How to test a relay regulator with a multimeter

The presence of various electronic assistants in the car allows the driver not to worry about adjusting many systems and mechanisms. Some processes would be completely impossible to control without a partner if automatic devices that perform this function had not been developed and implemented in the electronic circuit of the vehicle. For example, in the absence of a generator voltage relay-regulator, it would not be possible to stably and safely extract electrical power from the generator to charge the battery.

Why do you need a voltage regulator in a car?

This small, simple device performs an important function - voltage regulation. That is, if the voltage is greater than set, the regulator should reduce it, and if the voltage is less than set, the regulator should raise it.

What voltage does the generator relay regulate?

When the engine is running, the generator operates, which generates and transmits electric current to the battery.

If the voltage regulator does not work correctly, the car battery quickly drains its life. The regulator is sometimes called a pill or a chocolate bar.

Types and types of relay regulators

Depending on the type of relay, the method for determining performance also depends. Regulators are classified into 2 types:

Combined relays - this means that the relay itself with the brush assembly is located in the generator housing.

Separate relays - this means that the relay is located outside the generator housing and is mounted on the car body. You've probably seen a small black device attached to the fender of the car, wires go to it from the generator, and from it to the battery.

A distinctive feature of regulators from other devices is that the relays consist of a non-separable housing. During assembly, the body is glued with sealant or special resin. There is no point in disassembling and repairing it, since such electrical appliances are inexpensive.

Signs of trouble

If the voltage is low, the battery will not be able to charge. Thus, the battery will quickly run out.

If, after the relay-regulator, the voltage goes to the battery at a high level (higher than set), the electrolyte will begin to boil and evaporate. At the same time, a white coating appears on the battery.

What signs of a breakdown of the car generator voltage regulator may be:

After turning the ignition key, the warning lamp does not light up.
After the engine starts, the battery indicator does not go out on the instrument panel.
In the dark, you can observe how the light becomes brighter and dimmer.
The car's internal combustion engine does not start the first time.
If the engine speed exceeds 2000, then all the dashboard lights may turn off.
Loss of engine power.
Battery boiling.

Causes of relay malfunction

The reasons include the following observations:

Short circuit (SC) on any line of automotive electrical wiring.
Diodes are broken. The rectifier bridge has closed.
The battery terminals are not connected correctly.
Water got inside the relay.
Mechanical damage to the housing.
Brush wear.
The relay resource has expired.

Checking the functionality of the regulator

When diagnosing the generator voltage regulator, it is necessary to determine what breakdowns may be revealed during inspection (in order to avoid further malfunctions and effectively carry out preventive procedures).

Malfunctions while driving the car

The light on the panel and other light sensors do not light up.
The battery is low/overcharged and the regulator button is dark/bright.

The breakdowns can be as simple as a loose belt, a burnt-out relay, or worn out brushes.

To check the device you will need the following tools:

sets of keys and screwdrivers;
various testers;
lamp 12 Volt 3 Watt;
wires for connection;
regulating current sources.

Checking the voltage regulator of the VAZ 2114 generator is carried out together with brush holders in order to immediately check the entire mechanism. You should carefully examine the condition of the brushes, their fragility, mobility, and length.

Check without removal. Using a voltmeter, we measure voltage readings. The optimal result is 13.5 - 14.2 V. If the data does not correspond to the norm, then there is a high probability of mechanism failure.

Before checking the voltage regulator and removing it from the car, you need to make sure that the fault lies in it and not in other components of the generator. How can I check this?

The first test option is diagnostics with the engine running using a voltmeter

What should be done? Start the engine and check the indicator light; if it does not go out and flashes brightly, it means there are problems in the generator. After a few minutes, when the engine increases speed and creates maximum conditions for the network load, we connect the meter and set 3500 rpm. Less than 13 Volts - the battery is completely discharged, when more - the regulator on the car needs to be replaced.

When you hear unusual noise from the unit, it means the bearings have failed, resulting in the drive belt being too tight. To adjust it, you need to turn off the ignition and release it. The deflection when pressed should not be less than two centimeters.

How to quickly and easily check the voltage regulator

Take a multimeter or voltmeter and measure the voltage at the battery terminals. The check is done in the following order:

Put the device in voltage measurement mode at up to 20 V.
Start the internal combustion engine.
At idle speed, measure the voltage at the battery terminals. In XX mode, engine speed is from 1000 to 1500 rpm. If the generator and voltage regulator are working properly, then the voltmeter should show a voltage of 13.4 to 14 Volts.
Raise engine speed to 2000-2500 rpm. Now the voltage value with the generator and relay working properly, the multimeter (voltmeter, tester) should show a voltage from 13.6 to 14.2 V.
Next, step on the gas and increase the engine speed to 3500 rpm. The voltage of working devices should be no more than 14.5 Volts.

The minimum permissible voltage that a working generator and voltage regulator should produce is 12 Volts. And the maximum is 14.5 Volts. If the device shows a voltage value less than 12 V or more than 14.5 V, then the voltage regulator must be changed.

In new cars, mainly the relay is combined with a generator. This helps avoid pulling separate wires and saves space.

Repair or replacement of the voltage regulator - what to choose

When various parts fail, the driver often makes a difficult decision: repair the part and install a new one. With a car relay regulator, such a dilemma arises only when using a car that was produced several decades ago. It is almost impossible to purchase new spare parts for rare car models, and disassembled parts may be of dubious quality. When an integrated device (chocolate bar) is used to adjust the battery charge level, such a device cannot be repaired. The parts installed in relay regulators of this type can be restored, but this work will require certain knowledge and skills, as well as significant time investment.

Replacing the generator relay regulator

If the relay regulator can no longer be used for its intended purpose, then a new part should be installed. The combined element changes in the following sequence:

Disconnect the negative terminal of the battery.
Disconnect the fasteners.
Remove the brush assembly cover.
Disconnect the diode bridge.
Unscrew the contact group nuts.
Unscrew the threaded elements holding the regulator.
Remove the part.

Installation of a new regulator is carried out in the reverse order of removal. When performing this operation, the element contacts must be connected correctly.

Depending on the generator model, the process of replacing the relay regulator may differ slightly. The main thing is to perform dismantling, if possible, without damaging other elements of the generator set.

Replacing an individual element is much easier. For this purpose, it is enough to disconnect the main 2 contacts from the device, remove the product from the car body and install a new part in its place. Then correctly connect the previously removed wires and check the operation of the device. To do this, just start the engine and measure the voltage at the battery terminals at different speeds.

Voltage regulator repair

You can try to disassemble and repair old models of relay regulators that are installed separately. It should immediately be noted that such an activity has little promise, but if you ring the internal elements with a multimeter and find the burnt part, you can completely restore the functionality of the regulator.

Repairing the regulator relay can take too much time, so it is much easier and more correct to purchase a new product or remove the device from another car in which this part is in known good condition.

To find out whether a car relay-regulator is working correctly or not, it is enough to carry out simple diagnostics using a multimeter or a test lamp. If the device being tested does not show signs of life, then it is enough to change the part to restore the functionality of the electrical system. Repairing a “chocolate” or “tablet” is practically impossible, but other types of regulators can also be restored with great difficulty. Therefore, if the battery is not charging or too much voltage is supplied to the battery, you need to purchase a new product from a specialized store.

Checking the VAZ 2107 regulator

Until 1996, classic VAZ 2107 cars with a cipher generator 37.3701 were equipped with an old-style voltage regulator (17.3702). If such a relay is installed, then it should be checked as on the top ten (discussed above).

After 1996, they began to install a new generator of the G-222 brand (there is an integrated regulator RN Ya112V (B1).

Checking the regulator separately

1 - battery;
2 - voltage regulator;
3 - control lamp.

To check, you need to assemble the circuit shown in the figure. At a normal operating voltage of 12 V, the light bulb should just glow. If the voltage reaches 14.5 Volts, then the light should go out, and when it drops, it should light up again.

Checking relay type 591.3702-01

Relay test diagram:

Such old relay models are sometimes installed on the classic VAZ 2101-VAZ 2107, on GAZ, Volga, Moskvich cars.

The relay is mounted on the body. It is checked according to the same scheme as the previous ones. But, you need to know the contact markings:

“67” is the minus (-) contact.
"15" is a plus.

The verification process is the same. At normal voltage, 12 Volts and up to 14 V, the light should light. If lower or higher, the light should go out.

PP-380

The RR-380 brand regulator was installed on VAZ 2101 and VAZ 2102 cars. Adjustable voltage at the temperature of the regulator and the environment (50±3) ° C, V:

at the first stage no more than 0.7
at the second stage 14.2 ± 0.3
Resistance between plug “15” and ground, Ohm 17.7 ± 2
Resistance between plug “15” and plug “67” with open contacts, Ohm 5.65 ± 0.3
Air gap between armature and core, mm 1.4 ± 0.07
Distance between contacts of the second stage, mm 0.45 ± 0.1.

Testing a three-level relay

As the name suggests, such relays have three voltage levels. This is a more advanced option. The voltage levels at which the battery will be disconnected from the voltage regulator can be set manually, for example: 13.7 V, 14.2 V, 14.7 V.

How to check the generator

To check functionality, you need to:

Disconnect the wires going to terminals 67 and 15 of the regulator.
Connect a light bulb to the wires. Bypassing the relay.
Disconnect the positive terminal of the battery.

If the car does not stall, then the generator is working.

Testing the removed regulator (with circuit)

An electronic relay is most often mounted on the surface of the generator next to the generator shaft along which the brushes move, in the area of the generator armature slip rings. The entire combined unit is covered with a plastic cover. It is removed with a screwdriver, the shape of which can be either a cruciform or a hexagon.

Stages of work:

Unscrew the two fastening bolts and remove the cover.
We take out the brush assembly.
We clean it from graphite dust.
We assemble the circuit using a power supply, charging or a voltmeter. We find a simple 12V lamp from the car, maybe with “dimensions” and wires to connect the entire circuit into one. We use a battery if the charger does not work without it. We connect the wire from it to the regulator, and connect the lamp to the brushes using “crocodiles”. When everything is connected correctly, the lamp will begin to glow because the brush assembly serves as a conductor of electricity from the shaft.
We raise the charging voltage to 14.5V, the light should go out, since such voltage as a “cutoff” further increases the voltage. By reducing the voltage on the charger, the lamp should light up again. If the voltage rises to 15–16V and the lamp is on, it means the relay is unusable.

Relay-regulator test circuit

Using the same principle, you can check a separate type of regulator of a new type. To do this, you need to disconnect it from the body or cover of the generator and attach it to the circuit. Carry out the check in the same way. As for the old type of relay-regulator installed on kopecks, you need to check it a little differently. Their markings are “67” and “15” . The first contact “67” is a minus, and “15” is a plus. Otherwise the principle is the same.

Interesting on the topic:

relay voltage regulator

New type voltage regulator. How to check. 1 part.

The malfunction of the car generator is classified as critical, in which further operation of the vehicle is not allowed. You can use a multimeter to check the functionality of the generator.

Video

Useful video for auto electricians.

How the generator and voltage relay work.

If you find problems with charging the battery from the generator, you need to check the regulator relay. This device is directly responsible for the normal operation and efficiency of battery charging. Moreover, the overall service life of the battery will depend on the health of the regulator relay.

The job of the regulator relay is to accurately maintain the voltage produced by the vehicle's alternator. In other words, the relay regulator functions as a voltage stabilizer. The device keeps the voltage within strictly specified limits, limiting the possible decrease or increase in the value. This regulation occurs constantly and does not depend in any way on the speed of the crankshaft and generator, as well as on the degree of load created by various consumers in the on-board network. It turns out that the relay regulator controls the “plus” of the battery, supplying or stopping the supply of electricity depending on the voltage reading at the battery terminal.

Read in this article

How to check the relay regulator yourself

To check the proper operation of the regulator relay, you can remove the device from the car. The second way would be diagnostics directly on the car. To perform the work you will need a test lamp and a multimeter tester.

It is also necessary to prepare a special power supply or charger, wires in advance, and also make sure that the battery is in working condition.

To check the relay regulator, you need to set the voltmeter mode on the multimeter to be able to measure direct current in the range from 0 to 19 volts.
Next, connect the multimeter probes to the “poles” of the battery with the engine turned off. Record the data that the voltmeter shows. The voltage should be between 12 and 12.5 volts. After this, the engine starts, and the voltmeter readings are recorded again. Normally, there should be an increase in values after starting the internal combustion engine to an average of 13-13.5 volts.
Additionally, it is worth considering that as the engine speed increases, the voltage should also increase. In the middle range this figure is about 14 volts, at high speeds it reaches 14.5.

How to check a VAZ 2107 generator: is the winding to blame?

However, your problem could also arise due to a faulty generator winding.
To check this element, take a multimeter, set it to the “resistance measurement” operating mode, and then connect the positive probe to terminal “30”, and the negative one to the generator. We check the diodes for breakdown. If the device shows a resistance value close to zero, most likely there has been a diode breakdown or a short circuit in the stator winding. We check the positive diodes: the positive probe to pin “30”, and the negative probe to the rectifier block bolt. A resistance close to zero indicates that a breakdown of one or several diodes has occurred. Conclusion: to solve your problem you need to check 1) drive belt 2) field winding 3) diode bridge

Tips and tricks

A common culprit for malfunctioning regulator relays may be oxidation of its terminals. This oxidation results in significant voltage loss. In this case, it is necessary to thoroughly clean the contacts and recheck. The voltage reading at the contacts should be similar to those given by the battery itself, that is, there should be no noticeable losses. Reduced voltage at the contacts indicates that they should be cleaned, and the regulator itself is often in working order. After cleaning, the terminals can be additionally treated with special chemicals that prevent further oxidation.

Finally, I would like to add that the cost of the regulator relay is not high. One of the surest ways would be to replace it with a new element if malfunctions are detected in its operation. Moreover, integrated relay regulators are a part in a monolithic housing that cannot be disassembled for repairs. Savings on this device are not justified, since rapid battery failure or a significant reduction in battery life will entail more serious costs when it is necessary to replace the battery.

Correctly charging a car battery with a charger. Before charging, check what current to charge the battery with. How to charge a battery without a charger.

The principle of operation and design of a car generator. The components of an alternator in a car: rotor, stator, windings, regulator.

How is the density of electrolyte in a battery measured, what does this indicator depend on. Affordable ways to increase the density in battery “banks” with your own hands.

For what reasons does the electrolyte in the battery become cloudy, gray or black? In what cases and in what ways can you restore battery functionality?

Why the starter may not work after turning the key in the ignition. The main causes of starter malfunctions: bendix, traction relay, brushes, winding.

Purpose, design features, installation location of the fuel pressure regulator of an injection engine. Signs of RTD malfunctions, checking the device.

A relay regulator is installed on cars to maintain stable voltage from the generator. This element protects the battery from overcharging, extending the battery life. It is the breakdown of the generator voltage regulator relay that is one of the most common malfunctions of the vehicle’s on-board network.

Causes and possible consequences of the malfunction

The generator may not work for the following reasons:

malfunction of the voltage regulator (“pills”, “chocolates” in the slang of car enthusiasts);
wear (destruction) of brushes;
short circuit of the exciting winding (rotor);
breakdown of diodes (located in the horseshoe);
wear of bearings and bushings.

A faulty voltage regulator usually results in a lack of battery charge. In this case, the “battery” indicator light appears on the dashboard. The engine continues to run until the battery is discharged to approximately 8 - 9 volts.

During daylight hours, the battery charge may be enough for 30-50 kilometers, provided that the battery was well charged at the time the malfunction occurred.

If the output stages of the voltage regulator breakdown, a malfunction may occur due to an increase in the generator output voltage to 17 - 20 Volts. This recharges the battery. The consequence of overcharging is the process of boiling of the electrolyte. If signs of corrosion appear under the hood in the battery area, it is necessary to check the generator.

A breakdown of the diode bridge can occur when the battery is accidentally reversed (installing the terminals in the wrong polarity). Typically, diodes are punched in pairs in one arm. A faulty diode has a resistance close to zero. In this case, the stator winding of the generator operates in short circuit mode and becomes very hot.

Read also: How much lemon juice do you need to clean a washing machine?

After a few minutes of engine operation, the windings overheat, and a smell of burnt electrical wiring appears under the hood of the car. To avoid fire, the engine must be turned off and the generator checked.

Wear of the brushes leads to gradual failure of the generator. First, while driving, the charge indicator light on the dashboard begins to blink, then it begins to glow constantly. In many generator models, the brushes are changed together with the voltage regulator.

A short circuit in the generator windings can lead to a significant change in output parameters and overheating of the device.

Possible causes of failure of the regulator relay

Modern relay models have a relatively long service life. But some factors can lead to premature failure of the element, namely:

Low quality of the part itself.
The occurrence of a short circuit.
Mechanical damage to the part.

The problem may also be caused by water ingress.

On some generator models, replacement of the electronic regulator relay will be necessary if the brushes are worn out. Under normal conditions, the life of the voltage regulator exceeds 60,000 km.

Checking the windings

First you need to visually inspect the windings. If there are no visible defects, you should use a multimeter. First you need to do the following:

Remove the brush holder.
Disconnect the voltage regulator.
Clean the slip rings.
Diagnose the winding for defects.

The resistance measurement function on the multimeter should be activated. The measurement is taken between the slip rings and the stator. In normal mode, the value will be from 5 to 10 ohms.

Main symptoms of a malfunction

There are two main “symptoms” of a relay failure. This is an undercharge or overcharge of the battery. Also, a malfunction of a part can be determined by the dim glow of the headlights or by a change in their brightness when the engine speed increases.

If undercharged, the car will start with great difficulty. However, the manifestation of this “symptom” may not be related to the generator. Therefore, first of all, you should make sure that the battery is in good condition.

If the battery is overcharged, there is no doubt that the problem lies in the damaged relay. There are other possible causes of overcharging, but they are extremely rare. Overcharging may cause the battery to boil over. This can be determined by the decrease in the amount of electrolyte in the jars and the appearance of a white coating on the battery.

If you suspect that the battery is overcharged or undercharged, you should diagnose the generator.

Checking with a multimeter without dismantling

You can check the condition of the relay using a multimeter. In this case, the generator is not dismantled. Before starting diagnostics, it is enough to clean the battery terminals (their oxidation can affect the operation of the car and the readings of the measuring device).

The diagnostic procedure is as follows:

First you need to start the engine and let it warm up for a few minutes.
Next, you need to connect the multimeter probes to the battery terminals. The device displays a value of 20V.
After this, the voltage is measured. It should be within 13.2-14V. Such readings are considered normal for most cars.
Now you need to increase the engine speed (up to 2-2.5 thousand). The voltage should increase by about 0.2V.
If it exceeds 3,500 rpm, the multimeter should show 14-14.5V, but no more.

Serious deviations in the readings of the device indicate the presence of breakdowns of the relay regulator.

Checking generator components

The test begins with monitoring the functionality of the voltage regulator. To do this, the regulator is removed from the generator and a simple electrical circuit is created.

Any car interior light bulb can be used as an incandescent lamp. If voltage regulator 3 is working properly, lamp 6 should not glow at full power. When connected in parallel with the lamp (brushes) of a multimeter, its readings should be from 5.0 to 10.0 Volts. If the multimeter readings fall outside these limits, the regulator must be changed. The design of some generator models allows for the possibility of replacing the regulator without dismantling the device.

Next, check the exciting winding of the generator for breakdown. To do this, set the multimeter to resistance measurement mode at a limit of 200 kiloOhms. The probes are connected: black - to the commutator lamella, red - to the metal part of the armature. The resistance should be more than 100 kiloohms or higher than the upper limit of measurement, as shown in the photo.

The resistance between the lamellas (rotor windings) is usually 0.5 - 2 Ohms.

Checking the stator begins with checking the windings for breakdown. To do this, the red probe of the multimeter is connected to the metal part of the stator, the black probe is connected in series to the windings.

The resistance must be above the upper measurement limit. Then the resistance between the winding contacts is measured. They should differ by no more than 5%. The measurement limit of the multimeter is set to 200 ohms.

If the winding has an electrical breakdown, a short circuit of the turns or a break, it must be replaced. There are workshops that rewind stators and rotors.

To check the health of the diode bridge, the multimeter measurement mode is switched to the “diode” test. Then the diodes (their number on a horseshoe is usually 9) are sequentially “ringed” in forward and reverse connection. In the forward direction (black probe to the cathode) the resistance is 550 - 700 Ohms, when switched in reverse it is greater than the maximum measurement limit.

When the diodes breakdown, the resistance in all directions will be practically zero. This diode should be changed. The difficulty of replacing a diode lies in the fact that the diodes in generators are not soldered, but spot welded to ensure reliable contact at different temperature conditions.

A car generator is an important part of a car's electrical equipment. At the first sign of inoperability, it is necessary to check it using a multimeter.

Inside each car there is a miniature power station - a generator, which is responsible for generating electricity. If something breaks in it, the battery will start to work incorrectly. The result is a suddenly stalled engine. For some reason this always happens at the most inopportune moment. To avoid being left without a car somewhere in the wilderness, periodically check the generator voltage regulator.

Read also: Do-it-yourself Bosch hair dryer repair

How to test a relay with a lamp

On many modern cars, the relay is combined with brushes. In this case, you can check the regulator using an incandescent lamp. The procedure will be as follows:

To get to the part, you need to unscrew the mounting bolts and remove the terminals. The relay is located at the rear of the generator.
To check, you need to prepare a 12V light bulb with a socket, wires, a voltmeter, and a power supply (no more than 20V).
Next you will need to assemble the following circuit.

After connecting the light bulb, it should light up. At the same time, the voltage gradually increases. When it reaches 14.5V, the light should go out. If this happens later, it means the relay regulator is faulty.

When the voltage decreases, the lamp should light up again.

This test method can also be used for some models of regulators that are not combined with brushes.