Preparing for the test
1. Before testing, check the following items:
- the battery installed in the car must be fully charged;
- check the tension of the generator drive belt.
2. Turn the ignition key to the "OFF" position.
3. Disconnect the cable from the negative battery terminal.
4. Connect a digital voltmeter between the generator "S (L)" terminals and ground. Connect the positive probe of the voltmeter to the generator "S (L)" terminal.
5. Disconnect the wire from the "B" terminal of the generator.
6. Connect a 0-100A DC ammeter in series between the "B" terminal and the wire disconnected from the generator. Make sure to connect the negative probe of the ammeter to the wire disconnected from the generator.
7. Connect the tachometer and the wire to the negative terminal of the battery.
Examination
1. Make sure the voltmeter scale is clearly visible to determine the voltage value.
The voltmeter should show the battery voltage.
If the voltmeter shows a voltage of 0 V, this means that the electrical circuit connecting the "S (L)" terminal of the generator and the positive terminal of the battery is not closed, or the fuse link has burned out.
2. Start the engine and turn off all electrical consumers.
3. Increase the engine speed to 2,500 rpm and when the current decreases to less than 10 A, read the voltage value on the voltmeter.
Check result
1. If the voltage matches the required value, then the voltage regulator is working properly. If the voltage differs from the required value, then the voltage regulator or generator is faulty.
Voltage regulator temperature,°C | Voltage regulation, V | |
Generator 75 A | Generator 90 A | |
–20 | 14,2–15,4 | 14,3–15,2 |
20 | 13,9–14,9 | 14,1–14,7 |
60 | 13,4–14,6 | 13,5–14,4 |
80 | 13,1–14,5 | 13,3–14,3 |
2. After completing the generator current limit test, idle the engine and turn off the ignition.
3. Disconnect the cable from the negative battery terminal.
4. Remove the tachometer, voltmeter and ammeter.
5. Connect the wire to the "B" terminal of the generator.
6. Connect the cable to the negative terminal of the battery.