Preparing for the test
1. Before testing, check the following items:
- 1) The condition of the battery installed in the vehicle;
- 2) Tension of the generator drive belt.
Caution: The battery used to test the current produced by the generator must be partially discharged. When the battery is fully charged, the test cannot be performed due to insufficient load on the generator.
2. Turn off the ignition.
3. Disconnect the cable from the negative terminal of the battery.
4. Disconnect the wire from the generator terminal "B".
Caution: Connect the wires and ammeter probes very securely, as a large current will flow through the circuit.
5. Connect a 0-100 A DC ammeter in series between terminal "B" and the wire disconnected from the generator. Make sure the negative probe of the ammeter is connected to the wire disconnected from the generator.
6. Connect a voltmeter (0-20 V) between the generator "B" terminal and ground. Make sure the positive probe of the voltmeter is connected to the generator "B" terminal.
7. Connect the tachometer and the wire to the negative terminal of the battery.
8. Leave the hood open.
Examination
1. Check that the voltmeter scale is clearly visible to determine the voltage value. If the voltmeter shows a voltage of 0 V, this means that the electrical circuit connecting the generator terminal "B" and the negative terminal of the battery is not closed, the fuse link has burned out, or the connection to the ground is unreliable.
2. Start the engine and turn on the headlights.
3. Turn on the high beam headlights and the heater fan to maximum air flow. Briefly increase the engine speed to 2,500 min⁻¹ and read the values on the instruments, while the ammeter will show the current produced by the generator.
Caution: After the engine starts, the battery charging current decreases very quickly, so this check must be performed very quickly.
Check result
1. The ammeter readings must exceed the limit value. If the current value is less than the limit value and the wire connecting the generator output is normal, remove the generator from the vehicle and check it. Current limit: 63.0 A for 90 A generator.
- 1. The maximum current value is indicated on the plate attached to the generator body.
- 2. The current produced by the generator depends on the temperature and load. Therefore, to obtain the maximum current value, partially discharge the battery, first turning on the headlights of the car with the engine off. The maximum current value produced by the generator cannot be obtained if the generator or ambient air temperature is too high.
2. After completing the generator current limit test, idle the engine and turn off the ignition.
3. Disconnect the cable from the negative terminal of the battery.
4. Remove the tachometer, voltmeter and ammeter.
5. Connect the wire to the "B" terminal of the generator.
6. Connect the wire to the negative terminal of the battery.