- assistant;
- multimeter (in voltmeter mode with a measurement range of 15-20 V);
- technical stethoscope.
Sequence of execution
1. Prepare the car for work (see "Preparing the car for maintenance and repair").
2. Warm up the engine to operating temperature (at least 80°C).
3. Turn on all powerful consumers of electrical energy in the car (heated rear window, electric heater fan, high beam headlights, heated seats).
Note: We will do the rest of the work with an assistant.
4. By pressing the gas pedal and monitoring the engine operation using the tachometer, we maintain the engine crankshaft speed within 3000-3500 rpm.
5. Using a voltmeter, measure the voltage at the terminals of the battery. If the generator is in good working order, the voltmeter should show a voltage of at least 13 V.
Note: If the voltage is less than 13 V, the alternator drive belt may be loose, there may be a fault in the alternator circuit, the alternator voltage regulator may be faulty, the alternator brushes may be oily or worn out, or there may be other faults in the alternator itself
6. Turn off all electrical consumers, while the voltmeter should show a voltage no higher than 14.7 V.
Note: If the voltage is greater than 14.7 V, the voltage regulator is most likely faulty.
7. Using a stethoscope, we evaluate the condition of the generator bearings by the noise. A loud hum indicates wear of one or both bearings (the front bearing fails most often).
(The text is copied from the online resource: VazBook.ru)