Wiper does not work: possible causes and solutions

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

Inoperative wipers not only cause inconvenience to the driver while driving in rain or snow, but can also cause a traffic accident. Having discovered such a breakdown in bad weather, it is better to abandon the trip and take measures to eliminate it.

In this article we will talk about the reasons why the wiper does not work, and also consider methods for their elimination using the example of a VAZ-2114 car.

Wiper windscreen design

The wipers at the "fourteenth" are driven by a mechanism consisting of:

• motor;
• control unit;
• elements of electrical protection;
• drive (trapezoid);
• 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 passenger compartment. It has a built-in reduction gear and is equipped with three brushes. It is they that allow you to adjust the speed of movement of the brushes on the glass.

Control unit

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

Wiper control unit has 4 positions:

• first (lowest) - the mechanism is off;
• second - wipers operate intermittently;
• Third - the brushes move fast;
• fourth - wipers move as fast as possible.

Protective elements

Electrical protection of the wiper circuit is carried out by a fuse. It is located in the main mounting block and is indicated in the diagram F-5. There is also a relay responsible for the operation of the wipers in intermittent mode. On the diagram, it is designated as K-2 or K-3.

Drive

The force from the electric motor to the brushes is transmitted using a trapezoid. It is a system of rods and levers that convert the torque of the motor into the reciprocating motion of the wipers. The trapezoid is also located under the hood, next to the electric motor.

Leashes and brushes

Each wiper consists of a leash and a brush. They are interconnected by means of a special fastener. The leash acts as a lever, transferring the force from the trapezoid crank to the brush. It is attached to the crank shaft by means of splines and a clamping nut.

The principle of operation of the mechanism

In order to find the reason why the windshield wiper does not work, you need to understand how it worksmechanism. And it works as follows. When we move the wiper control knob to the first position, voltage is supplied to the electric motor through the relay. Thanks to him, the wipers move in an intermittent mode, that is, with intervals between strokes. When the fast mode is on, they move with shorter pauses. Moving the handle to the highest position causes the wipers to move as fast as possible (without gaps).

Why the wipers don't work

Among the most common windshield wiper problems are:

• fuse blown;
• break in the electrical circuit (oxidation of contacts, disconnection of connectors, broken wires);
• relay failure;
• faulty control box switch;
• brush wear or short circuit (break) in the motor windings;
• jamming of drive levers (trapezoid);
• wear on the splines of the leashes.

Fuse

When you notice that the windscreen wipers have stopped working, the first thing to check is the fuse. It is he who is most often the cause of the malfunction. It is checked by "ringing" the tester. A burnt-out protective element must simply be replaced, and then the operation of the mechanism should be checked.

Open circuit

If the wiper blades still do not work after replacing the fuse, there may be a wiring problem. Check if the contact in the connectors is broken:

• blockcontrols;
• relay;
• motor.

If any traces of oxidation are found on the contacts of the connectors, clean them with fine emery cloth and treat with an anti-rust liquid (such as WD-40).

Relay failure

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

The wiper relay is only responsible for its operation in intermittent mode, therefore, it does not participate in fast and very fast modes. We turn on the ignition and move the wiper mode switch to the highest position. Did the wipers 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 duration of the pause between their strokes.

The delay is adjusted by moving the mode switch knob from the “On” position. to the second position, in which the wipers operate intermittently. At the same time, they start moving in the normal mode, with a shutter speed of about 4 seconds. Next, the knob is moved to the “Off” position, and the countdown for the programmable pause begins. The next time you turn on the intermittent wipers, the gap you maintained will be respected.

Faulty control unit

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

Often it fails not due to mechanical failure, but due to oxidation of the contacts. To detect possible causes, the block will have to be disassembled, inspected and, if necessary, cleaned the contact elements.

If this fails, the block should be replaced.

Electric motor problems

After checking the wiring and protection elements of the wiper circuit, and not finding a malfunction, we diagnose the electric motor that drives its mechanism. To do this, it is better to dismantle the engine.

Having done this, turn on the ignition and move the wiper control switch knob to fast or very fast mode. Using a multimeter, measure the voltage at the motor connector. The device should show the same voltage as on the battery. After making sure that the current reaches the electric motor, but it does not start, we can conclude that the wiper does not work precisely because of the engine malfunction.

Most often this happens due to wear of the current-carrying brushes, but sometimes the problem lies in the shorting of the turns of one of the windings. You can try to repair the electric motor by replacing the brushes, or restoring the windings, but it's easier to buy a new one. It costs within a thousand rubles.

Trapezoid malfunction andleashes

The trapezoid itself fails extremely rarely, because in order to break it, it will take a lot of effort. In most cases, problems with it occur after repair or replacement of the drive levers.

But as for the leashes, they often break. The main cause of the failure 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 wipers can cause them to “lick”. In such a situation, there is only one way out - replacement.

Rear wiper not working

VAZ-2114 is equipped with a rear window cleaner. Unfortunately, it sometimes fails. Fortunately, there are no fuses and relays. The rear wiper mechanism consists of an electric motor with a gearbox and a leash with a brush. Its inclusion is carried out by switching the handle away from you (horizontally).

Diagnosis of the rear wiper is also done by measuring the voltage at the engine connector. If it is supplied, you will either have to repair it or buy a new electric motor.