The main reasons for the lack of battery charging on the VAZ 2107

Theory “on fingers”: how everything works

On the VAZ 2107, devices can receive power from 2 sources. The first is the battery, the second is the generator. The battery supplies energy when the engine is turned off. It has a certain charge, consumed as needed. The generator produces electricity, but only if the rotor is spinning. That is, with the engine running.

Battery operation diagram: 1. Battery, 2. Negative diode, 3. Additional diode, 4. Generator, 5. Positive diode, 6. Stator winding, 7. Regulator, 8. Rotor winding, 9. Capacitor, 10. Mounting block, 11. Control lamp, 12. Voltmeter, 13. Ignition relay, 14. Lock.

The battery charge is used to start the engine. When the engine starts running, the battery energy is not consumed: the generator supplies all devices with it. A charge is also supplied to it to restore wasted energy. But if the battery is not charging, its own energy will be enough for a limited number of starts. The battery will then be completely discharged. And the car owner will have to solve the problem of how to start a VAZ 2107 if the battery is dead. After all, not everyone has “crocodiles” in their trunk, and not everyone will agree to share electricity with their battery.

Voltage regulator

And most importantly, the VAZ-2107 charging lamp is connected to the excitation winding through a voltage regulator. The latter allows you to maintain the voltage at the same level - within 13.6-14.2 V. The design of the regulator can be absolutely any, the following designs are distinguished:

1. Mechanical - work on electromagnetic relays.
2. Electromechanical - work on electromagnetic relays and transistor switches. A kind of combined scheme.
3. Electronic regulators - consist of a single crystal on which a switching circuit is made. Essentially, this is one large power switch that allows switching to maintain the required voltage level.

Indicator light

As can be seen from the diagram, the charging system involves a large number of components and each of them can cause poor charging or its absence. To monitor the battery charging process, the car's dashboard is equipped with a control light.

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If the system is in good working order, the control signal turns on after the factory. But when the engine enters operating mode, the VAZ 2107 battery charging light does not light up. This means that the battery's energy supply is replenished from the generator. At the same time, the needle on the voltmeter moves to the green sector.

Signs of a battery not charging:

• The VAZ 2107 battery charge arrow twitches.
• The control signal does not go out. In some cases, the VAZ 2107 battery light blinks.
• The voltmeter needle does not go to the green zone after starting the engine.
• When the engine is running, the voltage on the battery should remain around 13.9.
• The permissible deviation in any direction does not exceed 0.3 V. Undercharging of the VAZ 2107 battery within these limits is not yet dangerous.

A voltage drop to 12 V says: the generator is not charging! lamp is dimly lit - the battery is undercharged.

No charging: signs and reasons

If the voltage from the generator for some reason stops supplying the battery, it will be discharged in a few days. And in the event of a complete failure of the battery installation, you will have to provide the entire on-board network, including the ignition system, yourself. So she can work for no more than an hour.

Signs of no charge

Symptoms that the alternator is not charging the battery include:

• a constantly burning or intermittently turning on warning light on the dashboard;
• rapid battery discharge;
• reduction in the performance of individual electrical devices on the machine's on-board network.

Signal lamp

There is a special lamp on the dashboard of the “Seven” that indicates that the battery is not charging. If the generator circuit is operating in normal mode, the lamp lights only when the ignition is on until the power unit starts operating. It should go out after the engine starts. If it continues to light, most likely the battery is not charging.

It also happens that the control lamp turns on periodically. This is a sign that voltage is either not supplied to the battery at all, or is supplied inconsistently.

Battery drains quickly

If the generator or its circuit malfunctions, the battery will not receive the voltage necessary to charge it. In addition, she will have to power part of the car’s electrical equipment, consuming her own electricity. In such a situation, the battery will quickly run out. You will be able to understand this when difficulties arise in the process of starting the engine. Receiving insufficient energy, the starter will sluggishly turn the crankshaft flywheel or only “click” the traction relay.

Reduced electrical performance

Some electrical appliances will also help you understand that the generator is not operating normally. If you suspect a malfunction in the operation of the generator set, you can, for example, start the engine, turn on the headlights (if they have conventional incandescent or halogen lamps) and see how they shine. If the generator malfunctions, their brightness will be an order of magnitude lower, because the lamps are also designed for a certain rated current. A decrease in performance may also be observed at the heater fan. It will spin the blades noticeably worse. When it is turned on, the light from the headlights will be even weaker.

Reasons for lack of charging

There are few reasons for the battery not charging. These include:

• violation of the integrity (break) of the drive belt;
• belt loosening;
• a break in the wiring of the electrical circuit of the generator or severe oxidation of the connecting terminals;
• rectifier malfunctions;
• voltage regulator failure;
• a break in the generator windings or a short circuit.

Belt break

Although the belt is designed for 50 thousand km, it can break even after several days of use. Especially if there are defects in the pulleys of the device itself, the crankshaft or the pump. In itself, a break in the generator drive belt is not dangerous for the engine, but only if this malfunction is detected immediately. And the point here is not so much the lack of charging, but the pump stopping. If it stops working, the engine will instantly overheat. And this is already fraught with burnout of the cylinder head gasket with all the ensuing consequences. So if the warning light comes on or other symptoms of alternator malfunction occur, the first thing to do is check to see if the drive belt is intact. To do this, you need to stop the engine, open the hood and perform a visual inspection of the generator set drive.

Loosening the belt

The drive belt must have a certain tension. When the tension is weakened, it will slip on the crankshaft pulley, not providing the number of rotations of the generator rotor that is necessary to generate current with the required parameters. A sign of a loose belt is a characteristic whistle, which most often occurs when air humidity increases. When the belt slips, the warning light usually does not come on, but in some cases it may turn on for a while or blink.

Open circuit and terminal oxidation

The battery will not charge even if the integrity of the wires in the generator connection circuit is damaged. The battery charging circuit is quite simple: just one wire connects the positive terminal of the battery to terminal “30” of the generator set. It is through this that the voltage is supplied. The battery negative is connected to ground, to which the generator housing and the corresponding winding terminals are also connected. You just need to check for contact between the indicated points in the circuit.

Where to start checking

If the VAZ 2107 battery icon does not light up, the voltmeter gives normal readings, but the battery does not charge, which means there is no (or insufficient) contact at the terminals. Their severe oxidation can cause the voltage from the generator to the battery simply not to flow. Therefore, it is necessary to remove the terminals, thoroughly clean them, as well as the battery terminals, then reconnect the battery to the on-board network and check the functionality of the charging system.

In the case when the voltage on the VAZ 2107 battery is still below normal, you need to measure it at the output from the generator with the engine running. Is there a big difference between the readings on the terminal and on the battery? Try cleaning the contacts and checking the wire connecting the battery to the generator. Broken - requires replacement.

The next element that is checked is the generator drive belt. If it becomes loose, it will slip along the pulley, which is why the generator will not be able to generate the required amount of electricity. And although charging will be carried out (provided the circuit is in good condition), it will not be enough. At the same time, the engine is running, the voltmeter shows the norm. However, if the system is loaded a little more - for example, by turning on the headlights - then the voltage drops sharply. Then, if the battery charge on a VAZ 2107 disappears, this indicates that the tension belt is loose and slipping. The belt should be tightened; if it wears out during operation, replace it. But you can’t overtighten either: excess belt tension puts an overload on the pumps and generator bearings.

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The third component of the circuit that is checked during the initial diagnosis is fuse No. 10 (in the fuse box). It is he who is responsible for supplying voltage to the battery: the VAZ 2107 battery charging fuse has blown - the system will not work.

If everything is in order with the terminals, belt, fuse, the reasons for poor charging of the VAZ 2107 battery need to be looked for further.

How does the battery charge in a VAZ 2107?

To understand how the process of charging the “seven” battery occurs, you need to know the principle of operation of the generator and understand the connection diagram of these devices.

Design, drive and characteristics of the VAZ 2107 generator

A car generator set serves to provide electricity to the vehicle’s on-board network, as well as to recharge the battery when the power unit is running. Structurally, it consists of the following main elements:

• housings with windings (stator);
• armatures (rotor);
• current conversion module (rectifier);
• stabilizer (voltage regulator).

  
  The generator serves to provide electricity to the vehicle's on-board network.

The unit is driven by a belt from the crankshaft pulley.

Throughout its history, the “Seven” was equipped with two types of generating sets: 372.3701 and 9412.3701. They have the same design and operating principle, except that in unit 9412.3701 the fan blades are located inside the housing, and the rectifier module is located outside.

Table: main technical characteristics of VAZ 2107 generator sets

The performance of these devices differs greatly in terms of the amount of current produced and power output. Generator 9412.3701 is more productive. It is used in injection “sevens”, where the on-board network is supplemented by an electronic engine control system.

How does the VAZ 2107 generator set and the generator circuit work?

Without delving into the theory of electrical engineering, the generator functions as follows. When the key is turned in the ignition switch, the current from the battery through the relay and charge warning lamp is supplied to the exciting stator winding. At the same time, the crankshaft begins to rotate the rotor. During rotation of the armature, an electromagnetic field is formed in the phase windings, which induces an alternating current. Since all electrical devices on the on-board network are designed for direct current, the design of the installation includes a semiconductor rectifier module. The amount of voltage produced by the generator varies depending on the crankshaft speed. To stabilize it, a special regulator is used, smoothing out surges and dips and supplying the machine’s on-board network with a voltage as close as possible to the nominal one.

The electric current generated by the generator is supplied to the battery terminals to charge it.

Thus, when the engine is running, the generator converts the torque of the crankshaft into a direct current of 55 or 80 A (depending on the type of device) and a voltage of 13.9–14.5 V, necessary for operating electrical devices and charging the battery. Current is supplied to the positive terminal of the battery through terminal “30” and a separate wire, and the “ground” of the installation is connected to the negative terminal of the battery.

Video: how the generator works

What else to check

1. Voltage regulator;
2. Generator rectifier unit;
3. Diodes;
4. Generator for broken windings;
5. Generator brush assembly;
6. Contacts on the terminals of the generator, mounting block.

A malfunction of any of these elements leads to the fact that the charging system is inoperative and the VAZ 2107 battery is not charged.

Let's continue... Diodes are checked with a test light or multimeter. If one of them is broken, the entire rectifier will have to be replaced.

To check the stator winding you need the same device. The resistance between the fasteners of the rectifier unit is measured. If there are no contacts between them, you need to replace either the winding or the entire generator.

The generator itself often fails due to wear on the brushes. To check them, you need to remove the brush assembly and measure the length of the elements. If it is 5 mm or less, the brushes must be replaced.

Almost all of the above system components are replaced when they fail, since they cannot be repaired. Only some of the generator problems can be repaired, but this can only be done by a qualified auto electrician.

The worst thing is if problems with recharging occur while on the road. Without recharging the battery, it will eventually run out completely. And even if you manage to find the cause of the breakdown and eliminate it, you will no longer be able to start the engine with the starter. It will be possible to start a VAZ-2017 with a dead battery only from a tug or pusher.

More complex breakdowns

If, when the engine is running, the voltage in the on-board network is in the normal range, but when the load increases, it immediately drops, then we can say that the alternator belt is very loosely tensioned. Quite often, at low speeds, the belt even begins to whistle. It should be noted that with normal belt tension, the sag should be no more than 17 mm. Moreover, the force should be no more than 10 kgf. If the belt is very loose, it needs to be tightened. If tension cannot be achieved, a new one should be installed.

But you cannot tighten the belt too much - this will cause excessive load to be applied to the bearings. This will lead to damage to the bearings of the pump and generator. Quite often, the cause of loss of charging is a breakdown of one or more diodes of the rectifier bridge. It also happens that the rotor or stator winding breaks through. To check these elements, you need to completely disassemble the generator set.

What to consider when choosing a new battery

According to the passport, the battery is designed for 3-5 years of active use (in reality it turns out to be less). Therefore, over time, it becomes necessary to buy and connect a VAZ 2107 battery instead of a failed one.

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Choosing a battery for a VAZ-2107 car

When purchasing a new battery, you should consider a number of parameters and characteristics. Battery type: serviced and maintenance-free. The first option allows you to check and replenish the electrolyte level. This makes it possible to use the battery longer.

The next question is: what power will the battery on the VAZ 2107 be most efficient. Batteries with a capacity of 50–60 Ah are suitable for this model. However, given that modern cars are equipped with energy-intensive equipment, it is better to opt for more capacious batteries. In addition, carburetor VAZ models require more powerful batteries - they consume more energy when starting. In terms of dimensions, the VAZ 2107 requires power supplies with dimensions of 242*175*190 mm. The vast majority of samples available on the market fit them.

When choosing a battery, you should also take into account the place of residence of the owner of the “Seven”. For those who live in the south, you can purchase a less powerful battery. Northerners are advised to prefer a battery with a higher capacity: in the cold, the car starts with high energy consumption.

Trouble-shooting

The warning lamp and sensor (on-board voltmeter) show the presence of a charge, and the battery is flat, but checking with a multimeter shows a normal voltage of 13.6-14.2 V at the battery terminals. When a large load is turned on (for example, high beam headlights), the gauge arrow turns white scale sector.

The cause may also be a breakdown of one of the negative diodes, a burnout of one of the positive diodes of the rectifier, or a break in one of the stator phase windings. When the engine is not running, the negative diodes are checked: the “+” terminal of the battery is disconnected from the vehicle network and a test lamp is connected to it. Use the lamp leg to touch each of the three bolts securing the generator rectifier unit. If the lamp is on, the negative diode connected to the bolt is broken.

To check the positive diodes, connect the “+” terminal and disconnect the “-” terminal from the body, to which the test lamp is connected. Again, use the lamp leg to touch each of the three bolts securing the generator rectifier unit. Burning of the lamp also means breakdown of the positive diode. If you have a multimeter, simply measure the resistance of the diodes in the polarity in which the diode should be locked: for negative diodes “+” to the bolts, and “-” to the body, for positive diodes “+” to terminal “30” of the generator, and “ -" - to the bolts. A diode rectifier with a broken diode is completely replaced.

The break of one of the branches of the stator winding is checked by ringing them with a multimeter or a “tester” with a battery between the two bolts of the rectifier unit. The absence of contact of any winding with each of the two remaining ones indicates its breakage, and the generator must be repaired or replaced.

Check the generator brushes

Another reason could be wear on the generator brushes. The brush assembly from the PP is removed. If the brushes are less than 5 mm long, the unit is replaced with a new one. If the brushes are not worn out, they should be inspected for the possibility of distortion and “sticking” in the housing wells.

The charge lamp does not light up when the ignition is turned on. The charge sensor and other control devices do not work. The generator did not charge.

The cause of this malfunction is that fuse F10 (10 A) has blown. If nothing has changed after replacement, look for the reasons in the ignition lock or relay (if installed).

When the ignition is turned on, the control lamp does not light up. The charge sensor and other control devices are working. The generator does not charge.

The wire is disconnected from plug “61” of the generator and shorted to ground. If the lamp is on when the ignition is on, the generator excitation winding is faulty or there is no contact in the plug itself. The surfaces of the pins are cleaned, the bends of the plug connectors are pressed, and connected. It is checked again and if the charge lamp does not light up again, the plugs Ш5-Ш10 of the mounting block and the pins in the connector of the block with the instrument panel are cleaned. If there is no result, then the lamp itself has burned out. To replace a light bulb, the instrument panel is removed, the socket is removed from behind the panel, and the lamp is changed.

The battery light comes on when the ignition is turned on. When the engine is idling, the charge lamp lights up dimly, charging disappears or there is no charging at all.

The reason may be poor contact of the pin of the wire connection block to the instrument panel. It is attached with a rivet and often oxidizes. If you solder it to the board track, this problem is eliminated. Also, loose contact at the connection points along the wire path from the shield to plug “61” of the generator gives the same symptoms.

To check the excitation winding for an open circuit, use a multimeter probe to touch the rotor rings with the brush assembly removed - the working winding shows a slight resistance. When one probe touches the ring and the other touches the shaft or rotor housing, check for a winding short to ground. To check the voltage regulator relay, connect the “+” battery to the top contact, and “-” to the left one, and measure the voltage on the brushes. It should be 12 V. If not, the relay must be replaced.

Confronting attackers

Due to the fact that the battery is not cheap, the issue of protecting the VAZ 2107 battery from theft is quite acute. It’s not difficult to open the hood of a “classic,” which is why thieves are keeping a close eye on the “Sevens.”

Experts offer several options for preventing theft.

• Secure parking or secure garage.
• installation .
• Installation of the hood lock. Let’s be clear right away: few people take this step. Welding work is required, the appearance deteriorates, and it is quite easy for a professional to pick the lock.
• Take the battery with you. Labor-intensive, inconvenient, but effective. On the other hand, if the car is left for a short time, it is defenseless: they can even remove the battery in a supermarket parking lot.
• Reliable battery fixation. Almost the most popular method. The fasteners are secured with a secret that prevents dismantling and makes theft difficult. In combination with an alarm it is a very effective technique.

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But all experts agree that the most reliable protection for the VAZ 2107 battery against theft is comprehensive. A combination of multidirectional measures will give the best results!

Generator repair

If the generator set has been dismantled and problems are found in its component parts, work should be done to replace them. Repair of the VAZ-2107 generator is carried out as follows:

• fix the impeller with a screwdriver;
• unscrew the fixing bolts;
• remove the pulley parts;
• unscrew the bolts securing the cover. Take out the pin;
• use a hammer to knock off the stator cover;
• remove the bushing located under the front cover, which also needs to be removed;
• knock out the rotor with gentle blows of a hammer;
• unscrew the nuts securing the rectifier to the winding terminals;
• unscrew the nut with the abbreviation “30” and remove the washer;
• replace structural elements;
• assemble the device;

This completes the work of replacing generator parts.

Video repair of VAZ 2107 generator

For more information about generator repair, watch the following video:

Blown fuse

A failed dashboard light may be caused by a blown fuse. In this case, several devices usually fail at once. If such a symptom appears, you just need to check the fuse. It is located in the mounting block.

Mounting fuse block VAZ 2107

You can find it using the diagram on the block cover. To check, the fuse is removed from the mounting block. The easiest way is to install a known good fuse. If this is the reason, then the light should light up when the ignition is turned on. You can also check the fuse by measuring the resistance with a multimeter.