The battery is discharged while the vehicle is parked
1. The anti-theft alarm system consumes a lot of current. multimeter (ammeter) measure current consumption. Repair or replace the anti-theft alarm system.
2. Leakage of current in the electrical equipment of the car. multimeter (in ammeter mode) measure the leakage current. Disconnecting car circuits one by one (taking out the fuses), we determine the faulty circuit with the highest leakage current. We replace the defective part or eliminate the short circuit in the power supply circuit of electrical equipment (see «Electrical equipment - checking the technical condition»).
Battery not charging (battery charge warning lamp does not go out after starting the engine)
1. Insufficient or worn drive belt. Check the condition and, if necessary, replace the accessory drive belt (see «Accessory drive belts - replacement»).
2. Low electrolyte level in the battery. Check battery condition (see «Accumulator battery»). In a low-maintenance battery, bring the electrolyte level to normal and charge. Replace the maintenance-free battery.
3. Insufficiently tightened or oxidized terminals on the terminals of the battery. Clean wire terminals and battery terminals from oxides (see «Battery - Maintenance»). After connecting the terminals, coat them and the battery terminals with a special compound or any grease.
4. The generator is faulty. Check the technical condition of the generator (see «Generator - check»). Repair or replace the faulty alternator.
5. Faulty voltage regulator. Check the technical condition of the generator (see «Generator - check»). Replace the faulty voltage regulator or alternator assembly.
6. Faulty battery charging circuit. Check and repair electrical circuit (see «Electrical equipment - checking the technical condition»).