Output Current Test
OUTPUT CURRENT TESTThis test determines whether or not the generator gives an output current that is equivalent to the nominal output.
PREPARATION
1. Prior to the test, check the following items and correct as necessary.
Check the battery installed in the vehicle to ensure that it is in good condition. The battery checking method is described in "BATTERY".
The battery that is used to test the output current should be one that has been partially discharged. With a fully charged battery, the test may not be conducted correctly due to an insufficient load. Check the tension of the generator drive belt. The belt tension check method is described in the section "COOLING"
2. Turn off the ignition switch.
3. Disconnect the battery ground cable.
4. Disconnect the generator output wire from the generator "B" terminal.
5. Connect a DC ammeter (0 to 150 A) in series between the "B" terminal and the disconnected output wire. Be sure to connect the (-) lead wire of the ammeter to the disconnected output wire.
NOTE: Tighten each connection securely, as a heavy current will flow Do not rely on clips.
6. Connect a voltmeter (0 to 20 V) between the "B" terminal and ground. Connect the (+) lead wire to the generator "B" terminal and (-) lead wire to a good ground.
7. Attach an engine tachometer and connect the battery ground cable.
8. Leave the engine hood open.
TEST
1. Check to see that the voltmeter reads as the same value as the battery voltage. If the voltmeter reads 0 V, and the open circuit in the wire between the generator "B" terminal and battery (-) terminal, a blown fusible link or poor grounding is suspected.
2. Start the engine and turn on the headlights.
3. Set the headlights to high beam and the heater blower switch to HIGH, quickly increase the engine speed to 2,500 rpm and read the maximum output current value indicated by the ammeter.
NOTE: After the engine starts up, the charging current quickly drops. Therefore, the above operation must be done quickly to read the maximum current value correctly
RESULT
1. The ammeter reading must be higher than the limit value. If it is lower but the generator output wire is in good condition, remove the generator from the vehicle and test it.
Limit value
63 A mm. - 90 A generator
77 A mm. - 11 0 A generator
84 A mm. - 120 A generator
NOTE:
- The nominal output current value is shown on the nameplate affixed to the generator body
- The output current value changes with the electrical load and the temperature of the generator itself. Therefore, the nominal output current may not be obtained. If such is the case, keep the headlights on to cause discharge of the battery The nominal output current may not be obtained if the temperature of the generator itself or ambient temperature is too high.
In such a case, reduce the temperature before testing again.
3. Upon completion of the output current test, lower the engine speed to idle and turn off the ignition switch.
4. Disconnect the battery ground cable.
5. Remove the ammeter and voltmeter and the engine tachometer.
6. Connect the generator output wire to the generator "B" terminal.
7. Connect the battery ground cable.