Do-it-yourself speedometer repair

In detail: do-it-yourself speedometer repair from a real master for the site my.housecope.com.

Compliance with the speed prescribed by the rules is a guarantee of safety on the roads. Therefore, you need to monitor the status of your car's speedometer. It's okay if the speedometer shows more speed than it actually is. It is much more frightening when this actual speed is higher than the indicated one. Therefore, in the event that the speedometer is faulty, repair is necessary. A real chauffeur repairs everything with his own hands, so in this article you will learn how to repair a speedometer and wind up an odometer.

If you are not afraid of difficulties, you can carry out repairs yourself.

The following auxiliary items are required for the repair process: a car repair and operation book, a set of tools, a sealant and a simple travel plastic plug.

Before disassembling the car, you need to read how it is done. The repair book often indicates the reasons for the breakdown and the rules for their elimination. Therefore, it will be useful to open the electrical section of the book.

Most often, a speedometer malfunction lies in the fact that the speedometer needle constantly jumps left and right, or it froze in place and does not move.

If you nevertheless decide to do the work yourself, and not contact specialized services, where you can easily correct the speedometer for a Ford, Mercedes, Peugeot, etc., then it is better to carry out repairs in the garage, where there is good lighting and there is no wind influence and street dust. It is better to put the car on the handbrake, turn off the minus from the battery so that a short circuit does not occur.

To access the speedometer, you must first remove the steering wheel, the switch socket from under the steering wheel, and unscrew the torpedo mounting bolts. And only after that the torpedo should be easily dismantled. The dashboard can now be removed. To do this, unscrew the bolts, remove it. And then, by heating with a hairdryer, remove the plastic glass. After that, you should wipe the places where there are remnants of the sealant.

Video (click to play).

A common problem that arises when a speedometer breaks down is a cable break. In the event that it is cut off, it should be replaced. Sometimes it happens that the needle bends. Then it can be removed with a fork prepared in advance. Prying the arrow a little, it jumps out without difficulty. It also needs to be replaced.

Also on the back of the panel are gears that ensure the correct operation of the speedometer. They should be inspected and replaced if necessary if the teeth are broken. Now that the breakdown has been fixed, you can put everything in place. This is where the sealant is needed, which holds the plastic glass.

A speedometer is a device designed to measure the speed of a vehicle. In the modern automotive industry, an electronic version of the device is mainly used.

The domestic automotive industry began to use an electronic speedometer since the release of the VAZ-2110, the power supply system of which was based on an injector.Image - DIY speedometer repair

Therefore, if the speedometer does not work even on relatively old cars, the reason should be sought in the wiring elements.

The speed measurement system in a modern car includes such elements as:

  • Speed ​​sensor installed in the gearbox;
  • Electronic engine control unit;
  • Speedometer display on the instrument panel;
  • Wiring.

The electronic control unit calculates the speed of the machine based on the frequency of the pulses it receives. This is the principle of operation of an electronic type speedometer. In parallel with the correction of engine operating modes, the control unit transmits information about the speed of the car to the speedometer and diagnostic block.Image - DIY speedometer repair

If there is a trip computer with "K" DC output, speed data can be duplicated on its scoreboard.

If the speedometer stops working, troubleshooting is carried out in several directions. The failure can be caused by the following breakdowns:

  1. Failure of the speed sensor;
  2. Damage to electrical wiring;
  3. Oxidation of "mass" contacts;
  4. Malfunction of the speedometer itself;
  5. ECU malfunction;
  6. Incorrect installation of the instrument panel after removal.

The diagnostic sign of a blown fuse F19 is:

  • Failure of the entire instrument panel;
  • Failure of the diagnostic unit;
  • Failure of the automatic door locking system;
  • Failure of reversing lamps.

Before replacing a fuse, it is advisable to find out and eliminate the cause of the blown fuse. In most cases, this happens when there is a short circuit in the wiring system of a VAZ-2110 or VAZ-2114 car.

Fault diagnostics begin by disconnecting the wire harness from the speed sensor harness and checking them using a warning light.

To make a control light bulb, you need any car lamp capable of operating at a voltage of 12 V, and two wires about 1 meter long each. One of the wires is fixed to the positive terminal, the other - to the negative terminal of the lamp. Also, the received device includes a battery of the "Krona" type.Image - DIY speedometer repair

To carry out the test, one wire of the test lamp is fixed to the body or battery ground, and with the second, short frequent touches are made to the middle contact of the DS connector. If there are no faults in the section, the connector is the speedometer, the arrow of the latter will slightly shake or rise. If the arrow shakes, the answer to the question why the speedometer does not work can be considered found - the speed sensor needs to be replaced.

In cases where the reaction of the arrow to tapping on the central contact of the pads cannot be detected, it is necessary to "dial" the speedometer power circuit. The procedure is carried out using a multimeter (multitester), or by using the same control lamp.

If the tester in the "continuity" mode indicates a violation of the continuity of the circuit, further troubleshooting is carried out in this direction. It is necessary to check the fuses, wire connections, their integrity inside the insulating braid.

The search area can be reduced by gradually “ringing out” individual sections of the chain. On model 2114 and other VAZ products, the reason for the failure of the speedometer is often the oxidation of "mass" contacts fixed on the car body.

In cases when the speedometer needle does not work, however, there is no data on faults in the electrical supply circuit, a natural conclusion is made about the malfunction of the device itself. Additional verification can be done by temporarily installing a known-good dashboard.Image - DIY speedometer repair

Repair of the speed measuring system directly depends on the detected malfunction:

  1. Clean from contamination;
  2. Clean the pads' contacts from corrosion and oxides;
  3. If the above measures do not help, the sensor is replaced.
  • Check and clear "bulk" contacts;
  • To solder or fix with the help of "twists" the places of the broken wires, due to which the speedometer stopped working;
  • Cover the damaged areas of the sheath with insulating tape;
  • Replace defective fuses;
  • Clean the pads contacts from oxides and corrosion.