When checking, according to the degree of electrolyte density in the battery, the densimeter readings are compared with its tabular values.
Density, g/cm3 | middle lane | South of the country |
AB is discharged | 1,15 | 1,10 |
AB half discharged | 1,22 | 1,17 |
AB is charged | 1,26 | 1,22 |
The electrolyte density in all AB banks should be the same and differ by no more than±0.02 g/cm3 from one another. If the density of the electrolyte in adjacent banks differs sharply, then there is a short circuit in the battery and it is faulty.
Battery troubleshooting
Reason | Troubleshooting |
The output power is too low, the voltage drops too much | |
Battery low | Charge the battery |
Regulator voltage too low | Check and, if necessary, replace the relay-regulator |
Bad or oxidized contact | Clean the contacts, especially the lower part, and lightly coat with acid-protecting grease: tighten the fixing screws |
Poor ground contact between battery-engine-body | Check ground connection, if necessary, ensure this contact: replace oxidized or browned fastening screws with tin-plated screws |
Excessive battery self-discharge due to insufficient electrolyte purity | Replace battery |
Possible sulfation (gray-white plaque on the plates) | Charge the battery with a low current so that the plaque dissolves slowly. In the event that after repeated charge-discharge, the output power is still low, replace the battery |
The battery is worn out, the active mass falls out of the plates | Replace battery |
Insufficient battery power | |
Malfunction of the generator or wires | Check alternator and voltage regulator, repair or replace |
Loose V-belt drive, defective tensioner | Check tensioner, replace V-belt if necessary |
Load too high | Put a larger battery, it is also possible to use a more powerful generator |
Electrolyte too low | |
Recharge, evaporation (especially in summer) | Top up with distilled water up to the mark (with a charged battery) |
Electrolyte density too low | |
Battery low | Charge the battery |
The density of the electrolyte in one of the jars is significantly lower than in the others | Bank short circuit. Replace battery |
The density of the electrolyte in two adjacent banks is significantly lower than in others | The separating wall is leaking, which creates a conductive connection between the banks, discharging the plates. Replace battery |
Short circuit in the onboard circuit | Check electrical units |
When checking under load, fix the value of the voltage drop when starting the engine, the battery voltage should not fall below 8.0 V, at an electrolyte temperature of +20°C. Checking the battery with high currents must be carried out using the Bosch tester T.12.200.E at the service station and according to the instructions for the device. This test is currently the most reliable method for judging battery charge and physical condition (plate closure and sulfation).
Attention! AB is subject to spontaneous discharge during vehicle storage. Battery recharge should be done every 45-50 days.
It is possible to recharge the battery in a car only when the engine is not running. Remove battery before recharging «–» terminal for connecting the vehicle's on-board network.
If the car is put into storage for a period of more than 1 month, then it is necessary to remove it from the battery «–» tip of the car's onboard network. If the car is put into storage for a period of more than one and a half months, then it is necessary to remove the battery, charge it and store it in a cool room, but at a positive temperature. Stored batteries are recommended to be recharged every 3 months. Each discharge, especially a long one, shortens the life of the battery. The electrolyte level must be between the marks «MIN» And «MAX» on the AB. If the level is low, remove the plug and add distilled water.
The control charge of the battery must be at least 5 hours long using a charger of the type «Gossen CG 32» or «Siemens/Gossen VB 801». Full battery charging continues until the state of charge exceeds 80% of its capacity.