A saga about electrical equipment: wiring diagram for UAZ “Loaf”

The recognizable appearance of the UAZ “Loaf”, the legendary van first produced by the Ulyanovsk Automobile Plant back in the 60s of the last century, is familiar to almost every resident of the post-Soviet space. The multi-purpose all-terrain vehicle remains in demand to this day.

Of course, over the many years of production, the UAZ-452 model has been modernized many times, and new vehicles under different indices have been created on its basis. Despite the updated platform, suspension, different engines, nothing fundamentally new could be invented with the design of the UAZ. However, the conversation will not be about the exterior of the famous van; beauty, they say, is in the eye of the beholder, but about the electrical circuit of the UAZ “Loaf”.

What is included in the electrical circuit?

What features do automotive electrics have on old cars produced by the Ulyanovsk Automobile Plant?

Electronic components

The electrical circuit of the UAZ 452 itself is quite simple - single-wire.

By its design, the wiring diagram of a UAZ390995 or other model is characterized by the following solutions:

1. The vehicle body is used as the mass.
2. Any electrical equipment of the old-style circuit on a UAZ 409 or other model, as well as actuators, are equipped with a negative terminal, which is connected to the car body. According to experts, in general this scheme is imperfect.

According to the operating instructions for electrical equipment, the driver must periodically diagnose the condition of the integrity of the contacts. We are also talking about their oxidation. If the driver notices the presence of oxidation on the terminals, he should treat them using fine-grained sandpaper.

Engine compartment

In this case, the engine compartment is located directly in the passenger compartment in accordance with the design of the car.

Access to the electrical circuit and other mechanisms and assemblies is made from the interior, as a result of dismantling the cover, which:

1. Designed to protect the motorist and passenger from exhaust gases entering the cabin.
2. Allows you to protect the car interior from the penetration of dirt and dust.
3. Performs the function of an additional heating device, in particular passively, as a result of heating.

Engine compartment of an AUZ car
Previously, the UAZ 396255 and other models with a carburetor used an engine from the legendary Pobeda, which was later replaced with a more improved and modern unit. In particular, it means a Volga engine. This decision at one time, back in 1964, was facilitated by the serial launch of a production line at the ZMZ enterprise. Despite the fact that many domestic car enthusiasts claim that the UAZ 390994 injector circuit in the engine compartment is located in an inconvenient place due to the lack of a hood, this is not so. Decades of operation have proven that the absence of a hood in no way affects the diagnosis and maintenance of the car.

Passive safety

The very design of the domestic Loaf with the absence of a hood at first raised many questions in terms of the safety of the driver and passengers. As a result of several dozen crash tests that were carried out back in the early 70s of the last century, it was revealed that the car is no less safe when compared with other domestic cars. As the results showed, in the event of an accident, both the driver and passengers of the car have a good chance of avoiding injury in an accident.

basic information

Fuses in a UAZ Bukhanka car are located in a special mounting block, which in turn is located in the air inlet box on the left side of the vehicle. The mounting block includes all the most important sections of electronic circuits, while supplying them with the necessary fuses and relays. The fuse box of the UAZ Bukhanka car consists of two lines with fuses and this entire structure is secured with a nut to the vehicle body. If you decide to remove the fuse lines, you will need to disconnect the battery.

The main elements of the electronic circuit include:

• Accumulator battery;
• Electronic fuel pump;
• Fuel mixture purification filter;
• Injectors;
• Engine control unit;
• Electronic ignition coil;
• Spark plugs;
• Idle speed sensor;
• Crankshaft sensor;
• Air damper sensor;
• Tachometer;
• Fan motor cooling the radiator;
• Electronic fan motor control relay;
• An indicator that monitors engine performance;
• Diagnostic connector.

Wiring diagram UAZ Bukhanka

If any failure of electronic equipment occurs, the current in the node that is responsible for this device will increase, resulting in a short circuit. The wire through which the current passes to the fuse burns out and melts, as a result of which the circuit breaks and the device turns off, but its integrity is maintained. That is, thanks to fuses, the main parts are protected from overheating in the event of a short circuit.

How to properly remove and install the mounting block?

If the electrical circuit is made with high quality, it will greatly facilitate the process of installing and removing electronic equipment. So, the algorithm for removing the mounting block:

1. Disconnect the wiring from the negative terminal of the battery;
2. Open the hood and remove the cover from the fuse and relay box. To do this, you need to press out 4 plastic latches;
3. Move the rubber cover;
4. Disconnect the upper block of the wiring harness from the block;
5. We unscrew the 2 nuts that secure the block;
6. We take out the block from the compartment, which is located in front of the windshield;
7. We disconnect the lower blocks of the wiring harnesses from the block;
8. Install fuses and relays in reverse order.

Repairing the mounting block involves replacing printed circuit boards. So, the algorithm for repairing the mounting block:

1. Remove the mounting block;
2. Remove the 8 screws that secure the bottom cover;
3. Using a screwdriver, open the bottom cover;
4. We check the condition of the tracks along which the current passes and the quality of soldering. If defects are detected, they must be eliminated, but if this is not possible, then completely replace the unit;
5. Install the mounting block in reverse order.

Features of electrical equipment

So, what features does the UAZ 452 electrical wiring diagram have? At the time of the start of production, the most difficult moment for the engineers and designers of the enterprise was the search for the highest quality elements and components.

In particular, we are talking about parts for the vehicle lighting system, as well as ignition, which is especially clearly seen in how the car’s cabin is filled:

• control elements for various transport systems;
• control devices for monitoring the condition of components and mechanisms.

External optics

At that time, designers had to resort to many freelance solutions in order to establish mass production of cars.

1. The UAZ electrical circuit includes an optics switch, which was borrowed from the GAZ 69. By the way, the latter is the predecessor of the Bukhanka.
2. In addition, almost all the optics were borrowed from the GAZ 64 - these are lights, etc.

Ignition system

New modifications

Since 1985 the car has undergone changes. They can even be called quite significant. It is also worth considering that in recent years the electrical circuit of the UAZ 452 has been quite seriously modernized. And the basic equipment itself has become noticeably richer. Now the injector has become a modification for the UAZ Bukhanka. The manufacturer abandoned carburetor systems and released a more economical and modern injector for the UAZ Bukhanka. The electrical equipment of the UAZ has become more progressive.

The dashboard has also been transformed. The most noticeable changes were: an additional starter relay, additional resistance in the battery ignition circuit. However, most Bukhanka owners upgrade their vehicle themselves. And the dashboard is the first step to modernizing the interior.

In the basic configuration, the dashboard does not look impressive, so most drivers decide to upgrade its appearance. A solid overlay is installed on the panel, which makes it more visually interesting. This overlay is freely available, and buying it is not particularly difficult. The dashboard in the UAZ 452 is all-metal and does not decorate the interior. Modern panel trim is mostly made of plastic and serves as a good decoration for this car.

Another drawback in the old Loaf is the lack of electric windows. However, power windows can be easily installed yourself. They will fit perfectly into the electrical circuit of the UAZ 452. But neither the installation of window regulators nor their initial absence in the electrical wiring is the main problem of the poor configuration.

troubleshooting

On any domestic car, problems periodically arise in the operation of electrical equipment. If you notice that the UAZ wiring is not working correctly, you need to diagnose it and check all the elements. If there are any malfunctions in the operation of electronic devices, first of all you need to check whether the fuses in the mounting block have burned out. If everything is fine with these elements, but the equipment still does not function, for example, if we talk about optics, then you need to check whether the light bulbs are working. If the lamps themselves are working, it is necessary to test the electrical part using a tester (the author of the video about testing car wiring is Ramil Abdullin).

If the Loaf refuses to start at all, you need to do the following:

1. First of all, check the functionality of the battery.
2. With the battery charged, use a tester to test the circuit from the coil to the generator; often the reason for the inability to start the engine is breaks in the wiring. If there are breaks, the wires should be changed. If there is oxidation on the contacts, they should be cleaned.
3. Starting the power unit will be impossible if there is no spark. To diagnose the presence of a spark, remove the high-voltage cable from the spark plug and bring it to the body. When you try to start the engine, a spark should jump between the cable and the body.
4. If there is no spark, the problem may be carbon deposits and deposits on it. By the way, carbon deposits are often the cause of unstable engine operation and tripping. To get rid of such a malfunction, it is advisable to clean the spark plugs; step-by-step instructions for this process are presented here.

Instructions for installing and configuring the ignition on a UAZ

Starting the engine of any car is possible due to the ignition of the combustible mixture in the cylinders of the power unit. To ensure normal operation of the engine, proper adjustment of the ignition system (IS) is necessary. In addition, all elements, including the coil, distributor of the UAZ vehicle and other components must always be in working order.

How is the ignition circuit installed, configured and adjusted on the AUZ 417 or any other? We will talk about this below. But first, let's understand the principle of operation of the node, as well as the types of SZ.

Operating principle of SZ

SZ diagram and designation of its elements for old UAZ engines

As already said, the ignition on an UAZ performs one of the main functions when starting the power unit. Thanks to this system, the procedure for igniting the air-fuel mixture in the cylinders of the power unit is carried out by supplying a spark.

The spark is directly supplied to the spark plugs; one spark plug is installed on each cylinder. All of these safety devices operate in sequence mode, igniting the combustible mixture in the required period of time.

It is also necessary to take into account that the ignition system on cars not only provides a spark, but also determines its strength.

The vehicle battery is not able to produce the voltage and current required to ignite the mixture, since this device only produces a certain amount of current. The help comes from the ignition system, the purpose of which is to increase the power of the car’s battery. As a result of using the SZ battery, it is possible to transmit sufficient voltage to the spark plugs to ignite the mixture.

Types of ignition systems

Contactless SZ circuit with switch for UAZ

Today there are three main types of ignition systems that can be installed on cars:

1. Contact SZ. It is considered obsolete, but continues to be successfully used on domestically produced vehicles. The principle of operation is that the system produces the necessary impulse, which appears due to the operation of the distribution component. The contact-type device itself is simple, and this is a plus, because in the event of a breakdown, the driver can always diagnose and repair it himself. The cost of replacement components is not high. The main components of a contact type system are a battery, a short circuit, a drive, spark plugs, a capacitor, and a breaker with a distributor.
2. A non-contact ignition system called transistor. Many vehicles are equipped with this type. When compared with the type described above, the system is characterized by a number of advantages. Firstly, the generated spark has greater power, which is due to the increased voltage level in the secondary winding of the ignition coil. Secondly, the contactless system is equipped with an electromagnetic device that allows for stable operation, as well as energy transfer to all nodes. As a result, with proper tuning of the internal combustion engine, this allows not only to increase operating power, but also to save fuel. Thirdly, it is convenient in terms of node maintenance. To ensure long-term performance, after setting up and installing the distributor drive, this element must be lubricated from time to time. To ensure normal operation, the element is lubricated every ten thousand kilometers. As for the disadvantages, it is the difficulty of repair. It is impossible to repair the device yourself; this requires special diagnostic equipment, which is only available at service stations.
3. Another option for SZ is electronic, which is the most technologically advanced and expensive today, which is why new vehicles are equipped with it. Unlike the two systems described above, the electronic ignition system is characterized by a complex device that ensures the functionality of not only the torque, but also other parameters. Currently, all modern cars are equipped with electronic systems. The key advantage is a more simplified procedure for setting the advance angle, as well as the absence of the need to periodically check the contacts for oxidation. In practice, the air-fuel mixture in engines with electronic combustion almost always burns completely. This type also has its disadvantages, in particular in the matter of repairs. It is impossible to produce it with your own hands, since this requires equipment. Detailed instructions for adjusting the ignition using a light bulb are presented in the video below.

Video “Designation of electrical circuit elements in UAZ”

A detailed designation of all the sensors and regulators of the electrical circuit in the Bukhanka’s interior is presented in the video below (the author of the video is Xodor).

The UAZ-452 has received a variety of affectionate nicknames over the years of operation: “Loaf” and “Loaf” - for its external resemblance to a bread brick, “Tablet” - for reliable service in medical organizations. It is noteworthy that its design and individual systems - transmission, body or wiring diagram of the UAZ 452 turned out to be quite durable. Perhaps this was the only car in those years capable of reaching the most remote places for humanitarian purposes.

The famous Bukhanka has become a multi-purpose vehicle for rural areas

Platform for conveyor models

The “Loaf”, which became famous, thanks to its all-metal body, the “452” model served as a platform for the creation of an entire line of vehicles:

1. UAZ 2206 – a minibus designed for 11 people;
2. UAZ 3962 – vehicle for emergency medical services;
3. UAZ 396255 - a civilian modification of an ambulance for the needs of rural areas;
4. UAZ 39099 – promoted under the name “Farmer”. Designed for 6 passengers and 450 kg of cargo;
5. UAZ 3741 – a van for transporting 2 passengers and 850 kg of cargo;
6. UAZ 3303 – an onboard vehicle with an open body;
7. UAZ 3904 is a cargo-passenger version that combines the convenience of an all-metal body for passengers and an open body for cargo.

For reference: in all modifications, the electrical wiring of the UAZ 2206 is taken as a basis, from which, for each model, unused components that perform certain functions in the car interior have been removed.

Meet UAZ 452

The car was a cargo-passenger version of an off-road vehicle with a 4x4 wheel arrangement. The Ulyanovsk Automobile Plant mastered production of the model back in 1965.

You can evaluate its capabilities by watching the following video:

The UAZ 452 is capable of transporting cargo weighing up to 700 kg in the back. In addition, it can tow a trailer weighing 850 kg. The vehicle became very popular not only in Russian off-road conditions, but was also successfully used in large cities in various capacities (pictured in the article).

In particular:

1. Like a traffic police car;
2. As a fire engine;
3. Ambulance car;
4. Grocery store;
5. Utility vehicle, etc.

The famous Barefoot on the basis of UAZ 452 - a road train in the Izmailovo Central Park of Culture and Culture

Electronic components

The electrical wiring of the UAZ 452 was a simple single-wire circuit.

Structurally, it had the following solutions:

• The role of the second wire was played by the metal body and the components and assemblies attached to it;
• All electronic components and actuators had a “-” displayed on the housing. The cost of such a solution justified the imperfection of the scheme.

For reference: The instructions provided for regular checking of contacts. When oxidized, they should have been cleaned with sandpaper.

Power unit

The engine compartment is located directly inside the car, as this is due to its design.

Access to components and assemblies is also provided from the passenger compartment by removing the cover, which:

• Provided protection for the driver and passengers from the penetration of exhaust gases;
• Protected from dust and dirt;
• Served as an additional heating element (passive - from heating).

The high engine layout contributes to the vehicle's cross-country ability in off-road conditions

The previously used engine from Pobeda was replaced with a more modern engine from the 21st Volga. This was facilitated by the launch of a production line at the Zavolzhsky Motor Plant in 1964.

Note! Despite some skepticism regarding the inconvenience of servicing a cabover car with your own hands, years of operation have proven that there are no difficulties.

Passive vehicle safety

The design of the "Baton" with a cabover layout also initially raised a number of questions regarding safety. However, a series of crash tests conducted back in 1971 at the Dmitrov test site proved that in most emergency situations the driver and passengers of the UAZ 452 have a chance to avoid injury.

A striking example of comprehensive testing of “Tablets”

Differences between electrical systems

Modernizations affected the service conditions of cars of different years of production.

The car does not cause any particular difficulties when carrying out routine maintenance with your own hands, however, the electrical systems have differences, the reasons for which were:

1. Modifications of power units;
2. Changes to the instrument panel;
3. Installations of lighting and side lights of a new generation.

Read also the article “Wiring Moskvich 2140: two cars under one index.”

Original photo of the 1974 model documentation included with the car

Features of electrical equipment

For designers, a more difficult process in those years was to find high-quality components to equip the ignition and lighting systems.

This can be clearly seen from the filling of the cabin:

• vehicle system controls;
• control devices.

Due to a shortage of controls, the UAZ received rather “variegated” elements

External lighting

Everything that could be obtained was used to ensure uninterrupted supplies to the factory conveyor.

In particular:

• from the predecessor of the Bukhanka, the GAZ-69, the factory workers borrowed a foot-operated light switch;
• From GAZ-24 headlights, etc.

The design of the GAZ-69 switch was successfully used on the 452

Ignition system

Since the Volgov engine was installed on Loaves and Bukhanki, the UAZ 452 wiring for the ignition system was almost completely copied from it.

The simplicity of the design made it easy to maintain the car away from garage conditions

Period from 1965 to 1984

During this period, the automaker equipped its products with electrical components available to the domestic industry. Some of them were known for a long time, others were experimental, as evidenced by videos from previous years, and which had to prove their suitability.

Connection diagram for headlights on UAZ 452 first editions

Lighting control

In particular, the controls and a number of main units migrated from its predecessor, the GAZ-69. Thanks to this, the price of the car remained the same.

On models of the first years of production, a foot light switch was installed, which had several operating modes:

1. The first position activated the circuit for switching the low beam headlights and side lights;
2. In the second position, the low and high beam headlight circuit was activated.

For reference: Turning on the headlights (low or high beam) led to the turning off of the front side lights.

Foot switch for headlights and parking lights

The modernized light switch has a different operating algorithm:

1. The first position supplies power to the side lights only;
2. The second position is side lights and low (high) beam headlights.

Caution: This algorithm with non-switchable dimensions is a mandatory requirement for passing MOT. The factory instructions give recommendations for reworking the old circuit, in which it is important not to mix up the contacts of the foot switch.

The most correct option is to replace the old switch with a modern one, which uses only 3 contact groups.

Also, on older versions of the “452” there was no alarm, so in the electrical diagram:

1. An RS-57 breaker relay was installed (mounted in the wiring gap from the “+” terminal of the battery to the direction indicator switch);
2. The middle contact of the relay closed the indicator light on the instrument panel.

See also the Ural motorcycle wiring diagram.

Ignition system

Ignition of UAZ 452 model 1968

Also on the “452” contact ignition was installed:

1. The “+” wire from the battery supplied power to the ignition coil;
2. From the coil, the high-voltage wire transmitted the impulse to the breaker (distributor) and further to the spark plugs.

Period from 1985 to 2013

In later modifications, with the advent of injection, some changes were made to the ignition:

1. An additional resistance was installed in the “battery-ignition coil” circuit;
2. A separate wire from the starter was laid to the coil wire connection terminal (past the additional resistance)
3. On later models, an additional starter relay was installed in the circuit.

Control devices UAZ 452

For reference: UAZ vehicles also have different control devices. Some machines had an ammeter installed instead of a voltmeter. The UAZ 452 wiring made it possible to connect a voltmeter into the wire gap between the battery and the ignition system.

Conclusions: along with the car, the electrical circuit also changed. This factor should be taken into account when carrying out scheduled repair work in order to eliminate emergency situations.

See also the Moskvich 412 wiring diagram.

Electrical wiring diagram

The top picture shows a non-contact version of the car's electrical wiring in color; the bottom picture shows an older model.

Old style UAZ 3303 wiring diagram

The electrical circuit of the UAZ 3303 generator shown separately is shown above.

The circuit having an ignition system with contacts is taken from 469. There is a radio receiver on the circuit, this is interesting.

Electrical circuit of UAZ 469 similar to 3303 with contact ignition system

In conclusion, I present another one from an onboard UAZ 33036 that is newer, but not yet fuel-injected.

Wiring diagram for loaf with carburetor engine

To connect electrical appliances to the system of a car with a carburetor, an old-style circuit is used - a loaf designed for UAZ cars produced in 1954 - 1984.

Why might you need a wiring diagram for such a car? The need for instructions for wiring in a car may arise not only if some defect that interferes with the operation of the vehicle is corrected, but also when the wiring is re-installed.

It is worth remembering that there are two circuits for a car with a carburetor engine. The first is a simple one, in which there is no electronic carburetor control unit (this element appeared after 1984 and is not included in the old circuits).

terms of Use

Experienced car enthusiasts assessed the car modification differently. In comparison with its predecessor - UAZ 469, the new “three hundred and fifteenth”:

1. Became more comfortable, which was facilitated by alterations to the interior and chassis;
2. It lost its off-road qualities because it received gearboxes with changed gear ratios.

In practice this was expressed as follows:

1. When used in off-road conditions, the old 469 easily overcame mud thanks to its “military bridges”;
2. The new UAZ could be “buried” in swampy areas due to the installation of “civilian” bridges;
3. The maximum speed of “469” did not exceed 90-100 km/h on the highway;
4. The new UAZ 31514 accelerates to 120-130 km/h.

Conclusions: the appearance of the “civilian” version allowed the Ulyanovsk Automobile Plant to maintain its leadership among domestic SUVs. UAZ cars are still popular vehicles for many municipal and emergency services.

To ensure the functionality of all electrical devices on any car, an electrical circuit is used. In this article we will talk about the legendary domestically produced cars - UAZ. What is the electrical circuit of the UAZ Bukhanka car, what are its features - read about it below.