacts
The options considered apply only to cars that are not equipped with sophisticated electronics. In more modern cars, when the ignition is turned on, the control unit begins to test the power circuits. Since a trailer is connected, the load on the corresponding lines will be increased. The on-board computer takes this as a malfunction, and the control unit issues an error signal.
Therefore, an “intermediate link” must be installed between it and the trailer circuit, leveling deviations in the circuit parameters - a matching block. As a result, the general electrical circuit takes on the following form (example):
In a specialized store they will help you choose the right modification of the BS according to the brand of car and trailer, and will also advise you on the connection procedure. This is one of the main arguments against purchasing such devices at various “bargains”, “flea markets” or second-hand.
To avoid problems with the electrical part of the trailer during the operation of the trailer, the connection point of its bundled wires to the towbar socket should be coated with sealant, and the contact groups with solid oil (lithol). The latter is necessary to prevent moisture from getting inside, which leads to oxidation of the metal pins and plates. The result is predictable - a violation of the integrity of the electrical circuit. By the way, this is the most common reason for loss of contacts some time after connecting the towbar.
It happens that you need to connect some kind of trailer, but there is no diagram at hand, and there is no knowledgeable person nearby. The pinout of the socket is easy to determine using a household multimeter. Every self-respecting car enthusiast has such a device. Its negative probe is always on the car body. The “–” terminal of the battery is connected to it.
What to do:
- Set the operating mode of the multimeter to “measure U=”, the limit is more than 12V (depending on the modification of the device, it is easy to choose). Detailed.
- Turn on the vehicle's ground.
- Next, one by one, the main lighting devices (external) - turns, brake light (by pressing the pedal), dimensions. In this case, each time, use a second probe to go through all the contacts of the socket and look for where the voltage appears. The rating does not matter, since it depends on the degree of discharge of the battery. It is clear that it will not be less than 13.4 on a working car, otherwise the battery parameters do not correspond to operating conditions. Using this simple method, you can create a socket pinout diagram in about 10 minutes. The only thing you need is an assistant (press the brake pedal, change turns, and so on).
If the trailer is old, with a broken connecting cable, then it is not difficult to make one. Suitable for each signal line. The cross-section is at least one and a half squares. For example, a bundle can be assembled from two-core samples 2 x 1.5. If you have at least basic knowledge of electrical technology, then it’s not difficult to draw up a connection diagram yourself. With a reasonable approach, the number of conductors can be reduced, given that some optical elements operate synchronously.
If the contacts in the cable plug from the trailer and the car towbar socket do not match, different connection methods are practiced - direct connection of wires, through special (volumetric) clips and a number of others. But this is a slightly different topic.
Good luck in solving the problem of connecting a trailer to your car!
When operating a vehicle with a trailer, any connection diagram for the towbar socket on a VAZ 2106 can be used. During the process of installing the towbar, it is important that all electrical equipment operates in normal mode. And it should not happen that when you press the brake pedal, the turn signals flash. In the towbar socket, all contacts are located in a certain sequence, so you can subsequently use any trailer.
How to install a tow bar on a VAZ 2106
You need to install the towbar (towbar) according to the following algorithm:
- It is most convenient to carry out all work from below the car. Therefore, you will have to use an inspection hole, a lift or an overpass.
- Disconnect the negative terminal from the battery.
- Remove the trunk trim and get rid of foreign objects.
- Mark the position of the tow bar relative to the body. Mark the location of the mounting holes.
- Make holes for fasteners. Before installing the towbar, be sure to treat it with anti-corrosion compounds, otherwise the metal will begin to rust.
- Bolts, washers and nuts are used as fastening elements. Bait them and tighten them.
- Drill two holes. One is in the lower part of the spar, the second is in the trunk. Install reinforcing pads to significantly strengthen the fasteners and remove excessive load from the car body elements.
- At the last stage, the electrical wiring is installed. It can be done in one of two ways.
Standard socket connection method
The trailer has a plug that has 7 or 13 pins. It will not always be useful, so motorists use a universal method of connecting the towbar socket. On most domestic cars of the “classic” VAZ 2101-2107 family, the installation of coordination and control units is not provided. Therefore, the socket is installed for a specific trailer. To do this, you only need to know the pinout of the plug. The socket is connected by a wiring harness to the rear light of the car.
Before connecting the towbar socket, carefully study the vehicle wiring. The best installation method is to connect the socket to the rear light using plugs. Enough for 7 plugs:
- Weight (minus battery).
- Left turn signal.
- Right turn signal.
- Stop signal.
- Parking lights.
And a couple of spare ones wouldn't hurt. In the event of a breakdown, you can quickly transfer the wires from one contact to another. Carefully study the rear light diagram so as not to make mistakes during installation. And you will have to install other fuses. Standard ones installed on a car have a current reserve of about 25% - this is the normal value used in calculating electrical circuits.
As the load increases, the maximum permissible current becomes higher, so you need to replace several fuses, maintaining a margin of about 25%.
Universal connection method
For owners of modern cars, connecting the socket will be easier. And all this is due to the fact that the wiring itself is much more complex. You will have to install a special matching unit. With its help, all optics of the tow hitch are diagnosed. And if the current consumption increases (during a short circuit), the driver will be warned. A notification will also occur if one of the lamps fails (the current consumption decreases). For this reason, experienced auto electricians advise using a matching device.
Installing a towbar socket on VAZ cars using a universal method:
- Install the matching device and connect it to the car wiring. Connect the connectors according to the diagram. To activate the matching device, you need to turn it on by applying power. The optics on the trailer will start working, depending on what signal is being received.
- In rare cases, the connectors on the matching unit and the trailer do not match. There are many manufacturers of electrics and trailers, which is why such “disagreements” happen. But if you have a pinout diagram for the trailer plug and the car’s electrical system, you can solve this problem quite quickly.
The functioning of optics on a trailer depends on the quality of installation. Carefully insulate exposed wire sections to prevent short circuits.
The trailer of a passenger car is connected to a tow bar - a tow ball device. It connects to the vehicle's wiring, allowing the driver to turn on the tail lights, fog lights and turn signals on the trailer. The electrical connection is made through a special socket - it has 7 or 13 contacts. Regardless of whether the towbar connection diagram uses 7 pins or 13, you may need a smart connector that coordinates the electrics of the vehicle and the trailer on it.
Some subtleties
On simple cars like the VAZ 2107, the connection of the towbar socket to the car is connected by wires to the standard wiring, which is responsible for the rear optics.
Sooner or later you may need to use your car to transport cargo. The standard electrical connection is carried out according to the “male-female” principle and does not present any difficulties, since the connectors are sold in all car dealerships. To ensure that soldering the connector is easy and matches what the wiring diagram shows, the wires are differentiated by color. To connect the wiring, it is better to choose stranded copper wires.
The 7-pin towbar socket pinout is the most popular today. However, electrical sockets for European cars may differ from similar devices for domestic passenger car trailers in the location of the signal wires.
The question arises: how to connect the outlet in this case? A similar problem occurs when the plug on the car has 13 pins, and the towbar connector has 7.
To connect electrical equipment, when it comes to different connectors, a special smart connector is used. It allows you to connect contacts in cases where the wiring does not match.
When choosing a socket, you should pay attention to the presence of a rubber seal on the back side to waterproof the contacts The connection diagram for a 13-pin towbar socket looks like the wires on it are located as follows:
- 1 – left turn;
- 2 – fog lamp;
- 3 – earth;
- 4 – right turn;
- 5 – right clearance;
- 6 – stop signal;
- 7 – left clearance;
- 8 – reverse;
- 9 – continuous load current;
- 10 – power;
- 11 – free;
- 12 – free;
- 13 – earth.
13 pin socket 
7-pin towbar connection diagram To properly connect the wiring, it is important to have knowledge of electrical engineering. The trailer socket connection diagram is shown in Figure 1.
Trailer connection diagram Rice. 1 Connecting the towbar to the vehicle wiring system
We place the electrical outlet on a metal frame, which secures the towbar to the car body. When purchasing, make sure that the back side has rubber seals. This is necessary to ensure waterproofing of the electrical outlet contacts.
The connection of the tow hitch to the car's power supply system is carried out where the harness block of one of the rear lights is located.
Matching block
Connecting a caravan requires attention to more than just how well the trailer's outlet circuit matches the electrical outlet on the vehicle. When we try to connect a towbar to a vehicle like a VAZ 2107, we will not have any difficulties - the wiring is installed directly. Drivers of modern cars know that the reaction of the on-board computer to a trailer can be negative and lead to problems. To avoid this, you can make one that allows you to correctly organize the operation of the electrical system.