Electrical wiring diagram for trailer connector. Car trailer socket pinout - towbar connection diagram

When transporting large cargo that exceeds the volume of the trunk of a passenger car, you cannot do without a trailer. In accordance with traffic regulations, such a device must be properly equipped to ensure safety standards. First of all, this requirement concerns lighting devices, namely, side and turning lights, as well as license plate lights. Accordingly, to supply power and control the equipment, it is necessary to combine the electrical circuits of the cargo trailer and the car; this is done using a connecting chip.

Ways to connect a towbar socket

There are two options for connecting:

• In a regular way.
• Universal.

Let's look at each of them.

Standard connection

Many modern cars have a connector for connecting the electrical wiring of the trailer, to which control wires and power are supplied. In this case, it is enough to select the appropriate plug and connect it to the trailer wiring (according to the pinout specified in the user manual).

This connection method is the most optimal, since it does not require intervention in the electrical wiring. Please note that independent manipulations with it lead to loss of the right to warranty service.

Connection in a universal way

When the connecting chip is not provided in the design, the car owner can install it himself. The only limitation for this is the presence of an on-board computer. If it is not there, then the socket is connected directly, connecting it with wires to the control circuits using special clips (Fig. 3) or by soldering.

You should first find the necessary wires; having a wiring diagram will significantly speed up this procedure. It is advisable to check the compliance of the found circuit; this can be done using a multimeter.

As already mentioned, this method is not suitable for vehicles equipped with an on-board computer. This is due to the fact that connecting the trailer directly to the signal circuits will cause an increase in load on them, which will be perceived by the computer as a malfunction.

The problem can be solved using a special device - a matching unit, it is connected between the control bus and the trailer's electrical wiring (the wiring of the bus is indicated in the manual). We will not describe the operating principle of this device here, since this is the topic of a separate article. As a result of installing the matching unit, the on-board computer “will not notice” the connection to the trailer’s electrical wiring system.

Having figured out the connection methods, let's move on to the pinouts of the sockets. First, let's look at the classic European standards, then we'll get acquainted with their American version.

Pinout of 7 pin socket

Below is a drawing showing the wiring of a 7-pin connector (socket and plug). The typical colors of wires for Russian-assembled cars are indicated (color deviations are possible). In European machines, not all contacts on the connector may be used.

Explanation of the picture:

1. Left side turn signal control signal.
2. PTF connection (in foreign cars the contact may not be used).
3. Weight.
4. Starboard turn signal control signal.
5. Side lights on the left side.
6. Brake light control.
7. Side lights on the starboard side

Currently, the 7-pin connector is practically not used in modern foreign cars; 13-pin sockets are installed there. If the trailer has an old type plug, you can connect it to the new Euro connector using a special adapter, which is much easier than changing the connector.

Pinout of 13 pin socket

Almost all modern imported cars are equipped with this connector (if the design allows for its installation). The colors and pin numbers, as well as the correspondence table, are shown below.

Correspondence table for 13-pin connector.

Pinout of 15 pin connector

This type of connector for connecting trailers and semitrailers is an accepted standard for tractors from almost all manufacturers, including American ones. Considering the requirements for trailers of this class, a standard 13-pin connector is not suitable for powering and controlling their electrical equipment.

Matching table for 15-pin connector.

American connecting chips

Many American standards differ from European ones, and trailer hitch socket pinouts are no exception. Here are two types for your reference: 7 and 4 pin connectors.

The 7-pin socket, used in the HOPKINS model range, as well as in other cars (Fig. 8), differs from the European standard practically only in design, which allows, if necessary, replacement with a European analogue.

Designations:

1. Connecting side lights.
2. +12 V.
3. Starboard turning lights.
4. Brake light control.
5. Weight.
6. Turning lights on the left side.
7. Reverse signal.

Now let's consider a more complex option - a 4-pin connector (see Fig. 9). If you try to replace it with a European 7-pin socket, problems will arise.

Designations:

1. Weight.
2. Control of side lights.
3. Left side turn signal and brake light control.
4. Starboard turn signal and brake light control.

As you can see, the difficulty is due to the fact that the turn signals and brake lights are controlled along the same line. There are two ways to solve the problem:

1. Not entirely correct, but the easiest way: connect directly to the stops and turn signals. Note that in some cars the wiring may not withstand the additional load, so it is better to solve the problem in another way.
2. This option is somewhat more complicated, but more correct: you need to completely extend the wiring under the European connector. For example, in a Chevrolet Tahoe, to do this you need to remove the instrument panel, find wires with separate signals for the turn signals and brake lights, connect to them by stretching the electrical wires from the towbar socket through the entire interior of the car. You can make the task a little easier if you take the signal for the brake lights from the rear fender; it is displayed there on almost all cars. In this case, you only need to pull two wires.

Installing a towbar and trailer is a simple process, but the complexity is caused by the connection diagram of the equipment to the on-board network. If errors are made during the task, this may affect the safety of movement. Below we will look at what the connection diagram for a car trailer socket represents and what steps will need to be taken to complete this task.

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Direct connection diagram

Depending on the type of device and plug, the pinout diagram may be different. The fundamental difference lies in the colors of the outputs, as well as the number of pins.

7 pin circuit type Euro and RF

In 7-pin wiring diagrams, the assignment of contacts is as follows:

• 1 — left turning lamp;
• 2 — reversing lamp, turns on when switching reverse gear;
• 3 - mass pin or ground;
• 4 — right turning headlight;
• 5 — pin for illuminating the license plate and right side headlight;
• 6 — brake lights;
• 7 — left side light source.

7 pin US type circuit

The main feature of this type of device is that its circuit implies the presence of a reverse output, but in such devices there is no separation of dimensional signals. There is one output that is responsible for activating them; both the left and right lamps turn on immediately. Depending on the car model, some American-made cars do not have separate brake lights. The detailed purpose of the contacts is shown in the photo below.

User Andrey Vid made a video showing the procedure for installing and connecting the electrical circuits of an outlet.

13 pin circuit

In 13-pin devices, the connection diagram for a car trailer socket looks a little different:

• 1 — yellow output is required to activate the left turn signal lamp;
• 2 — power supply for fog lights is connected to the output;
• 3 - must be used as grounding;
• 4 — the plug of the right rotary light source is connected to the pin;
• 5 - this pin is necessary for powering side lighting and backlight sources;
• 6 — brake lights;
• 7 - necessary for powering the right row of side headlights and illumination;
• 8 — reversing headlights;
• 9 — orange contact is required to connect to power;
• 10 - pin to ignition;
• 11 - another contact is used as a ground;
• 12 - this pin is used as a spare in equipment; experts often use it to connect an auxiliary signal cable;
• 13 - ground, used directly for contact number 9.

The fundamental difference between the connector is that higher power currents can pass through its contacts. You can connect household devices of a caravan trailer and a charger for powering the battery to the power supply. These outlets can be used to connect to boat equipment, but adapters must be installed to accomplish this task. New devices can use ABS, ESP systems, as well as control models. If you install such a device, you will need smart connectors and plugs for connection.

Photo gallery

1. Scheme for connecting electrical appliances with seven contacts 2. 13-pin machine socket circuit 3. Diagram of an American 7-pin device

Electronic matching unit

The use of a matching module is necessary if you are the owner of a modern car, “stuffed” with electronics. Semipin devices are not relevant. The matching unit is designed for testing rear lights. If, during use, the device detects that the lights on the equipment consume more current than required, the car owner will be warned about this by means of a problem message. Installation of a matching module is needed to transmit control pulses over a multiplex channel.

To connect the device to the electrical component, you must connect to the signal cables. As a result, impulses to the trailer lighting sources will be supplied not from the car, but from the unit. This device must be connected to the car's electrical network.

What is required to connect the tow bar?

To complete the task you will need:

1. Socket. The device will come with a cover and a rubberized seal. Please inspect the product carefully before purchasing. All elements of the device body must fit snugly against each other; gaps are not allowed. Check the quality of the threads, as well as the condition of the fixing bolts on the contacts.
2. Buy a good single-core cable used to connect to the machine's on-board network. The cross-section must be at least 1.5 mm2.
3. Connecting connectors. Experts recommend purchasing equipment with outputs for safety devices.
4. You will need a corrugated pipe made of metal or polypropylene. It will be used to insulate the wiring. The hose length is required to be at least two meters.
5. A set of plastic mounting clamps, which are designed for fixing electrical circuits.
6. Silicone gasket. The manufacturer and color of the product do not matter.

Connection methods

There are several methods for connecting electrical appliances to the on-board network with your own hands; we will consider them in detail.

User MONSTROCHOD has provided a video that will help you understand the procedure for installing and connecting trailer lights to the vehicle's on-board network.

First way

Cars manufactured more than fifteen years ago usually do not use a matching module, so the car owner will have to install an outlet using the existing wires. This will eliminate the need to buy auxiliary splitters. While performing the task, you should properly connect the cables to the car's electrical system to ensure uninterrupted operation of the rear lights. To prevent errors, you need to carefully study the connection diagram; it should come complete with the socket. The device should be connected so that its outputs are connected to the power plugs for the rear optics in the car.

Depending on the trailer manufacturer, the optics may be equipped with additional plugs to make it easier to replace light sources. When it is necessary to connect a second turning light to a trailer, car owners are faced with the fact that there is an extra cable left.

You can get rid of this problem using different methods:

1. Connect the equipment to larger clips.
2. Before you begin the task, you should remove the insulation from the cable and then connect it to the wire that comes from the socket plug. To ensure a high-quality and reliable connection, the cables should be soldered to each other and then insulated again. This will prevent possible current leakage and ensure stable operation of the rear optics as a whole.

Implementation of this method requires the driver to understand the vehicle's electrical wiring diagram.

The Simple Opinion channel made a video showing the process of connecting a tow bar and its wiring.

Second option

This method is relevant for owners of modern cars. Newer vehicles are equipped with a complex electrical circuit, so connecting the equipment without a matching device will not work.

How to connect the device:

1. First, the matching device is installed; it must be correctly connected to the vehicle’s on-board network. Use the diagram.
2. Once the device is connected, turn it on. When activated, the rear lights will pulse. This suggests that the control module cannot recognize the matching unit, and this is as it should be. Now you can connect the tow bar.
3. In some cases, the layout of the contact elements on the device and the matching device do not correspond to each other. Connect the device using the existing circuit. If you are faced with such a task for the first time, it is better to seek help from a qualified electrician. Incorrect actions can lead to problems in the operation of the electrical component. The process for connecting cargo trailers is identical.

What needs to be taken into account to ensure long and uninterrupted operation of the electrics on a machine trailer:

1. Avoid overvoltage in the electrical network. Particularly if you use household appliances, too much voltage can cause a short circuit and fire.
2. Carry out diagnostics of electrical devices regularly, especially before leaving. The presence of defects that can be identified visually will indicate problems.
3. Before the start of the new season, perform diagnostics of electrical connections located outside the car body and trailer. To avoid problems with the wiring, sometimes lubricate the contact parts and connectors with grease or other protective materials.
4. Make sure that the wires are not hanging. Electrical circuits must be securely fixed to the body using plastic clamps. If you plan to use your trailer regularly, we recommend installing waterproof optical lighting sources on it.

The pinout of a trailer socket (from the English pin - “pin, leg”) is a wiring diagram of electrical connectors necessary for independently connecting a trailer to a car. The connection is required to ensure the safe operation of non-self-propelled trailers. The connection is made using a socket (located at the towbar) and a corresponding plug connected to the trailer wiring. Using connecting connectors, it is possible to combine the electrical circuits of technical equipment: the electric current supplied from the vehicle will operate the turn signals, side lights and license plate lights of the trailer. You may also need a smart connector that coordinates the vehicle's wiring with the trailer (on some modern vehicles with electronic control circuits).

7 to 7 socket connection diagram

The most common connection scheme at the moment is with a 7-pin “plug” (“European” connector). It is used when connecting most trailers for passenger cars. The connection diagram is shown below:

Please note: the receiving and responding parts of the device have both types of sockets (“male” and “female”). This solution is a guarantee of safety when connecting a round connector in poor visibility conditions: the relative position of the sockets eliminates the possibility of their incorrect connection or short circuits. Connectors are sold in any car dealership, and for their connection they use multi-core copper cables with different wire colors. For safe and long-term operation, it is recommended to coat the contacts with grease or lithol, and treat the place where the cable enters the socket with sealant.

Pinout of 7-pin towbar socket in passenger car trailers

To synchronize the light signals, it is necessary to pin out the 7-pin trailer socket and connect it to the vehicle's electrical wiring. The optimal locations for the socket location are technological openings for changing lamps (they have access to the sockets). If the towbar is equipped with a socket box to which all signals are output, it is enough to buy a 7-pin “plug”, connecting it in accordance with the connector diagram indicated in the instruction manual. This method is called standard. Otherwise, use a universal connection method: the wiring is connected directly to the signal circuits if there is no on-board computer in the car. The wires coming from the connector are connected to the electrical circuits of the rear lights.

Universal trailer connector connection method and pinout

To connect in a universal way, using the towbar connector, alternately connect the wire of the left turn signal of the car with the left turn signal of the trailer, the rear fog light of the car and the fog light of the trailer, etc. Carefully study the machine's wiring diagram to accurately find the necessary circuits (use a tester to check).

When connecting the wires through the towbar connector, use crimp clips or solder the wires after stripping the insulation. To connect to a car with an on-board computer, you need not only a 7 pin trailer plug, but also a matching unit - a device that is connected to the on-board circuit and is not perceived by the computer. Even with increased current consumption due to the operation of the trailer's lighting equipment, the on-board computer will not indicate malfunctions.

7-pin trailer socket pinout: important features

A simplified diagram for connecting a 7 to 7 socket involves independently determining the routing of the wires, and the greatest difficulty is determining where the corresponding conductors are connected. It is strongly recommended not to do this at random, connecting the connector contacts of the trailer in series with the indicator lamp - in the presence of digital circuits for controlling lighting devices, this method is unsafe.

Before connecting, check the electronic circuits in the trailer connector for rotted wiring in the area of ​​soldering and contacts, and for short circuits in areas of rubbing elements. After this, draw up a routing diagram indicating the colors, methods and locations of wire connections. If electrical connections are located outside the cabin, they should be covered with heat-shrinkable cambric (special insulator), and upon completion of work, check the electrical connections with a multimeter, making sure there are no short circuits.

Many motorists who are faced with periodic transportation of certain cargoes use trailers for transportation. But in order for the car to be equipped with a trailer, a towbar must first be installed on it. In this article we will look at what a trailer connection diagram looks like and how to properly install a tow bar.

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Sockets installed on the tow bar

To correctly implement a wiring diagram for a passenger car, you do not have to be a professional electrician. If you want to properly connect the device to the car's electrical network, first of all we recommend that you understand the types of sockets that can be used. A special platform is connected to the towbar equipment, and the socket is installed on it. It must be taken into account that during installation the socket should be protected as much as possible from possible external influences that could damage it.

Today there are two types of sockets:

1. For 13 contacts. Such sockets are usually used in cars in Europe and the USA. Additional contacts in the socket are used to turn on fog lights and other electrical equipment. For example, if we are talking about a trailer home, then in addition to optics it will be necessary to output contacts for powering all kinds of devices that are used in it.
2. With 7 pin pinout. 7-pin sockets are used in vehicles operating in the countries of the former USSR. In this case, contacts are used to connect side lights, turn signals and brake lights. In both the first and second cases, the contacts must be mirrored.

Photo gallery "Socket diagrams"

Designation of terminals for connecting a trailer

In order for the car towbar to be correctly connected to the on-board network, you need to know which wiring to connect to which contact.

In accordance with the diagram, which is relevant for both types of sockets, the assignment of the contacts is as follows:

1. Yellow contact. Used to activate the left turn signal and hazard warning lights.
2. One of the rear fog lights should be connected to terminal number 2, blue, if it is installed on a trailer.
3. Ground is connected to the white output, that is, grounding. This contact should be connected to the vehicle body.
4. The green terminal is used to connect the right turning light, as well as the warning light.
5. The brown element is used for left. It also powers the license plate lights on the trailer.
6. The red output is intended for connecting brake lights. Under no circumstances should the trailer be used if this contact is not connected, as this may affect the safety of movement.
7. The black terminal is used to connect the right side headlights. It should also be connected to the license plate light power supply.
8. Pink contact. The purpose of this pin is to transmit power to the reversing lights.
9. The orange terminal must be connected to power from the car battery.
10. The next element is gray and is used to connect to the ignition switch. In this case, the operation of the markers will be activated along with the inclusion of the marker optics.
11. Black and white element. This is grounding, so it is connected to the car body.
12. The output is blue and white. Typically this element is used as a spare; a signal wire can be connected to it.
13. The last pin is also the ground for pin number 9.

It must be taken into account that other colors that differ from those described above may be used to indicate the elements of the socket. However, only the most common ones in use are listed here.

Towbar Connection Guide

So how do you properly connect a caravan to your car's electrical wiring? The installation and connection procedure should be carried out in the area of ​​the harness connector, which is located in the area of ​​the rear lights. Typically, cars have a special technological hole through which lighting sources are replaced. It must be taken into account that in the course of performing this task in modern cars, difficulties may arise; as practice shows, they are caused by incorrect operation of the optical display. The very essence of the problem lies in the fact that the electrical circuit of the on-board network was initially designed for a specific current parameter, as well as resistance.

Accordingly, by independently connecting additional voltage consumers, the internal resistance parameter of the electrical circuit will drop. As a result, this causes increased current consumption, which increases power and activates various protection systems. Such a system may “think” that there has been interference in its operation and, accordingly, will regard this as a short circuit. In order to prevent this, you can additionally use a special device - an adapter characterized by increased resistance. With this adapter, the car owner can provide the most optimal power to the lights, while using alternative voltage sources.

Since you will have to additionally install a power source, this element should be connected to the car. If the adapter will not be used, then, as an option, you can simply purchase a relay for the side lights.

In general the procedure looks like this:

1. First, the tow bar is installed. Depending on the design features of the car, you may have to remove the wheels and install a special frame.
2. Then the socket is output.
3. The towbar is connected to the towbar, and all the corresponding wires are routed from it.
4. Then, in accordance with the pinout diagram, all electrical elements of the towed equipment are connected to.

To transport a large load, you need to attach a trailer to your vehicle. This can be done through the trailer hitch and a tight connection to its socket. The trailer's electrical wiring (cable) leading to its headlights, when connected to the main vehicle's wiring, will alert rear road users to various actions by the driver. To correctly connect the signals, trailer connection diagrams and towbar socket pinouts must first be prepared.

The towbar connector, also sometimes called a plug, allows you to connect the electrically conductive elements of the main vehicle connected to the trailer.

There are the following types of connectors:

1. thirteen-pin socket connector, more often used in Russia;
2. European or American standard, having 7 pins, representing seven-pin connectors;
3. special (special) connector.

The pinout of a towbar socket with seven contacts involves the use of conductors (wires) with a cross-sectional diameter (thickness) of 1.5 mm and 2 mm, namely: 6 wires of 1.5 mm each and 1 wire of 2 mm.

Pinout diagram for 7-pin towbar connector:

• “L” is the wire that goes to the left turn signal;
• “54G” - directed towards the rear fog lamp;
• “31” — negative wire (2.5 mm);
• "R" - to the right turn;
• “58R” is the wire that is responsible for the right side marker and illumination of the state license plate;
• “54” - brake lights;
• “58L” - direction to the left parking lot.

Pinout of the socket according to the 13-pin towbar wiring diagram (distribution by color):

1. Yellow - left turn signal and emergency alarm activation.
2. Blue - fog lights (if such are provided by the car design).
3. White - “minus”, also known as “ground”, negative charge (connects to the car body. Gives 35 A each to turn signals, side lights, “stops”).
4. Green - right turn signal.
5. Brown - right side lamp and license plate lighting.
6. Red - brake lights (the absence of these car lights on the trailer of your car is a violation according to current traffic rules).
7. Black - left side marker light, partial number plate illumination.
8. Pink - reversing light.
9. Orange - “plus”, “positive pole” or car power that runs on the battery, even when the car’s ignition is turned off.
10. Gray - unlike orange, this contact provides operation only when the ignition is on.
11. Black and white - a contact that has a negative charge (opposed to the positive gray contact signal in the electrics on the towbar).
12. Blue and white - a nest that remains spare; You can connect the signal wire here.
13. Orange-white - negative charge to the “orange” pin of the pinout.

Features of connecting the towbar socket

If you need to additionally attach the trailer hitch socket, it should be installed in the towbar socket, and then connect the contacts according to the pinout of the towbar connector, wiring diagram. Conscientious manufacturers include placement instructions in the box with the product they sell. If there is no such pinout, each car owner will have to determine the identity of certain contacts independently.

It is important to prepare all the necessary tools and materials for the job before you begin to loosen or tighten any bolts, screws, or other fasteners on a car, towbar or trailer hitch.

Among the mandatory tools and tools for preliminary preparation for connecting the trailer hitch (taking into account the electrical kit) are the following:

• the actual socket for the tow bar;
• dismantling devices (for removing the bumper, as an option - for trimming the rear bumper, if necessary);
• electrical tape, heat shrink;
• fastening elements, including a fastening plate;
• screwdrivers and wrenches (a set of different sizes of wrenches);
• soldering iron;
• wires (if they are not included in the kit, it is recommended to choose copper wires of the specified thickness);
• connecting terminals for the contact ends of the wires (can be sold together with the towbar, otherwise it’s easy to buy yourself at the market, bazaar or construction hypermarket);
• connection diagram for the towbar socket (preferably on paper).

For those car owners who decide to install a trailer hitch and install the socket themselves, the following rule should be taken into account: the thickness of each core in a stranded wire must be at least 1.5 mm.

How to connect a towbar socket

Connecting a towbar socket is not a difficult task, especially if you have such a universal component as a towbar connector. It is convenient when the socket and plug have the appropriate number of connectors. A socket consisting of 7 sockets corresponds to a 7-pin towbar plug, and a socket with 13 sockets corresponds to a 13-pin Euro wiring.

In this case, with the presence of a special connector, connecting the towbar consists of the usual combination of the socket and the corresponding socket. You should first familiarize yourself with the location and appearance of the connected connectors. If they visually match, you can try to attach one to the other.

A high-quality towbar socket has a cover that protects it from external influences while the towbar is not attached to the trailer.

Simplified connection

You can make the electrical connection a simpler procedure. To do this, you just need to combine some wiring into groups to create a more effective symbiosis of supplying electrical signals. So, you can splice the contacts of two reversing lights, 2 brake lights, side lights and fog lights in pairs, since they always light up synchronously when used. Use brackets if necessary to attach an additional socket.

Alternative connection option

The next way to connect the trailer hitch is to make changes to the electrical system of the machine. These changes consist of connecting the same wires leading to the rear light and signal electrics of the car's trailer with the wires from the coupling device. If your car has a more complex electrical circuit, you will have to spend a little more time connecting the wiring of your towbar than in the previous case.

If the light and signal lamps of your car operate without the participation of a special microprocessor, a suitable option is to connect a seven-channel (having 7 contacts) towbar connector. Before starting the procedure, check whether there are the required number of wires of sufficient, but not excessive cross-section. If necessary, you can make the wiring elements yourself by taking two- or three-core 1.5 mm copper wires marked “PVS”.

When making a direct connection, you must have both the towbar connection diagram and the socket diagram of your car in front of your eyes!

To connect, you need to feed one single-core wire to the turn signals, brake lights, fog and side lights, and license plate lighting. In addition, you should connect 2 wires, which are called “to ground”, and to the reversing light (if equipped). All of the listed 11 wires make up the towbar-socket wiring.

Enabling using a matching block

When connecting a trailer hitch, a modern electronic control unit requires the presence of an adapter, that is, a coordination unit between the electronic elements of the car, the towbar and the towed part of the vehicle. With this switching on, the car's rear light signals, reversing lights and other electrically dependent elements of the car will be harmoniously combined and work smoothly.

The activation of the vehicle's towbar electronics presupposes the fact that a trailer is being used, which should notify traffic participants behind about possible maneuvers with light signals. The correct connection of electrical contacts will affect the possibility of further operation of the car with a trailer in accordance with the rules.