Installation unit VAZ: full control over the on-board power supply

The power grid is one of the most important systems of a modern car, it performs hundreds of functions and makes the operation of the car itself possible. The central place in the system is occupied by the mounting block - read about these components of VAZ cars, their types, design, maintenance and repair in the article.


Purpose and functionality of mounting blocks

In any car, there are several dozen electrical and electronic devices that have a variety of purposes - these are lighting devices, windshield wipers and windshield washers, ECUs of power units and other components, alarm and indication devices, and others. A large number of relays and fuses are used to turn on/off and protect these devices. For maximum convenience of installation, maintenance and repair, these parts are in one module - the mounting block (MB). This solution is also present in all models of the Volga Automobile Plant.

The VAZ mounting block is used for switching and protecting the devices that make up the electrical on-board network of the car. This block performs several key functions:

- Switching of electrical circuits – this is where they are switched on and off using relays;
- Protection of circuits/devices from overloads and short circuits – fuses that prevent the failure of electrical devices are responsible for this;
- Protection of components from negative effects – dirt, high temperatures, ingress of water, exhaust gases, technical fluids, etc.;
- Assistance in diagnosing the vehicle's electrical system.

These units control the vehicle's power grid, but have a fairly simple design.


The design of VAZ mounting blocks - a general view

All mounting blocks used on the models of the Volga Automobile Plant have a similar design, they contain the following parts:

- A circuit board that carries all the components of the unit;
- Relays – devices for turning on and off electrical appliances and devices;
- Fuses that prevent damage to devices and devices due to short circuits, voltage drops, etc.;
- Electrical connectors for integration of the unit into the electrical system of the car;
- Unit body.

The key details need to be said in more detail.

There are two types of boards:

- Fiberglass with printed assembly of components (on early models);
- Plastic with quick mounting of components on special pads (modern models).

Usually, boards are made universal, one board can be included in blocks of various models and modifications. Therefore, there may be unoccupied electrical connectors for relays and fuses in the assembled unit on the board.

There are also two main types of relays:

- Conventional electromagnetic relays for switching electrical circuits – they close the circuit by a signal from controls, various sensors, etc.;
- Timer relays and breakers for switching on and operating various devices, in particular, turn signals, windshield wipers and others.

All relays, regardless of their type, are mounted with special connectors, they are quick-change, so they can be replaced literally in a matter of seconds.

Finally, there are also two types of fuses:

- Cylindrical ceramic or plastic fuses with fuse insert, installed in connectors with spring-loaded contacts. Such parts were used in the early assembly blocks of VAZ-2104 – 2109 vehicles;
- Fuses with knife-type contacts. Such fuses are quick to install and are safer than conventional cylindrical fuses (since the risk of touching the contacts and the fuse insert is minimized when replacing the fuse). This is a modern type of fuse used in all current models of mounting blocks.

The bodies of the blocks are made of plastic, must have a cover with latches or self-tapping screws and fastening elements on the car. In some types of products, plastic tweezers are additionally present to replace fuses, they are stored inside the unit and insured against loss. On the outer surface of the blocks, all electrical connectors necessary for connection to electrical circuits are made.


Models and Applicability of Current Installation Units

It should be noted right away that in VAZ cars, a single mounting block was first installed on the 2104 model, before that separate blocks were used for fuses and relay installation. Currently, there is a wide variety of models and modifications of these components:

- 152.3722 – Used in models 2105 and 2107
- 15.3722/154.3722 – used in models 2104, 2105 and 2107;
- 17.3722/173.3722 – used in models 2108, 2109 and 21099;
- 2105-3722010-02 and 2105-3722010-08 - used in models 21054 and 21074;
- 2110 – used in models 2110, 2111 and 2112
- 2114-3722010-60 - Used in models 2108, 2109, and 2115
- 2114-3722010-40 - Used in models 2113, 2114 and 2115
- 2170 – used in models 170 and 21703 (Lada Priora);
- 21723 "Lux" (or DELRHI 15493150) – used in model 21723 (Lada Priora hatchback);
- 11183 – Used in models 11173, 11183 and 11193
- 2123 - Used in the 2123
- 367.3722/36.3722 – used in models 2108, 2115;
- 53.3722 – used in models 1118, 2170 and 2190 (Lada Granta).

You can find many other blocks, which are usually modifications of said models.

In current Lada models with air conditioners, there may be additional mounting blocks containing several relays and fuses for the air conditioning circuits.

Units from two main manufacturers are supplied to VAZ conveyors and to the market: AVAR (Avtoelectroarmatura OJSC, Pskov, Russia) and TOCHMASH-AUTO LLC (Vladimir, Russia).


A general view of maintenance and elimination of breakdowns in units

The mounting blocks themselves are maintenance-free, but this is the first module to be checked when any fault in the vehicle's electrical circuits occurs. The fact is that most often the breakdown is associated with the relay or fuse, or with the loss of contact in the connector, so it is possible to eliminate the problem by inspecting the module.

It is not difficult to find a mounting block in VAZs of different families, it can have different locations:

- Engine compartment (in models 2104, 2105 and 2107);
- Interior, under the dashboard (in models 2110 – 2112, as well as in current Lada models);
- Niche between the engine compartment and the windshield (in models 2108, 2109, 21099, 2113 – 2115).

To access the components of the unit, you need to remove its cover and perform diagnostics. The procedure for troubleshooting is described in the manual for operation, maintenance and repair of the car.

When buying new components or entire units, you should take into account their model and compatibility with certain car models. Usually, several types of blocks are suitable for one car model, so for some cars, the choice can be solved quickly and at low cost. With relays and fuses, things are even simpler, as they are standardized and versatile.

Post time: Dec-18-2023