Hall sensor VAZ 2107: what is it for and how does it work, identifying a malfunction and replacing an element

Many owners of a VAZ 2107 with a contactless ignition system are interested in the question of how to check the Hall sensor. The question, in fact, is quite relevant, since if the device fails, starting the engine becomes problematic or even impossible. Therefore, it is important to know what steps to take to correct the problem and how the sensor is replaced.

Hall sensor on the VAZ 2107

The Hall sensor is one of the main devices in the non-contact ignition system of gasoline engines. If there is a problem with this part, the operation of the engine is disrupted. In order to be able to diagnose the problem in a timely manner, it is important to know and understand how the Hall sensor (DH) works and, in particular, on the VAZ 2107, how to determine the malfunction and replace the device. All these points are worth dwelling on in more detail.

The Hall sensor is the main element of the non-contact ignition system of a gasoline engine.

Sensor purpose

A number of electronic systems of cars are equipped with sensors that send a signal to the appropriate unit responsible for the operation of the power unit about changes in certain parameters. The contactless ignition system of the VAZ 2107 also has such a device called a Hall sensor (DH). Its purpose is to determine the angle of position of the crankshaft and camshaft of the power unit. The sensor is installed not only on modern, but also on old cars, for example, VAZ 2108/09. According to the readings of the element, current is supplied to the spark plugs.

The principle of operation of the device

The work of DC is based on the effect of increasing the voltage in the cross section of the conductor, which is placed in a magnetic field. At the moment when a spark should appear, there is a change in the electromotive force, a signal from the distributor is sent to the switch and spark plugs. If we consider the Hall sensor, which is used today in ignition systems without the use of contacts, then it is a device for capturing changes in the magnetic field during camshaft operation. For the element to operate, a certain value of magnetic induction is required.

The sensor works as follows: there is a special crown-type plate on the distributor axis. Its feature is slots, the number of which corresponds to the number of engine cylinders. The sensor design also includes a permanent magnet. As soon as the ignition distributor shaft starts to rotate, the driven plate intersects with the sensor space, which leads to a pulse that is transmitted to the ignition coil. This impulse is converted and causes the formation of a spark on the candles, as a result of which the air-fuel mixture is ignited.

The principle of operation of the Hall element: 1 - magnet; 2 - a plate of semiconductor material

As the engine speed increases, the frequency of pulses coming from the DC increases, which determines the normal operation of the power unit. Despite the fact that the considered phenomenon was discovered long before the moment when mass-produced cars appeared, nevertheless it is used in automotive production today. The sensor is a fairly reliable device, the breakdown of which does not occur so often.

Video: Hall sensor operation

HOW HALL SENSOR WORKS [Ham Radio TV 84]

There are three contacts on the Hall sensor:

• weight;
• plus power supply (about 6 V);
• communication with the ignition switch.

Where is the DH on the VAZ 2107

If you are the owner of the VAZ "seven" with contactless ignition, then it will not be out of place to know where the Hall sensor is located. Finding the ignition distributor is not difficult, but the sensor itself is under its cover. To access the DH, you need to remove two latches and remove the cover of the distributor, after which you can see the sensor itself.

The Hall sensor on the VAZ 2107 is located in the engine compartment under the cover of the distributor

Wiring diagram

The Hall sensor has a direct connection with the switch and is connected according to the diagram shown in the figure.

The Hall sensor has a simple connection scheme: the signal from the device is fed to the switch, and then to the ignition coil

The switch itself performs the following functions:

• amplifies pulses up to 12 V and transmits them to the ignition coil;
• receives a signal from the DC in the form of an impulse.

In simple words, the switch is a conventional amplifier, which is made by analogy with the field-effect transistor assembly. Despite the simplicity of the circuit, the device is easier to purchase than to make yourself. The main thing is that the Hall sensor and the switch on the VAZ 2107 are correctly installed and connected. Otherwise, the sensor will not work properly.

The switch is designed to amplify the pulses coming to it from the Hall sensor

Signs of a malfunction of the Hall sensor on the VAZ 2107

The Hall sensor, like any other element of the car, can fail over time. However, even drivers with experience cannot always determine that the problem that has arisen is related to the device in question, since the malfunction can manifest itself in different ways. For diagnostics, it is often necessary to check for possible signs of a sensor failure before it is possible to find out that this particular sensor is the “culprit”.

At the same time, there are main symptoms by which it can be determined that not everything is in order with the DH on the VAZ 2107. Consider them:

• the engine does not start or the start is difficult;
• there are interruptions or jerks in the operation of the power unit at idle;
• the engine stalls while the vehicle is moving;
• twitching occurs when driving at high speeds.

If one of the listed signs appears, then the Hall sensor is recommended to be checked and, if necessary, replaced. Owners of cars with a contactless ignition system will not be out of place to carry a serviceable element with them as a spare part.

How to check the sensor

To find out the status of the sensor, it is necessary to perform an element check. This can be done in several ways. Consider them:

1. The easiest option is to install a known-good device, which you can take, for example, from a friend in the garage. If during the check the problem disappears and the engine starts to work without interruption, then you will have to go to the store to buy a new sensor.
   

   A simple way to check the DH on the VAZ 2107 is to install a known-good item that you can borrow from a friend in the garage
2. Diagnostics with a multimeter. To do this, the device is set to the voltage measurement limit and a measurement is made at the output of the sensor. If it is working, then the readings of the multimeter should be in the range of 0,4–11 V.
3. You can simulate a sensor. The procedure is simple: we take out the DH connector from the distributor, turn the key in the ignition switch to the “ignition” position and connect the 3rd and 6th outputs of the switch to each other. You can use a series-connected LED and a 1 kΩ resistor, which are connected in the same way. When a spark appears, this will indicate that the device under test has worked.
   

   One of the options for checking the Hall sensor is imitation of the device

Video: checking the sensor with a multimeter

Checking the Hall sensor on the VAZ 2107 can be performed without the device. In this case, the sequence of actions will be as follows:

1. We unscrew the spark plug on one of the cylinders or use a spare one and connect it to the high-voltage wire from the ignition coil.
2. We connect the thread of the candle to the mass of the body.
3. We remove the sensor, connect the connector from the switch and turn on the ignition.
4. We carry out a metal object, for example, a screwdriver near the sensor. If a spark appears on the candle, then the device under test is working.

Replacing the Hall sensor on the VAZ 2107

The process of replacing the DX is not the most pleasant, since you will have to not only remove, but also completely disassemble the ignition distributor. First you need to purchase the sensor itself and prepare the following tools:

• key for 13 (open-end or box);
• screwdriver;
• pliers;
• a hammer.

Before proceeding with the disassembly of the distributor, you need to pay attention to how it is located. It is best to make marks on its body and cylinder block. If adjusting the ignition is not a difficult task for you, then the distributor can be dismantled without any marks. The procedure for removing and replacing the sensor on the "seven" is carried out in the following sequence:

1. We remove the negative terminal from the battery, the cover from the ignition distributor, the vacuum hose and disconnect the connector that goes to the sensor.
   

   To get to the Hall sensor, you need to remove the distributor cap
2. To remove the distributor, unscrew the bolt by 13, remove the washer and take out the distributor itself.
   

   The distributor is fastened with a 13 bolt, unscrew it and remove the distributor
3. To disassemble the ignition distributor, it is necessary to knock out the pin that holds the shaft. To do this, we use a fitting of a suitable size, and for convenience we clamp the distributor in a vise.
   

   To remove the distributor shaft, you need to knock out the pin with a suitable tip
4. We remove the plastic stopper and take out the shaft.
   

   To dismantle the axis of the ignition distributor, you will need to remove the plastic stopper
5. We unscrew the two screws of the Hall sensor and the two screws of the sensor connector.
   

   To remove the Hall sensor, unscrew the sensor itself and the connector
6. We unscrew the fastening of the vacuum corrector and take out the sensor through the hole.
   

   After removing the vacuum corrector, remove the sensor through the hole
7. We install a new sensor and assemble in the reverse order.

After dismantling and disassembling the distributor, it is recommended to clean the shaft from soot, for example, by washing it in diesel fuel. As for the repair of the sensor, this element is considered non-repairable and if it fails, only replacement is necessary. In addition, its cost is not so high, within 200 r.

Video: how to replace the Hall sensor on cars of the VAZ family

Replacing the Hall sensor VAZ classic, NIVA

If there are malfunctions in the car's ignition system associated with the Hall sensor, it is not necessary to contact the service to eliminate them. You can diagnose a malfunction on your own, even in the absence of special devices. The main thing is to get acquainted with simple and understandable recommendations and strictly follow them.