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Hall sensor VAZ 2109 carburetor causes of malfunction. Final inspection of households

VAZ 2109 cars equipped with carburetor engines have a contactless ignition system with a Hall sensor. The main task of the VAZ 2109 Hall sensor is to supply control pulses to the switch, which converts the received pulses and directs them to the primary winding of the ignition coil.

This microelectronic sensor is located in the housing of the ignition distributor sensor under the dust shield. Depending on the type of distributor, it is secured to the base plate using 2 screws or rivets. The operation of replacing the Hall sensor of a VAZ 2109 is not difficult. The replacement can be done within half an hour by any car enthusiast without the help of specialists.

Sensor check

It is not always the case that if the Hall sensor malfunctions, the car’s power unit does not start. There may be problems with ignition, such as interruptions in engine operation in any mode, absent or unstable idling, as well as loss of power. There are two ways to check the Hall sensor. The first is suitable for those who do not have special knowledge in the field of auto electrics and electronics.

With this method, you need to purchase a new and known-good sensor from an auto parts store and install it correctly in place of the old one. If the engine starts after this operation, then the problem is solved. If not, then the problem is in the resistor, switch, coil, ignition switch, wires, spark plugs or other parts of the distributor.

The second method of checking the VAZ 2109 Hall sensor requires special knowledge in electrical engineering. In addition, to carry out self-diagnosis, you must prepare the following instruments and devices:

a voltmeter or multimeter with a measurement limit of at least 15 V and an internal resistance of at least 100 kOhm;
3-pin block from the distributor with low-voltage wires;
resistor with a resistance of 2 ohms.

The check must be carried out as follows.

First you need to remove the distributor from the car.
Then you need to connect a block with wires, a resistor and a voltmeter to the connector of the low-voltage wires according to a certain circuit.
After this, you need to apply voltage from the battery (9-14 V) to the positive contact and slowly turn the distributor shaft.
During this operation, you need to record the minimum and maximum voltmeter readings.

Normally, the minimum voltage should be less than or equal to 0.4 V, and the maximum should not differ from the voltage supplied from the battery by more than 3 V. If, when turning the distributor shaft, there is no sharp voltage jump or the minimum and maximum values differ from the norm , this means that the sensor is broken and should be replaced.

Replacing the device

Replacing the Hall sensor

In order to replace the Hall sensor, you first need to remove the distributor from the drive of the auxiliary units. The dismantling algorithm is as follows.

First of all, you need to disconnect the terminals from the battery.
Then you need to remove the armored wire from the cover of the breaker-distributor and unhook the hose from the vacuum corrector.
Then you need to remove the throttle cable from the holder so that it does not interfere, unscrew the nut securing the bracket on which the wires are held, remove the bracket from the stud and move it to the side.
Next, you need to scratch with a screwdriver or draw a straight line with a marker, passing from the distributor body to the drive housing of the auxiliary units. This mark will allow you to maintain the same ignition timing during installation of the distributor.
After this, you need to unhook the block with wiring from the breaker-distributor.
Then you need to remove the dirt plug from the clutch housing hatch and use a screwdriver to turn the flywheel until the piston of the first cylinder is in the top position.
Now you need to unscrew the 2 remaining nuts and remove the distributor.

After dismantling the unit, you can begin replacing the sensor; to do this, you need to follow a sequence of actions.

Unscrew the screws and remove the distributor cover.
Pull the slider up and remove it, then remove the dust shield.
Remove the low-voltage wire connector by unscrewing the screw.
Unscrew the screws securing the support plate and remove the ring from its pin.
Unscrew the screws of the vacuum corrector, remove its rod from the plate pin and remove it from the body.
Lift the plate with a screwdriver and also pull it out of the case.
Unscrew the screws securing the sensor and replace it with a new one.

If the sensor is attached to the plate with rivets, then they need to be replaced as an assembly. Installation of the device should be carried out in reverse order. Before installing the distributor, you need to turn the outer contact of the slider to the terminal of the first cylinder.

An electromagnetic device called a Hall sensor (hereinafter referred to as Hall sensor) is used in many devices and mechanisms. But its greatest application was found in the automotive industry. In almost all models of the domestic automobile industry (VAZ 2106, 2107, 2108, etc.), the non-contact ignition system for a gasoline engine is controlled by this sensor. Accordingly, when it fails, serious problems arise with the operation of the engine. In order not to make mistakes when diagnosing, it is necessary to understand the principle of operation of the sensor, know its design and testing methods.

Briefly about the principle of operation

The principle of operation of the ignition sensor is based on the Hall effect, which received its name in honor of the American physicist who discovered this phenomenon in 1879. By applying a constant voltage to the edges of a rectangular plate (A and B in Fig. 1) and placing it in a magnetic field, Edwin Hall discovered a potential difference at the other two edges (C and D).

Fig.1. Demonstration of the Hall effect

In accordance with the laws of electrodynamics, the Lorentz force acts on charge carriers, which leads to a potential difference. The value of the hall voltage U is quite small, ranging from 10 µV to 100 mV, it depends on both the current strength and the electromagnetic field strength.

Until the middle of the last century, the discovery did not find serious technical application until the production of semiconductor elements based on silicon, ultra-pure germanium, indium arsenide, etc., with the necessary properties, was established. This has opened up opportunities for the production of small-sized sensors that can measure both field strength and current flowing through a conductor.

Types and scope of application

Despite the variety of elements that use the Hall effect, they can be divided into two types:

It should be noted that the digital type includes the following subtypes:

unipolar - triggering occurs at a certain field strength, and after it decreases, the sensor returns to its original state;
bipolar - this type reacts to the polarity of the magnetic field, that is, one pole turns the device on, and the opposite pole turns it off.

Typically, most sensors are a component with three terminals, two of which are supplied with bi- or single-pole power, and the third is a signal.

Example of using an analog element

Let us consider, as an example, the design of a current sensor whose operation is based on the Hall effect.

Simplified circuit of a current sensor based on the Hall effect

Designations:

A is a conductor.
B – open magnetic conductor ring.
C – analog Hall sensor.
D – signal amplifier.

The operating principle of such a device is quite simple: the current passing through the conductor creates an electromagnetic field, the sensor measures its magnitude and polarity and produces a proportional voltage U DT, which is supplied to the amplifier and then to the indicator.

Purpose of DC in the car ignition system

Having understood the principle of operation of the Hall element, let's consider how this sensor is used in the contactless ignition system of the VAZ line of cars. To do this, let's look at Figure 5.

Rice. 5. Principle of the SBZ device

Designations:

A – sensor.
B – magnet.
C – plate made of magnetically conductive material (the number of protrusions corresponds to the number of cylinders).

The operating algorithm of such a scheme is as follows:

When the chopper-distributor shaft rotates (moving synchronously with the crankshaft), one of the protrusions of the magnetically conductive plate takes a position between the sensor and the magnet.
As a result of this action, the magnetic field strength changes, which causes the DC to operate. It sends an electrical impulse to the switch that controls the ignition coil.
The voltage required to form a spark is generated in the Coil.

It would seem nothing complicated, but the spark must appear at a certain moment. If it forms earlier or later, it will cause a malfunction of the engine, even stopping it completely.

Manifestation of malfunction and possible causes

Irregularities in the operation of household farms can be detected by the following indirect signs:

There is a sharp increase in fuel consumption. This is due to the fact that the fuel-air mixture is injected more than once during one crankshaft rotation cycle.
Manifestation of unstable engine operation. The car may begin to “twitch” and a sharp deceleration occurs. In some cases, it is not possible to reach a speed of more than 50-60 km/h. The engine stalls during operation.
Sometimes the failure of the sensor can lead to the transmission being locked, without the ability to shift it (in some models of imported cars). To correct the situation, a restart of the engine is required. In case of regular such cases, one can confidently state that the DP has failed.
Often, a breakdown can manifest itself in the form of the disappearance of the ignition spark, which, accordingly, will make it impossible to start the engine.
The self-diagnosis system may experience regular failures, for example, the check engine light will come on when it is idling, and the light will go out when the speed increases.

It is not at all necessary that the listed factors are caused by the failure of the DP. There is a high probability that the malfunction is caused by other reasons, namely:

ingress of debris or other foreign objects onto the DP housing;
the signal wire has broken;
water has entered the DP connector;
the signal wire is shorted to ground or the on-board network;
the shielding sheath on the entire harness or individual wires is torn;
damage to the wires supplying power to the DC;
the polarity of the voltage supplied to the sensor is reversed;
problems with the high-voltage circuit of the ignition system;
problems with the control unit;
the gap between the DC and the magnetic conductive plate is incorrectly set;
Perhaps the reason lies in the high amplitude of the end runout of the camshaft gear.

How to check the performance of the Hall sensor?

There are different ways to check the serviceability of the SBZ sensor; we will briefly talk about them:

We simulate the presence of DH. This is the easiest way to quickly check. But its effectiveness can only be discussed if a spark does not form when there is power at the main components of the system. To test, follow these steps:

disconnect the three-wire plug from the distributor;
we start the ignition system and at the same time “short” the wire with ground and the signal from the sensor (pins 3 and 2, respectively). If there is a spark on the ignition coil, it can be stated that the SBZ sensor has lost its functionality and needs to be replaced.

Please note that in order to detect sparking, the high-voltage wiring must be close to ground.

Using a multimeter to check. This is the most well-known method, and is given in the car manual. You need to connect the probes of the device, as shown in Figure 7, and measure the voltage.

On a working sensor, the voltage will fluctuate in the range from 0.4 to 11 volts (remember to set the multimeter to DC measurement mode). It should be noted that checking with an oscilloscope will be much more effective. It is connected in the same way as a multimeter. An example of an oscillogram of a working DC is shown below.

Installation of a known working HH. If there is another sensor of the same type available, or it is possible to borrow it for a while, then this option also has a place to exist, especially if the first two are difficult to do.

There is another verification option, which is similar in principle to the second method. It can be useful if you don't have measuring instruments at hand. For testing, you will need a 1.0 kOhm resistor, an LED, for example, from a lighter flashlight, and several wires. From this entire set we assemble the device in accordance with Figure 9.

Rice. 9. LED tester for checking DH

We carry out testing according to the following algorithm:

Check the power supply to the sensor. For this purpose, we connect (observing polarity) our tester to terminals 1 and 3 of the DC. Turn on the ignition, if everything is normal with the power supply, the LED will light up, otherwise you will need to check the power circuit (after making sure that the LED is connected correctly).
Let's check the sensor itself. To do this, we “transfer” the wire from the first terminal to the second (signal from the DC). After this, we begin to turn the camshaft (by hand or with a starter). The blinking of the LED will indicate the serviceability of the DC. Otherwise, just in case, we check that the polarity is correct when connecting the LED, and if it is done correctly, we replace the sensor with a new one.

The use of a Hall sensor in the ignition system of a VAZ 2109 car has become a landmark event in the domestic automotive industry. Of course, instead of the previously used contact ignition, a contactless one has been installed. A huge advantage of contactless ignition is a stronger spark and, as a result, better combustion of the combustible mixture and an increase in engine power.

However, like any device, the Hall sensor can fail. VAZ 2109 does not start with a faulty hall sensor. The Hall sensor is designed so that the switch sees at what frequency the engine rotates and determines the correct moment of supplying a spark to the spark plug. The Hall sensor is a magnet and a receiver (Hall element) in the gap between which the ignition distributor drum rotates. The ignition distributor drum looks like this:

Drum with slots for Hall sensor

When there is emptiness in the gap between the magnet and the Hall element, the voltage at the output of the Hall sensor drops. When the metal part of the drum is in the gap, the voltage at the output of the Hall sensor increases to a level of about 3 Volts. Therefore, when the engine is running and the ignition distributor drum rotates along with the engine camshaft, the Hall sensor transmits either 0.4 Volts, then 3 Volts, then 0.4 Volts or 3 Volts to the switch.

Hall sensor gap

The switch deciphers these impulses and knows when to charge the ignition coil so that a spark is formed at the desired engine stroke.

What if there is a need to check whether the Hall sensor is working properly. There is only one symptom of a malfunction of the Hall sensor of the VAZ 2109 - the car does not start, or stalls for no reason. You just need to remove the ignition distributor and assemble the following circuit. Rotate the distributor shaft and look at the voltage with a voltmeter.

Hall sensor check

To home

vaz2109.net

How to check the Hall sensor on a VAZ-2109 (injector, carburetor)

The Hall sensor operates on the principle of an analog converter that switches power in the car's ignition system.

The Hall effect is versatile and has several obvious advantages that explain its use in the automotive industry:

sensors allow you to increase the performance of a car engine;
safety during movement increases.

In the VAZ-2109 and some other models of the domestic automobile industry, the non-contact Hall sensor responds to changes in the magnetic field, accordingly changing the supply voltage in the ignition system, and determines the moment of sparking.

Read also: How to remove the VAZ-2109 box yourself (carburetor, injector)

The principle of operation of the Hall sensor is based on the use of a semiconductor crystal that reacts to positively and negatively charged particles when passing a magnetic field. Speaking about sensors installed in cars, it is worth noting that their malfunction can lead to blocking the operation of the injector, as a result of which the engine will stall after starting or not start at all when the ignition key is turned. By the way, this symptom is one of the reasons to check the Hall sensor installed on your car.

Read also: Self-replacement of the VAZ-2109 thermostat

You can learn how to check the Hall sensor on a VAZ-2109 from numerous video instructions published on the Internet. Most sensor models, including those used on Russian-made cars, are checked with a multimeter. The options are:

switch the multimeter to voltmeter mode and connect it to the output contact of our sensor;
put a working sensor in place of the “suspect” and analyze the changes;
replace the sensor with a device with similar properties.

When planning a test, it is worth considering that getting to the Hall sensor itself is not so easy. Its suitability can be determined without removing it from its location. To do this, you need to take two pins and pierce the insulation of the black-and-white and green wires in the connecting block with them. Then you need to connect the contacts of the multimeter to the pins and turn the ignition key. While turning the flywheel slot in the hatch on the clutch housing with a screwdriver, you should simultaneously observe the readings of the multimeter.

Initially the reading will be 0.4 volts, and as the flywheel is turned it will first drop to almost zero and then rise. The limit that indicates your vehicle's Hall sensor can be considered suitable is up to 12 volts. In this case, the malfunction that causes the car to stall should be looked for somewhere else. Perhaps the problems are related to the injector or carburetor, the fuel supply system, or damage to the electrical wiring.

It is important to remember that it is necessary to disconnect the block with wires from the sensor only when the ignition is turned off, otherwise it may fail. In addition, if there are no means of measuring voltage, you can replace the sensor being tested with a known-good one, but this is a more labor-intensive process that requires disassembling the distributor (if the car is equipped with a carburetor).

To summarize, it should be noted that checking the Hall sensor is one of the effective means of analyzing possible vehicle malfunctions, and due to its relative simplicity, it can be one of the first steps when troubleshooting. If the sensor is working properly, it is possible that the problems are more serious and global, requiring the replacement of complex and expensive equipment.

ladaautos.ru

Checking the hall sensor

If your car has a contactless ignition system, it needs to be checked and diagnosed periodically. This system consists of a distributor, a coil and a switch, and a hall sensor. All these parts must be checked separately, but today let's diagnose the hall sensor. This can be done in two ways using a voltmeter and a 2 kOhm resistance, or using devices such as AZ-1 and MD-1.

Let's start with the second method. You need to connect MD-1 to the switch connectors, then turn on the ignition, but do not start the engine. If the P indicator lights up on the device, this indicates that the ignition switch and relay are working properly. If the letter K is displayed, then only the ignition coil is working. Turn on the starter and look at the indicator again. If we see the letter D flashing on it, then you can rest assured that the hall sensor is absolutely working. What if the letter D is not displayed? Then we connect A3-1 instead of the hall sensor; this device performs the functions of a sensor. If you connect it, you can even drive a car. True, at a speed of no more than 90 km/h. If the corresponding signal is displayed on this device, this directly indicates that the hall sensor needs to be replaced. If there is no signal, you need to check the wiring.

But what if you don’t have these devices at hand? Then we move on to the first method, using a voltmeter and a resistor. The ignition distributor must be removed and a voltmeter and resistance connected to it. Then we apply a voltage of 10-12V. We set the device to a minimum measurement of 15V, while the internal resistance should be no less than 100 kOhm. It is with these settings that the voltmeter can give accurate readings. Then we carefully turn the camshaft, and the device should show how the voltage jumps sharply from minimum to maximum. In this case, the lowest voltage should be no more than 0.4V, and the highest, different from the applied voltage, should be 3V more.

But what if you don’t even have a voltmeter at hand? There is a third method - although it is old-fashioned, it is a proven method - checking the hall sensor using spark plugs. Having unscrewed any spark plug, place it on the engine, turn on the ignition and immediately see whether there is voltage at both contacts of the ignition coil. The next step is to pull out the wire located in the middle from the distributor cover. Then it needs to be inserted between the brake cylinder tubes so that the exposed section of the wire is five to ten centimeters from the cylinder shell. Then, using a small piece of wire, connect one end to the negative terminal of the battery, the other to the central contact of the distributor. If a spark jumps between the wire and the cylinder shell, then the hall sensor needs to be replaced. The check, of course, must be performed with the ignition on.

If the hall sensor is faulty, we go to a car store, buy a new one and install it ourselves. Having connected the wires to the connector, turn on the ignition. Then we draw a metal plate along its gap. If there is a spark, then everything is in order.

Why is the hall sensor called that way? It got its name due to the Hall effect, when a transverse potential difference arises in a semiconductor under the influence of a magnetic field. The sensor itself is a semiconductor connected to a permanent magnet, between which there is a steel cylindrical screen.

Learn more about what electronic contactless ignition is in the video.

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vazikov.ru

12.7.8 Checking the Hall sensor

Service and operation

Manuals ￫ VAZ ￫ 2109 (Lada Samara)

Contact numbers of the control unit connection block

EXECUTION ORDER

1. Disconnect the central high voltage wire from the ignition distributor and connect it to ground.
2. Disconnect the connection block.
3. Connect a voltmeter to the extreme contacts “1” and “3”, turn on the ignition. The voltmeter should show a voltage of about 9 V. Otherwise, check the wiring.
4. Slide back the protective cover from the block, connect a voltmeter to contacts “1” and “2” and install the block into the socket on the ignition distributor.
5. Remove the distributor cap, slider and dust screen.
	6. Rotate the engine crankshaft so that the teeth of the distributor armature (1) do not overlap the Hall sensor (2). Turn on the ignition. The voltage should be 4 V.
7. Rotate the crankshaft so that one of the armature teeth aligns with the Hall sensor. The voltage should drop to 0–0.5 V. Turn off the ignition. If the voltage differs from the specified value, replace the Hall sensor.
	8. Connect the ohmmeter to contacts “1” and “4”, then to contacts “2” and “27” and finally to “3” and “25”. In all cases, the resistance should be zero. If the resistance is different from zero, then there is a break in the wiring.

Cars are constantly evolving, so the emergence of new devices is not a surprise. An example of the development of domestic automobile production was the appearance of a Hall sensor on carburetor versions of the VAZ 2109.

Functions and location

On carburetor VAZ 2109, the Hall sensor (HL) is responsible for opening and closing the contact group. When the screen with windows is rotated, a signal is sent to the device, which transforms into an electrical one. Through the switch, the signal goes to the ignition coil, and there it turns into an electric charge - a spark.

The DH is located at number nine on the ignition distributor. You need to look for the device under the dust shield. The sensor is secured to the base plate using rivets or a pair of screws. This already depends on the type of distributor used.

On injection VAZ 2109 there is no Hall sensor. Its functions are performed by the crankshaft position sensor.

Signs of breakdown

If the DC fails, the car itself will notify you of the presence of a malfunction. To determine problems with the diesel engine, there are certain signs coming from the engine:

You simply cannot start the engine;
There are interruptions in the operation of the power unit - the smooth running becomes not so smooth, jerks appear;
Idle speed is broken or completely absent;
The engine may suddenly turn off or stall;
Motor power is noticeably lost.

Before you run to the engine compartment and change the Hall sensor, first you need to make sure that it is the cause of all the troubles with the engine. Still, the signs are indirect, and they can be caused by a malfunction of other elements of your car.

Checking status

There are several main methods that are used today to check the current state of the Hall sensor. Let's get to know each of them in more detail, and you decide for yourself which one you will use the next time you check the DH on your VAZ 2109.

Verification method	Your actions
Replacing an old device with a new one	This is the simplest method, which will require you to have a spare Hall sensor on hand, of which you are confident that it will work. Simply remove the old sensor, insert the new one in its place and try to start the car. If everything works, you have found the reason. If not, you will have to look for the source of the problems in other systems.
Checking the output voltage	For this method, you will need a tester connected to the output of the device. If the Hall sensor is working properly, the tester will show values in the range of 0.4-11 Volts. If the data does not meet the established standards, the household will have to be replaced
Simulation of device operation	A popular method in which you deceive your own car by simulating the operation of the Hall sensor. You need to remove the plug block, turn on the ignition and connect outputs 3 and 6 together. If a spark starts to jump, you can be sure that your sensor has failed.
Checking without additional devices	Here you don't need a tester or voltmeter. First, connect the lead from the coil to the spark plug, and connect the thread of the spark plug to ground. Remove the carriage with the sensor and attach the connector. Now you can turn on the ignition. Using a screwdriver, move the tool near the device - the Hall sensor. If a spark appears on the spark plug, this indicates the serviceability of the DH. If not, the conclusion is obvious.

If you discover that the DC is faulty, you should definitely replace the device. We do not recommend delaying this event.

Replacement

There is nothing particularly difficult about replacing the DH on a domestic nine. Therefore, even a novice driver can take on the job with his own hands.

Disconnect the negative terminal from the battery.
Disconnect the armored wires from the distributor, disconnect the hose from the vacuum corrector.
Next, remove the gas cable and put it aside for now so as not to interfere with the process.
Unscrew the bracket fasteners that hold the wires. Remove the bracket from the stud and move it aside. Otherwise he will disturb you.
Be sure to draw a straight line on the auxiliary drive housing and distributor. This location will allow you to avoid disturbing the ignition timing during reassembly.
Disconnect the power supply with wires.
Remove the plugs from the clutch housing and turn the flywheel with a screwdriver so as to set the piston of the first cylinder to the top dead center position.
To remove the distributor, you need to unscrew two more mounting nuts holding the device.
Remove the cover from the distributor, remove the slider and pull it up. Only a little.
Remove the dust cover.
Now unscrew the mounting bolt to remove the plug.
We also need to unscrew the bolts that hold the plate of our desired sensor.
Remove the vacuum corrector mounting bolts, remove the retaining rings, corrector and rod.
To get the wires out, you will need to release the clamp there.
Remove the mounting plate and unscrew the mounting bolts, which will allow you to finally remove the failed Hall sensor.
It is now necessary to install a new sensor and assemble the unit, proceeding in the reverse order.

Hall sensors have become a real breakthrough in the field of mechanical engineering. Thanks to these devices, there was no need to use contact sensors, which were inaccurate, required constant adjustment, and did not last long. The VAZ 2109 Hall sensor is located on the distributor and controls the ignition system. If this is a VAZ 2109 injection engine, then there are several Hall sensors and they all have a separate role.

In addition to ignition systems, Hall sensors are used to read data from the crankshaft, camshaft, wheels and other rotating mechanisms. Reading occurs contactlessly, due to the magnetic Hall effect. When a metal object passes near the sensor, it immediately detects it; its principle is somewhat reminiscent of a metal detector.

You can't do without Hall sensors on cars that use an ABS system. Here such sensors are needed in order to read data on wheel speed. Checking and replacing the Hall sensor is not at all difficult; it is only important to understand how it works.

We are looking for a sensor for a VAZ 2109

If we are talking about a carburetor engine installed on earlier VAZ 2109 models, then here there is only one and it is located on the ignition distributor. In this case, the Hall sensor replaces the old contact group, which was mechanically opened and closed by the distributor shaft. Now this task is performed by a Hall sensor.

The switch passes the voltage through the sensor and records its changes when the roller rotates, that is, when you try to start the engine.

Otherwise, everything is exactly the same as with contact ignition, that is, the spark is supplied at the moment when the slider is opposite the spark plug contact. If the Hall sensor in the distributor on a VAZ 2109 stops working, a spark will not form, and therefore the engine will not start.

The switch also takes on the task of controlling the ignition angle; it does this automatically depending on engine speed.

Hall sensor check

To check the Hall sensor on a VAZ 2109, and the entire ignition system as a whole, you need to purchase several inexpensive devices. For example, there is a device called AZ-1 (emergency ignition). If the Hall sensor suddenly fails, this device can replace it, although the speed will be limited to 90 km/h.

AZ-1 is used when the car is idle for a long time, in rainy weather, or when the ignition system fails.

There is also a device called MD-1 (instant diagnostics). This device is connected instead of a switch and watch which lights light up. If the “P” LED lights up, it means the ignition switch and relay are working properly.

If the “K” LED lights up, then the ignition coil is in order, that is, its primary winding.

Well, the “D” LED should blink if you rotate the engine with the starter, this will indicate the serviceability of the Hall sensor.

Often the cause of a breakdown is not the Hall sensor, but the power wires, which are not so reliable on the VAZ 2109. High voltage and poor contact can cause carbon deposits to form in the socket of the coil and distributor. If it is not cleaned, the spark will become weaker, which will worsen engine performance. But it is recommended to carry an AZ-1 or a spare Hall sensor when driving your VAZ 2109 in any case.