On cars produced by VAZ, two types of speedometer drives are used - electrical and mechanical. The latter was installed on classic models 2101-2107 and front-wheel drive 2108 - 2115 until the beginning of the first decade of the 21st century, after which they switched to installing an electronic speedometer drive. The basis of the speedometer drive of any type is a plastic gear inserted into the gearbox (gearbox). Its task is to transmit the rotation of the gearbox secondary shaft to an electrical or mechanical speedometer sensor.
What is the difference between the speedometer drive of the VAZ 2101, 2103, 2106?
Depending on the gear ratio of the rear axle gearbox, speedometer drives can be of three types. They differ in the number of driven gear teeth (12, 9, 13).
One of the rarest, almost “extinct” on the auto parts market is the 2101 drive without a mark with 12 teeth. It is suitable for Zhiguli gearboxes with a rear axle 2101, which has a gear ratio of 4.3. The VAZ 2102 station wagon (gearbox - 4.44) is also installed on older models, but has a larger reading error (“overestimates”).
Drive 2103 (9 teeth) is marked with red paint - for a gearbox with a rear axle 2103 with a gear ratio of 4.1.
Replacement on front-wheel drive vehicles
On models 2108 – 2115, the speedometer drive is located on the side of the gearbox on the rear wall of the engine compartment. It is accessible from the hood. The replacement technology is no different from that used on classics - remove the cable end or wire block (to do this, unfasten the latches), remove the speed sensor, unscrew the bolt securing the drive gear and remove it from the gearbox. The ratio of the number of teeth of the drive gear and the drive gear of the secondary shaft does not differ.
Basic speedometer faults
Malfunctions can be divided into two types:
- the speedometer does not show the current speed;
- The speedometer drive is noisy.
The VAZ 2107 speedometer may not work for the following reasons:
- The speedometer is faulty. In this case, the device must be replaced.
- The nuts securing the ends of the flexible shaft have come loose. To fix the problem, they need to be screwed on.
- The flexible shaft is broken. It must be replaced to restore the speedometer's functionality.
- The tip of the flexible shaft or the mating socket on the speedometer is damaged. In this case, you should change the VAZ 2107 speedometer cable or the speedometer itself
- The flexible shaft drive is faulty or the speedometer drive socket in the gearbox is damaged. This is a rare breakdown, the elimination of which involves repairing the gearbox and is worthy of description in a separate article.
Causes of breakdowns
The causes of breakdowns are usually associated with mechanical damage to one of the drive parts, but some malfunctions can occur due to contamination or lack of lubrication. The main manifestations and signs of a malfunction will help you diagnose the specific cause of the breakdown.
- If the arrow lies at zero and does not respond to acceleration, then, most likely, a broken drive cable is to blame for the breakdown. In this case, it will have to be replaced. However, such a malfunction can also be caused by other reasons, for example, a loosening of the nut securing the flexible shaft to the speedometer. In this case, a simple tightening of the nut will “cure” the speedometer needle from its vagaries.
- The speedometer making a knock may be due to dirt getting into the socket for attaching the flexible cable to the transmission secondary shaft, or to loosening of the fastening. In such a situation, it is necessary to inspect the seat of the drive gear to the drive shaft and eliminate the cause of the breakdown.
- The operation of the speedometer needle with an uncharacteristic sound is most often associated with a lack of lubrication of the flexible cable and, accordingly, its additional friction. Such a malfunction can be “treated” simply - the cable is coated with lubricant, after which the malfunction is eliminated.
- Cases when the speedometer needle goes off scale and lies motionless in this position are associated with a rupture of the opposing spring in the drive shaft. In this case, the drive changes completely.
- The high error in speedometer readings is associated with incorrect attachment of the flexible cable to the secondary shaft of the gearbox, which is why the speedometer receives incorrect impulses and, accordingly, rotation data. This problem can be corrected by adjusting the cable fastening.
Problems with the speedometer are not always associated with drive failure. For example, a malfunction of the electric motor of an electromechanical speedometer will also lead to malfunction of the device. To check the operation of the drive, you need to start the car, first hanging one wheel and supporting it so that when you engage the gear, the car does not move spontaneously. If in this case the drive rotates, then the problem is associated either with a malfunction of the speedometer itself or with a break in the drive cable. Otherwise, the drive is to blame and will have to be replaced.
Removing the VAZ 2107 speedometer cable
The procedure for removing the speedometer drive is as follows:
- place the car on a lift or inspection hole;
- disconnect the ground wire from the battery;
- dismantle the instrument panel;
- unscrew the nut securing the cable to the speedometer mechanism and uncouple it;Installing the VAZ 2107 speedometer cable
Before installing a new cable, it must be pulled out of the casing, lubricated with Litol grease and inserted into place.Next, you need to tie the guide wire to the nut securing the cable to the speedometer and pull it from the bottom of the car into the interior.
Further actions are performed in the reverse order of removing the speedometer cable.
After installing the cable, you must insert the rubber protective cover located on the braid. into a hole in the car body. through which the cable passes into the cabin.
This completes the repair of the VAZ 2107 speedometer
The reason for the malfunction of the device often lies in the fact that the VAZ-2107 speedometer drive has failed.
Types of drives
When purchasing a drive, you still need to be careful. It is advisable to first remove the drive and count the teeth, since their number varies.
There are several types:
- 9 teeth;
- 12 teeth;
- 13 teeth.
The installation of one or another drive depends on the installed rear axle, since they have different gear ratios. The 13 teeth are color coded blue.
If you are one hundred percent sure that the drive is faulty, then buy it. But I still recommend that you first figure out the reason why the speedometer is not working and only then make a purchase.
The drive can make noise for the following reasons:
- the cable has a small bending radius. Here it is necessary to re-route the drive;
- The cable sheath is damaged. In such a situation, it is necessary to replace the speedometer drive assembly.
As practice shows, the largest number of breakdowns of the VAZ-2107 speedometer are associated with its drive and can be eliminated by replacing the flexible cable. To do this you will need pliers and a screwdriver. To facilitate installation, you can use steel wire with a length of about 2 m and a cross-section of 0.5 mm. The drive is fixed in the lower part of the crankcase to the gearbox, so repairs require a lift or inspection hole.
How mechanical and electric drives work
While the car is moving, the speedometer drive gear, using a flexible cable, transmits rotation from the secondary shaft to the speed sensor located in the instrument panel. Different drive gears are used on different VAZ car models. This is due to the different transmission ratio of the gearbox (main gear). A higher ratio of differential teeth to drive gear allows the vehicle to reach higher speeds, but has a negative impact on dynamics.
A smaller ratio improves dynamics but limits top speed. In order for the speedometer to accurately display the speed, it is necessary to ensure the correct relationship between the drive gear located on the secondary shaft and the speedometer drive gear. When selecting a speedometer drive, take into account the size of the wheels and the transmission ratio of the vehicle's gearbox. This approach allows you to use a common speedometer for all models of each family.
Unlike a mechanical one, the electric speedometer drive transmits rotation not to the indicator, but to the speed sensor, which converts the gear rotation speed into signals understandable to the electronic control unit. This approach allows you not only to display the speed on the speedometer indicator, but to control the operation of the injector.
Dismantling the VAZ-2107 speedometer drive
The actions are performed in the following sequence:
- the car is installed on an inspection hole;
- the ground wire is disconnected from the battery;
- the instrument panel is removed;
- the nut securing the drive to the speedometer is unscrewed and it is disconnected;
- a wire is tied to the eye of the nut;
- the nut securing the flexible shaft to the gearbox is unscrewed;
- the speedometer cable is disconnected from the gearbox;
- the drive is pulled out so that the guide wire remains in it;
- the wire comes untied from the nut.
Replacing the speedometer "six"
In the VAZ 2106, the speedometer is replaced in case of defects that cannot be eliminated during repair work, as well as when the VAZ 2106 speedometer does not work for one reason or another. The procedure for removing and installing it does not involve any complex technological operations; even a novice car enthusiast can carry out the replacement.
We tell you how to change the speedometer on a VAZ 2106 according to the order of the actions performed. So:
- We place the instrument panel on ourselves, having previously pressed out the fasteners in the technological holes of the panel with a screwdriver from below;
- Having slightly pulled out the instrument panel, unscrew the speedometer cable of the VAZ 2106, attached to the fastener to the rear part of the device;
- We dismantle the speedometer cable on the VAZ 2106, after which the dashboard will receive some freedom of movement and can still be moved towards itself;
- Disconnect the plug connector with wiring from the device;
- We unscrew the 2 fastening wheels with teeth along the edges of the product, which serve to secure its clamps; in case of complications, you can use pliers;
- After this, the device mounts are released and it is necessary to disconnect the device from the cable of the daily mileage fixation mechanism. To do this, unsplint the fasteners and disconnect this cable.
Now we remove the device. The question of how to change the speedometer has been removed from the agenda.
The cost of a VAZ 2106 speedometer is not small, about 1 thousand rubles, although at car dealerships it can be found for no more than 300 rubles.
Tuning the speedometer "six"
For work you will need the following materials:
- cover from a computer disk box;
- knife;
- screwdriver.
Tuning is carried out as follows. An iron speedometer scale is placed on top of the disc cover. Next, it is outlined along the contour, after which the workpiece is cut out using a knife. You can also use a screwdriver for this purpose. This creates a new form of scale.
Next, you need to create the scale itself. To do this, you can use various computer programs. It is important to remember that the background is only black, and white is used for divisions, indicators and holes. If you have a printer at home, you can print the scale yourself.
But it’s better to contact a printing center, since the best option for this purpose is not ordinary paper, but film. On it, transparent places will indicate where the white color was. It should be remembered that there must be space in the drawing for the hole and for the odometer.
After this, the resulting film is glued onto a pre-prepared plastic form. Care will be required here, since it is very important that the film does not bubble and that all holes coincide with the slots. Now a light filter is attached to the back side. Then they work with the white scale.
It is best when the printed numbers have an outline. To choose the best option, you can make several samples on a regular printer. The scale is placed in the center. The final step will be to install the device in the car. The cost of such a hand-made craft will cost pennies.
You might want to think about another lighting option. To do this, the device body is disassembled and all internal mechanics are removed. It is also necessary to remove the filter and remove the partition under it. Additional lighting can be done using LEDs or simple light bulbs.
In order to secure additional lighting devices, there is an iron element on the right side designed to transmit minus to the indicator lamps. On the left side the lighting fixture is secured with a screw.
Next, you need to weld the wires and check. With proper fastening and installation, not only the divisions themselves will be illuminated, but also the entire circumference of the speedometer. If the result is satisfactory, the protective glass is installed in place.
A very important point is that before installing the speedometer in place, it is advisable to evaluate the visibility of the numbers from different viewing angles. This will help you determine where you need to add colors on the scale or add light bulbs.