Probably everyone noticed a red small box on the dashboard, which indicates the battery. And we all know that if you turn the key in the ignition lock, this lamp lights up, but immediately goes out when the motor is started. When the driver inserts the key and turns it into the ignition lock, automatic self-test is carried out in fact all the engine systems, after successful diagnostics, the indicators are extended, which means the serviceability of the entire system. The same thing happens with the battery, when everything is in order with it, the bulb goes out, but if with a battery problems, the indicator will not stop burning.

Charging the battery from the generator as it happens

Even, even a novice car enthusiast, knows that the battery interacts with the generator and after starting the motor, the battery switches to continuous recharging mode. When the motor turnover rises, voltage increases at the generator outlet.

To prevent the rotor excitation in the circuit, a small relay controller is mounted, the main task of which is to reduce the current to a normal level, regardless of the number of motor revolutions. Accordingly, the voltage is maintained at the desired level. The battery lamp lights up when the charging is missing from the generator.

Battery light burns, reasons

There are a number of reasons for which the battery lamp does not go out when the motor is started:

1. Bad stretch of the generator, slipping or critical belt wear. Schedule (wear) generator bearing.
2. The relay regulator was faced or a diode bridge.
3. Fuse overwhelmed or bad contact.
4. The generator excitation chain was cut off, a strong wear of the brush holders or the generator brushes.
5. Bad contact on the mass of the mass, on the output of the generator or on the terminals of the battery.
   
6. The ignition switch was worn out, however, in this case, several light bulbs will be lit.

Tools Assistants for Diagnostics

If the battery light is on when the motor is working, it is not necessary to join it, you need to open the hood and check the voltage on the terminals of the battery. If charging is received on the multimeter, the voltage must be 13.5 - 14.3 V. When there is no charging, the voltage will be significantly lower - about 12 V.

To solve the problem, you will need the following tools:

1. Two screwdrivers - cruciform and flat.
2. Knife, pliers and "emery" to clean the contacts.
3. Multimeter.
4. "Header" - a light bulb at 12 V.
   

Battery light burns, the most frequent causes and ways to eliminate them

Option first. If the onboard voltmeter shows the charge, the battery lamp does not burn, the battery is completely discharged, and the multimeter demonstrates 12 V on the battery terminals.

It is necessary to clean the high voltage and terminals and terminals, after which the voltage measure again. If this does not give any result, you should check the voltage to the "30" terminal of the generator. The first multimeter electrode must be connected to the generator terminal, and the second to the mass. In this case, the voltage may be slightly higher than on the battery, then the "30" terminal should be cleared. If necessary, change the wire moving from the generator to the battery.

Option second. The voltmeter on the instrument panels and the bulb indicate charging, but the battery was discharged. At the same time, the voltage on the battery is normal, however, when loading (headlights, a signal, and so on), the charge arrow is twisted into the leftmost position. The reason is the weak tension of the generator belt, or the problem with the bearing either with pulley.

In addition, the cause of this situation may be a breakdown in the winding of the stator or the breakdown of one from the diodes. You must turn off the ignition and using the multimeter to check the diodes. If you find a breakdown, you should replace.

It will not be superfluous and checking the generator brushes. To do this, check the length of the brushes - it should be at least five millimeters. Otherwise, brushes are subject to replacement.

Option third. If, after turning the key, the battery lamp is not lit, the charge sensor does not work, and the battery does not charge, most likely the reason lies in the fuse brave. It is denoted by "F10", and its nominal is 10 AMP. This fuse should be replaced, however, if you did not see the result, the reason is most likely lies in the ignition relay or the castle itself.

Option fourth. There is no charging after turning the key, the battery lamp does not burn, but all the devices function.

With "61", the generator terminals should be removed, then connect it to minus. If, after this operation, the bulb caught fire, the cause is the excitation winding of the generator.

In addition, the reason may be bad contacts in the connector. It is necessary to clean and check it well. If there is no result, most likely a light bulb burned. If it's not in the lamp (burning with interruptions and dim), then other indicators will also burn with interruptions or dimly.

Fifth option. The lamp after starting the engine does not go out, the charge is intermittent or missing. As a rule, the cause of such behavior is bad contact of the wire with the connector on the instrument panel.

Tips of professionals

After all the above operations, you need to check the relay controller, give voltage to contacts. Also, it is worth checking the voltage on the brushes - the relay is properly if it is 12V, otherwise it must be replaced.