The heated rear window of the VAZ-2107 does not work, what should I do?

↑ Connection diagram for heated rear window of VAZ 2107

• 1. Mounting block
• 2. Ignition switch
• 3. Heated rear window switch
• 4. control lamp for turning on the heated rear window
• 5. Rear window heating element
• K6 - Additional relay
• K7 - Relay for turning on the heated rear window
• A - Power supply

The description of the rear window heating circuit is as follows. On its surface, on the right and left, two busbars run vertically; wires are connected to them, through which a voltage of 12 V is supplied. The busbars are connected to each other by conductive horizontal strips 2-3 mm wide, which are the main working tool.

By passing an electric current, they create a positive temperature on the surface of the glass, freeing it from freezing or fogging. Like any electrical appliance, it is controlled by a fuse designed for the intended voltage and current.

Heater device

First of all, let's carefully study the structure of the object in question. On the rear window of a car there are conductive threads that heat up due to the fact that current passes through them. They create heating. Its voltage is maintained by elements such as relays, wiring and fuse. This elementary circuit ends, of course, with a power button.

The diagram below describes in detail the structure of the heater of the VAZ 2107 car:

• mounting block or so-called “block”;
• on/off relay;
• egnition lock;
• on/off button;
• warning light on the dashboard;
• heating filaments on the rear window.

↑ How to check the heated rear window

If it is discovered that the device has failed, the question arises of how to check the heated rear window. It's not difficult, proceed in the following sequence:

1. Check the fuse. If it burns out, it is replaced.
2. Measure the voltage on the wires supplying power to the device. It should be at least 11 V. If the voltmeter shows a lower value, it means that the contacts on the connectors have oxidized. The terminals should be cleaned with fine-grained sandpaper and a rust remover. It is worth checking the reliability of the power supply connection. A loose contact can also cause a breakdown.
3. The most common cause of heater malfunction is rupture of the conductive threads. It breaks easily under the influence of a light touch. Visual inspection of the threads will reveal the location of separation. Torn edges are black. To restore the functionality of the device, it is necessary to repair the gap.
4. If all of the above actions are performed, but no breakdown is detected, the switch button may be faulty or the wires may be broken. First you should examine the button, then diagnose the wiring.

↑ Restoring the integrity of conductive strips

Repairing a heated rear window is easy if you buy a rear window repair kit from a car store. It contains conductive adhesive that works at temperatures from -60°C to +100°C.

↑ Step-by-step instructions for restoring threads:

1. Carefully clean the edges of the strips at the breakage point to remove carbon deposits and dirt from the glass. The finest sandpaper is best.
2. Wipe with alcohol.
3. Place tape close to the sides of the strip on the glass. You should act carefully so as not to overlap the thread, but also not to create gaps between the tape and the strip.
4. Apply conductive glue to the prepared areas, overlapping the strip on each side of the break by 1 cm. The number of layers is determined in the instructions for the product. The glue is applied to cold glass.
5. After 24 hours, when the composition has dried, check its functionality by first removing the tape.

↑ Alternative conductive compounds

If factory-made conductive adhesive is not available, it is possible to use other compounds:

• Prepare the breakage area as before applying factory glue. But you will need fine iron filings, a magnet and transparent glue. The magnet is applied to the tape above the conductive thread, and iron filings are applied. The magnetic field forces the iron particles to position themselves along the thread, filling the void at the break point. Transparent glue is applied over the sawdust to secure it. You can check the functionality after 1.5-2 hours.
• After the preparatory work, non-ferrous metal shavings are mixed with paint to obtain a plasticine-like mass. It is used to fill the groove at the break point when the heater is on. A brief hissing sound will be heard. The mixture hardens for 20-30 minutes. The device can be used after 1 hour.

Heated rear window of the VAZ 2107 plays an important role in ensuring traffic safety. This is a simple device, the breakdown of which is easy to diagnose and repair. You can restore functionality yourself and it won’t take much time.

How to fix the heating of a VAZ2107 with your own hands

To eliminate the causes of malfunctions, you will need the following devices:

• multimeter or voltmeter;
• foil.

Identifying the cause throughout the entire circuit

The most common failure of a defroster is a blown fuse. Until some kind of breakdown occurs, for example, failure due to a blown cigarette lighter fuse, the location of the unit and the fuses themselves are not known.

1. Step No. 1 - in VAZ 2107 cars, the fuse that is responsible for heating the rear window is located in the fuse block under the designation F5.
2. Step No. 2 - if the fuse is working, then the next step is to check the heater terminals on the glass and for ground.
3. Step No. 3 - check the control unit connector (relay and toggle switch (on/off button)).
4. Step No. 4 - checking the heating filaments with a tester.
5. If the above steps do not reveal the cause, then Step #5 is to check the ignition switch contacts or fuse block board.

Step-by-step guide to diagnosing defroster filaments:

1. To ensure that the heating filaments are not damaged by the sharp tips of the probes, it is necessary to wrap pieces of foil around the probes of the measuring device (voltmeter or multimeter in position “B”).
2. Turn the ignition key and turn on the heating switch.
3. One probe of the measuring device must be connected to the positive wire, the second - to the middle of the wire (see figure).
4. The value in volts should be 6. If it shows 6 V, then the heater filaments are working.
5. If the value on the device displays 12 V, then the thread is broken between these two points.
6. If 10 V is visible on the screen, then the thread is broken from the midpoint to the negative point.
7. Next, you need to move the probes to the right, from the middle point to the right vertical stripe (minus), from the “plus” to the middle. If in this section the meter shows from 0 to 5 V, then this section of the circuit has a break.

Diagnostics of heater filaments with a voltmeter

Before repairing threads, you need to buy a repair kit in advance, and then do the repairs in this order:

1. Clean the torn section of thread with alcohol.
2. Along the length of the thread, above and below it, we evenly glue electrical tape (you can use adhesive tape, but electrical tape is more convenient). The width between the two strips of electrical tape is equal to the width of the heater filament.
3. We apply a special solution with a brush (called a kit for repairing rear window defroster filaments) along the entire length between the electrical tapes. It would be more effective to trim the brush, remove the side sticking hairs, so as not to smudge the electrical tape and avoid overspending.
4. We wait until the solution dries naturally, that is, we do not turn on the heater. Natural drying time is about 1 day.

Which car lamps are the most popular? Lamps H8 and H11 have some differences, but are interchangeable.

Recommendation for choosing a special regenerating agent for the glass heater:

• the color of the solution should be red-cinnamon (in practice, gray color did not work);
• the cost of a good working special tool is about 350-400 rubles (bought for 150 rubles, I could not restore the thread).

How to improve your windshield

As you know, in VAZ 2107 cars the manufacturer did not provide such a function as a heated windshield. There is only its airflow, which allows you to remove the effect of “foggy glass”. If you want to improve your car, then you can become the owner of a heated windshield. This athermal glass can be installed independently without any problems, since all the necessary components are included with it.

This type of glass is ideal for the VAZ 2107, so a snowy, frosty morning will no longer be able to ruin your mood. Of course, heated glass is quite expensive compared to its simple counterpart. But you definitely won’t regret this windshield improvement.

Causes of problems

• If the power button does not light up and the glass does not fog up, then most likely the control for turning on the heating relay has failed. In this case, you should check whether there is voltage on it.
• If the glass also does not defrost and the button does not light up, then, presumably, the control for turning on the heating relay is not working. The diagram will help you diagnose control voltage and ground, indicated on the relay as 85 and 86 and wires numbered 1, 2, 4, 9, fuse F7, power button.
• If the rear window heating does not work and the control light on the dashboard is on, then it is worth checking the power to the wires numbered 5, 19, 30, fuse F4 and whether the heating element is in working condition.
• If, when this function is turned on, the glass clears unevenly, it means that some of the threads carrying current have been damaged. In this case, the circuit is no longer needed. Below we will tell you how to solve this problem.

Fuse and relay block VAZ 2107

When diagnosing electrical faults, it is very convenient to use a multimeter. Using it, you can ring any connections and devices to check their functionality. If you know how to use it and have at least minimal knowledge of electrical engineering, I think it will not be difficult for you.

Owners of cars with a heated rear window enjoy a huge advantage over drivers of cars that do not have a heated rear window or it does not work.

VAZ 2107 fuses and relays, electrical diagrams

Often when operating a VAZ 2107 we encounter electrical problems. At one point, one of the electrical appliances, such as a stove or low beam headlights, refuses to work. Dimensions, cigarette lighter, turn signals and other components of the vehicle's electrical circuit may also stop working without warning.

To find the cause of the malfunction, you first need to understand whether voltage is supplied to a particular device and check the fuses and relays of the VAZ 2107. The most important thing in the circuit is the fuse. It protects the device from overloads and failure. If there is any short circuit or if the current in the circuit increases significantly, the fuse will blow. Therefore, first of all, let's open the hood of the car and check the fuses.