Note: This test is to determine the condition of the voltage regulator.
1. Check battery charge (battery must be fully charged) and alternator drive belt tension.
2. Turn off the ignition.
3. Disconnect a wire from the negative plug of the storage battery.
4. Connect the voltmeter: connect the wire «+» voltmeter to output «IN» generator, and the wire «-» voltmeter - to «mass» or «-» battery.
5. Disconnect the wire from the terminal «IN» generator.
6. Connect DC ammeter (measurement range 0-150 A) in series between output «IN» generator and disconnected wire. Make sure that «-» ammeter connected to the disconnected wire.
7. Connect a tachometer and a wire of the negative plug of the storage battery.
8. Turn on the ignition and check that the voltmeter shows battery voltage. If the voltmeter shows 0 V, there is an open circuit between the terminal «IN» generator and «+» battery.
9. Start the engine, turn off the lights and accessories.
10. Set the engine speed to 2500 rpm and read the voltmeter reading when the recoil current is 10 A or less.
11. If the voltmeter readings correspond to the nominal value, the voltage regulator is working. If the voltmeter readings differ from the specified values, either the voltage regulator or the generator is faulty.
Voltage regulation amount
Outside air temperature,°C | Rated voltage, V |
-20 | 14,2-15,4 |
20 | 14,0-15,0 |
60 | 13,7-14,9 |
80 | 13,5-14,7 |
12. After the end of the check, reduce the engine speed to idle and turn off the ignition.
13. Disconnect a wire from the negative plug of the storage battery.
14. Disconnect the voltmeter, ammeter and tachometer.
15. Connect the wire to the terminal «S (L)» generator. Connect the wire to the negative battery terminal.