Wiper does not work: possible causes and solutions

Non-working janitors not only cause inconvenience to the driver during driving in rain or snow, but can also cause a traffic accident. Finding such a breakdown in bad weather, it is better to abandon the trip, and take measures to eliminate it.

In this article, we'll talk about the reasons why the windshield wiper does not work, and also consider the methods of their elimination using the example of the VAZ-2114.

Windscreen Wiper Construction

The janitors at the "fourteenth" are set in motion by means of a mechanism consisting of:

• The electric motor;
• The control unit;
• Elements of electrical protection;
• Drive (trapezium);
• Leashes with brushes.

Engine

The wipers are driven by an electric motor, located under the hood near the partition separating the engine compartment and the interior. It has a built-in reduction gear and is equipped with three brushes. They allow you to adjust the speed of brush moving on the glass.

Control block

The wiper control unit is located on the steering column on the right side. Its role is to include the wiper and switch its speed settings.

The wiper control unit has 4 positions:

• The first (the lowest) - the mechanism is turned off;
• The second - the janitors work in intermittent mode;
• The third is that the brushes move quickly;
• The fourth - janitors move as quickly as possible.

Protective elements

The electric protection of the windscreen wiper chain is provided by a fuse. It is located in the main assembly block and is indicated on the diagram F-5. Here is the relay, which is responsible for the operation of the wipers in intermittent mode. In the scheme it is designated as K-2 or K-3.

Drive unit

The force from the electric motor to the leashes of the brushes is transmitted by means of a trapezoid. It is a system of links and levers that convert the torque of the motor into reciprocating janitors. Trapezium is also located under the hood, next to the electric motor.

Leads and brushes

Each janitor consists of a leash and a brush. They are connected by means of a special fastener. The leash performs the function of the lever, transferring the brush force from the trapeze crank. To the crank shaft, it joins by means of the splines and the clamping nut.

Principle of operation of the mechanism

In order to find the reason why the windshield wiper does not work, it is necessary to understand how its mechanism works. And it works as follows. When we move the handle of the wiper control unit to the first position, the voltage is applied to the motor through the relay. Thanks to it the wipers move in discontinuous mode, i.e. with intervals between swings. When the fast mode is on, they move with less long pauses. Moving the handle to the uppermost position causes the wipers to move as quickly as possible (without gaps).

Why do not windshield wipers work?

Among the most common problems associated with the operation of the mechanism for cleaning the windshield, we can distinguish:

• Fuse blown;
• Breakage in the electrical circuit (oxidation of contacts, disconnection of connectors, breakage of wires);
• Failure of the relay;
• Malfunction of the control unit switch;
• Wear of brushes or shorting (break) in windings of the electric motor;
• Jamming of the drive levers (trapezium);
• Wear of slots of leashes.

Fuse

Noticing that the windshield wipers are no longer working, first check the fuse. It is most often the cause of the malfunction. It is checked by "ringing" the tester. The burnt out protective element must be simply replaced, then check the operation of the mechanism.

Break in the chain

If the wiper blades do not work after the fuse has been replaced, there may be a problem with the wiring. Check if the connector is broken:

• The control unit;
• relay;
• Electric motor.

In case of detection of oxidation traces on the contacts of the connectors, peel them with a fine emery cloth and treat them with a liquid against rust (type WD-40).

Relay failure

Another reason why the wiper does not work, can be a relay. First, remove it from the seat in the mounting block and insert it back. Often the problem is the banal oxidation of contacts. If this did not help, we leave it in the assembly block and go to the salon.

The relay of a screen wiper is responsible only for its work in the intermittent mode, hence, in fast and very fast modes it does not participate. We turn on the ignition and switch the jumper mode switch to the highest position. Did the janitors work? We change the relay. By the way, its catalog number for the "fourteenth" is 52.3747 or 525.3747, and it costs about 150 rubles. A little more expensive (about 250 rubles) will cost an adjustable wiper relay, which will allow you to adjust the length of the pause between their swings.

Adjustment of the delay occurs by switching the mode selector from "On" to the second position, at which the windshield wipers operate intermittently. At the same time, they begin to move in normal mode, with an exposure of about 4 seconds. Then the knob is moved to the "Off" position, and the time for the programmable pause starts. The next time you turn on the wipers, intermittent operation will keep the gap between you.

Malfunction of the control unit

A sign of a malfunction of the control unit is the lack of reaction of the windshield wiper mechanism with a known good fuse, electric motor and the whole wiring.

Often, it breaks down not because of mechanical failure, but because of the oxidation of contacts. To detect possible causes, the block will have to be dismantled, inspected and, if necessary, cleaned up contact elements.

If this does not help, the unit should be replaced.

Problems with the electric motor

After checking the wiring harness and the wiper guard components, and not finding a malfunction, we diagnose the motor that drives its mechanism. For this, the engine is better to be dismantled.

Having done this, turn on the ignition and turn the shift knob of the wiper control unit to fast or very fast mode. Use a multimeter to measure the voltage in the motor connector. The device should show the voltage is the same as the battery. Having made sure that the current reaches the electric motor, and it does not start at the same time, it can be concluded that the windshield wiper does not work precisely because of the engine malfunction.

Most often this happens due to the wear of current-carrying brushes, but sometimes the problem also lies in the closure of the coils of any of the windings. The electric motor can be tried to repair, replacing the brushes, or restoring the windings, but it's easier to buy a new one. It is worth a thousand rubles.

Malfunction of trapeze and leashes

By itself, the trapezium fails extremely rarely, because in order to break it, it takes a lot of effort. In most cases, problems with it arise after repair or replacement of the drive levers.

But as for leashes, they break often. The main cause of the malfunction is the wear of the splines. The fact is that they are made of aluminum, so even a small effort, applied in the direction opposite to the movement of the janitors, can cause them to "lick". In this situation, there is only one way out: replacement.

Rear wiper does not work

VAZ-2114 is equipped with a rear screen wiper. Unfortunately, and it sometimes breaks down. Fortunately, there are no fuses and relays. The rear screen wiper mechanism consists of an electric motor with a reducer and a leash with a brush. It is switched on by switching the handle away from you (horizontally).

The rear wiper is also diagnosed by measuring the voltage at the engine connector. If it is supplied, it will be necessary either to repair or buy a new electric motor.