The circuit shown in the previous chapter is powered from the main relay 6. It is also called the "ignition relay". There is also a fuse 1 in the circuit.
When the ignition circuit is broken, both the speedometer and the ECU module do not work on the VAZ-2112, and in general the engine does not start. So advice about checking the relay would look silly.
If you still decide to dismantle the sensor, connect a 1 kOhm resistor to its output (to the middle terminal). The resistor tap is connected to the positive power supply. By turning the shaft by hand, pulses can be observed at terminal 2. There are six pulses per revolution.
The diagram below shows exactly how the speed sensor works.
Items 1 and 2 are interchangeable.
To remove the sensor from the car, you must disconnect its connector. The sensor body is fixed near the CV joint - the required point is shown with an arrow.
When the connector is disconnected, take the flat key "22" and unscrew the plastic nut. Then you can change the sensor or repair it.
To replace the sensor drive, unscrew the M6 nut with a key "10" and take it out together with the washer. The drive housing is wiggled from side to side - a “14” spanner key is needed.
Installation requirements: on the one hand, it is necessary to obtain tightness, on the other, the plastic cannot be broken.
The tidy, as well as the speedometer on the VAZ-2112, may not work when they are disconnected from the "ground" or from the power supply. Be aware that the speedometer is powered separately from the instrument panel. This also applies to the "mass". Unsoldering:
Connector X2 is colored red, X1 is white. Terminals 8 and 9 in connector X2 are the output and input of the speedometer. The output is connected to the on-board computer.
Both terminals (X1-9 and X2-2) are connected to one wire - orange. This line is protected by a fuse installed in the main mounting block (F19).
In the second step, unscrew the two self-tapping screws holding the dashboard in place (photo 3). Further, the petal brackets are squeezed to remove the entire tidy.
Sometimes they do this: they make a tap from terminal 9, and, without turning on the gear, move (push) the car. In this case, the motor remains muted. Pulses will appear on the tap, which can be detected even by a voltmeter. The voltmeter itself must be a pointer.
The presence of pulses indicates a malfunction of the speedometer, and the absence - a sensor malfunction. However, power or ground may not be supplied to the speed sensor (see above).
Repairing a faulty speedometer will not work - it will be easier to replace it. But first you need to find out exactly what the problem was in him.
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If suddenly your electronic speedometer refused to work on your VAZ 2110 - 2112 car:
These are direct indicators of a malfunction of the electronic speedometer of the car. This problem is common and quite solvable.Most often, the main reasons for which a car speedometer fails are: a breakdown of the speed sensor, an open or short circuit in the electrical circuit wires, no contact in the plug of the speed sensor (DS), oiling or contamination of the sensor if it gets oil from the gearbox (gearbox) or contamination due to oil leakage through the engine valve cover, the speedometer drive gears located inside the gearbox have broken.
To fix the breakdown of the speedometer, you need to find the cause of its occurrence. The speedometer may not work due to a blown fuse F19 (10A) located in the fuse box. If the fuse is in order, then the first step is to check all the contacts and, if necessary, clean them from dirt. Oxidation of electrical circuit contacts is the smallest breakdown. However, it is precisely because of the oxidized contacts that the speedometer needle can jump or fall to zero.
If the wires of the speed sensor are frayed and broken, the speedometer needle falls or jumps when you start the engine. The speed sensor in the 2110 is in close proximity to the exhaust manifold. It is when the wires come into contact with the collector that the wires melt, the wires break and short. To locate the break, it is necessary to ring the wires with a tester and insulate them.
The next reason for the inoperative speedometer is the failure of the idle sensor itself. The sensor is based on the Hall effect. The speed sensor sends an electrical impulse to the vehicle engine controller with a frequency proportional to the current speed of the vehicle's driving wheels. Through the wires of the electric circuit, the generated current flows to the car's speedometer and makes the electric motor rotate inside it, deflecting the speedometer needle. On VAZ 2110-12 cars with an eight-valve engine, the speed sensor is located next to the oil level dipstick in the gearbox. To dismantle the sensor, it is necessary to remove the plug by pressing on the latch. The sensor should be easy to unscrew. If the sensor is tightly wrapped, unscrew it using a 22 key. To make sure that the speedometer breakage is detected correctly, use a new or known working speed sensor. The reason for the breakdown of the speed sensor may be not the tightness of the case and the ingress of moisture and dirt. You can check the performance of the new speed sensor while driving or hanging the front wheels.
To check the speed sensor drive, remove the sensor, wrap your fingers around the sensor drive, or insert a stick 5 centimeters long into it and push the car a little back and forth. If an uneven rotation of the shaft is felt during the rotation of the wheels, it is likely that the teeth of the gear of the drive of the speed sensor are damaged or the gear is not installed. Remove the gear and inspect it. Replace the gear if the teeth of the gear or its drive are chipped or deformed. After eliminating the malfunction, start the engine and when the car is moving at a speed of 30..50 km / h, check the operation of the speedometer.
To check the dashboard malfunction, we recommend replacing it with a known working one from another car. Spare parts are no longer supplied to the VAZ 2110-2112 dashboards, so motorists have to buy new dashboards in stores or used dashboards at auto dismantling stations in the city.
After purchasing the dashboard, you need to correct the vehicle mileage on the speedometer. To adjust the mileage (winding or wrapping), call us, and our experts will help you bring the speedometer readings in line with the real mileage of your car. We are correcting the mileage on domestic cars VAZ 2110, VAZ 2115, Kalina, Priora, Largus, GAZ-3110 Volga, UAZ Hunter, UAZ Patriot, UAZ Simbir in Kirov.
Call us on the phone +7-922-900-70-60 and we will answer all your questions.
Technical characteristics of the VAZ 210-12 speed sensor:
The speedometer does not work on the VAZ 2112 for reasons that are more complex. Mechanics remember that after the vehicle was updated, the mileage counter, as well as the speedometer, were replaced with electronic ones. They work differently. The point is in reading and further sending information by the speed detection sensor located in the gearbox to the dashboard.
It becomes clear that the probable breakdown should be looked for in this area. But not without nuances. AvtoVAZ does not produce components for the instrument panel. This means you have to look for a brand new panel. It will be expensive, but there is an option to save money. You need to go to the dismantling, where they are engaged in such cars.
On the tidy, the incorrect operation of the speedometer can be shown in different ways. It happens that the arrow stays in one place, as if the power unit is not started. But it can also happen that the speed is shown to be too high. The most likely cause of the breakdown is considered to be problems with contacts - they oxidize. Visually, it is very easy to define such a problem, because the oxide is striking. As a repair, you just need to clean them with high quality and return them to their original place.
When the contacts are in complete order, it is worth finding out if the voltage is supplied directly to the sensor. Here you have to use a tester. If it is not there, then take a classic lamp with a pair of wires adjacent to it.
It may also be due to the deterioration of the wire directed to the sensor itself. This can not always be seen by external inspection, because there is an electrical tape on the outside, but the internal fats are torn apart.
It is worth recalling that from each sensor to the tidy, the wires go directly through the assembly block. This means that the case may be in him. Considering that the vast majority of motorists are not very well versed in electrics, you need to think about going to a service station. Well, when electricity does not go to the contacts, the conclusion is quite logical - to replace the speed sensor.
There is absolutely nothing difficult about this. Moreover, there is no need to have specialized knowledge and skills. You only need a twenty-second diameter wrench. For reliability, it is worth stocking up with a 10 key. Even a pit is not needed, because you can get to the sensor from under the hood.
You should always remember about safety rules.Work must not be started if the negative terminal has not been removed from the battery. When disconnected, remove the connector directly from the sensor itself. Using the prepared key for twenty-two, dismantle it.
To all of the above, it must be added that the speedometer may stop functioning due to a broken rod. In such a situation, it may not be necessary to remove the drive of the speedometer itself. That's when the “tenth” key will be needed, but anyway, extract it with the utmost care. There is a risk of dropping it into the gearbox pan. Then things will be much worse. The worst thing that can happen is that the stem gets stuck between the gears. Naturally, this will simply disable the transmission for a long period of time.
When returning the actuator rod to its place, be sure to grease the ring used as a seal. It remains only to connect all the wires and check if the speedometer is working. If so, then it is very clear why the speedometer does not work on the VAZ 2112. Well, if not, it’s better to go to a good master.
In a situation where the speedometer installed on the VAZ-2110 injector does not work normally, the person driving puts at risk both their own health and the lives of passengers. At the same time, he can easily "earn" a fine from a traffic police officer for too high a speed. Thus, a serviceable speedometer avoids a lot of trouble.
The main symptoms of a malfunction of this device are as follows:
the arrow remains in place, despite the fact that the car is moving;
when driving, it hesitates or freezes;
the device functions normally with an unheated power plant, but later the arrow stops moving.
If the above signs are found, it is necessary to deal with the breakdown as soon as possible and fix it.
So, oxidation of contacts is considered a fairly easy-to-fix malfunction. It is characteristic of it "jumping" of the arrow, in spite of the fact that the speed of movement remains stable. The elimination of the problem occurs by cleaning the contacts.
The wires are frayed. This reason can be suspected by the chaotic movement of the arrow when starting the engine. Meanwhile, experts note that sometimes the problem does not manifest itself for a long time. It is possible to identify it with a tester.
Broken sensor. The speed control device, the operability of which is questioned, is replaced with a knowingly serviceable one. If the speedometer after this procedure began to function normally, then there is no point in looking for a breakdown further. Often, sensors become unusable after their case collapses, water or dirt gets inside.
Connectors. They are in the VAZ-2110 in a place where dirt constantly gets on them. As a result, the contact is broken and the speedometer needle moves chaotically. The connectors must be completely cleaned and the connection checked.
Often, the speedometer also starts to malfunction due to shaft wear. In this situation, it will be possible to get rid of the problem only after the complete replacement of the above-mentioned part.
As you know, the manufacturer installs an electronic speedometer on this model. If it is he who has fallen into disrepair, then this problem is quite serious, since the above device is not sold by itself. For this reason, you will have to buy a whole shield.However, in fact, nine out of ten cases, the problem is in a completely different place.
On a VAZ-2110 with an 8-valve engine, the speedometer receives information from the speed sensor. It, in turn, is located in the gearbox. There, by means of two gears, it receives data on the torque from the gearbox shaft.
Similarly, everything works for cars with 16-valve engines.
It is worth recalling that it will be more convenient to access it directly through the gearbox, since it is very inconvenient to do this from below.
Another very common reason is power grid problems. It all needs to be checked. In addition, attention is also paid to:
reliable fastening of wiring in the terminals;
their general condition;
fuses located within the mounting block.
In a situation where no damage to the electrical network is found, you will have to take on the sensor itself. Its breakdown is the third most common cause of speedometer failure. Checking it is done in the following sequence:
the sensor is removed from the gearbox;
a drill or screwdriver is applied to the drive, switched to unscrewing mode;
the ignition turns on;
pressing the button of the drill, rotate the drive.
In a situation where the speedometer needle begins to move, it should be recognized that the monitoring device is fully operational. This means one thing - the fault lies somewhere in the gearbox. Here, an exclusively experienced car enthusiast or a professional locksmith is able to independently repair the breakdown. When the arrow does not move from a place, it will be enough to replace the sensor itself.
As it is easy to understand, in most cases it is really possible to repair the speedometer on your own. However, in situations where there is no confidence in them, it is better to turn to experts. Wrong actions often lead to an aggravation of the problem, which, in turn, results in unnecessary expenses.
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