Charging System: Testing and Inspection
Generator Output Line Voltage Drop Test:
GENERATOR OUTPUT LINE VOLTAGE DROP TEST
This test determines the condition of the wiring from the generator "B" terminal to the battery (+) terminal (including the fusible link).
1. Be sure to check the following before testing:
- Generator installation and wiring connections
- Generator drive belt tension
- Fusible link.
- Abnormal noise from the generator while the engine is running.
2. Turn the ignition switch to the OFF position.
3. Disconnect the negative battery cable.
4. Disconnect the generator output wire from the generator "B" terminal. Connect a DC test ammeter with a range of 0 - 100 A in series between the "B" terminal and the disconnected output wire. (Connect the (+) lead of the ammeter to the "B" terminal. Connect the (-) lead of the ammeter to the disconnected output wire.)
NOTE: An inductive-type ammeter which enables measurements to be taken without disconnecting the generator output wire is recommended.
Using this equipment will lessen the possibility of a voltage drop caused by a loose "B" terminal connection.
5. Connect a digital-type voltmeter between the generator "B" terminal and the battery (+) terminal. (Connect the (+) lead of the voltmeter to the "B" terminal. Connect the (-) lead of the voltmeter to the battery (+) cable.)
6. Reconnect the negative battery cable.
7. Connect a tachometer or the scan tool.
8. Start the engine.
9. With the engine running at approx. 2500 r/min, turn the headlights and other lights on and off to adjust the generator load on the ammeter slightly above 30 A. Decrease the engine speed gradually until the value displayed on the ammeter is 30 A. Take a reading of the value displayed on the voltmeter at this time.
Limit: max. 0.3 V
NOTE: When the generator output is high and the value displayed on the ammeter does not decrease until 30 A, set the value to 40 A. Read the value displayed on the voltmeter.
In this case the limit becomes max. 0.4 V.
10. If the value displayed on the voltmeter is still above the limit, a malfunction in the generator output wire may exist. Check the wiring between the generator "B" terminal and the battery (+) terminal (including fusible link).
If a terminal is not sufficiently tight or if the harness has become discolored due to overheating, properly repair the problem and perform the test again.
11. After the test, run the engine at idle.
12. Turn off all lights and turn the ignition switch to the OFF position.
13. Disconnect the tachometer or the scan tool.
14. Disconnect the negative battery cable.
15. Disconnect the ammeter and voltmeter.
16. Connect the generator output wire to the generator "B" terminal.
17. Connect the negative battery cable.
OUTPUT CURRENT TEST
This test determines if the generator output current is normal.
1. Before testing, be sure to check the following:
- Generator installation and wiring connections
- Battery
NOTE: The battery used should be slightly discharged. The load needed by a fully-charged battery is insufficient for an accurate test.
- Generator drive belt tension.
- Fusible link.
- Abnormal noise from the generator while the engine is running.
2. Turn the ignition switch to the OFF position.
3. Disconnect the negative battery cable.
4. Disconnect the generator output wire from the generator "B" terminal. Connect a DC test ammeter with a range of 0 - 100 A in series between the "B" terminal and the disconnected output wire. (Connect the (+) lead of the ammeter to the "B" terminal. Connect the (-) lead of the ammeter to the disconnected output wire.)
WARNING: Never use clips to connect the line. Use bolts and nuts otherwise loose connections (e.g. using clips) may lead to a serious accident and personal injury because of the high current.
NOTE: An inductive-type ammeter which enables measurements to be taken without disconnecting the generator output wire is recommended.
5. Connect a voltmeter with a range of 0 - 20 V between the generator "B" terminal and the ground. (Connect the (+) lead of the voltmeter to the "B" terminal, and then connect the (-) lead of the voltmeter to the ground.)
6. Connect the negative battery cable.
7. Connect a tachometer or the scan tool.
8. Leave the hood open.
9. Check that the reading on the voltmeter is equal to battery voltage.
NOTE: If the voltage is 0 V, the cause is probably an open circuit in the wire or fusible link between the generator "B" terminal and the battery (+) terminal.
10. Start the engine, and turn the headlights on.
11. Switch the headlights to high beam, turn the heater blower switch to High, increase the engine speed to approx. 2,500 r/min, and read the maximum current output displayed on the ammeter.
Limit: 70% of nominal output current
NOTE:
- For the nominal current output, refer to the Generator Specifications.
- Because the current from the battery will soon drop after the engine is started, Step #10 should be carried out as quickly as possible in order to obtain the maximum current out-put value.
- The current output value will depend on the electrical load and the temperature of the generator body.
- If insufficient electrical load is used while testing, the specified level of current may not be output even though the generator is normal. In such case, increase the electrical load by leaving the headlights on with the engine off to discharge the battery before testing.
- The specified level of current also may not be output if the temperature of the generator body answer ambient temperature is too high. In such cases, allow the generator to cool before testing.
12. The reading on the ammeter should be above the limit value. If the reading is below the limit value and the generator output wire is normal, remove the generator from the engine and check the generator.
13. Run the engine at idle speed after the test.
14. Turn the ignition switch to the OFF position.
15. Disconnect the tachometer or the scan tool.
16. Disconnect the negative battery cable.
17. Disconnect the ammeter and voltmeter.
18. Connect the generator output wire to the generator "B" terminal.
19. Connect the negative battery cable.
Regulated Voltage Test:
REGULATED VOLTAGE TEST
This test determines if the voltage regulator is correctly controlling the generator output voltage.
1. Be sure to check the following:
- Generator installation and wiring connections
- Battery fully charged.
- Generator drive belt tension.
- Fusible link.
- Abnormal noise from the generator while the engine is running.
2. Turn the ignition switch to the OFF position.
3. Disconnect the negative battery cable.
4. Connect a digital-type voltmeter between the generator "S" terminal and the ground. (Connect the (+) lead of the voltmeter to the "S" terminal. Connect the (-) lead of the voltmeter to a secure ground or to the battery (-) terminal.)
5. Disconnect the generator output wire from the generator "B" terminal.
6. Connect a DC test ammeter with a range of 0 - 100 A in series between the "B" terminal and the disconnected output wire. (Connect the (+) lead of the ammeter to the "B" terminal. Connect the (-) lead of the ammeter to the disconnected output wire.)
7. Reconnect the negative battery cable.
8. Connect a tachometer or the scan tool. Check that the reading on the voltmeter is equal to the battery voltage.
NOTE: If the voltage is 0 V, the cause is probably an open circuit in the wire or fusible link between the generator "S" terminal and the battery (+) terminal.
10. Make sure all lights and accessories are off.
11. Stan the engine.
12. Increase the engine speed to approx. 2,500 r/min.
13. Read the voltmeter when the current output by the generator becomes 10 A or less.
14. If the voltage reading conforms to the value in the voltage regulation table, the voltage regulator is operating normally. If the voltage is not within the standard value, a malfunction of the voltage regulator or of the generator exists.