System Test
CHECK CHARGING CIRCUIT WITHOUT LOADNOTE: If a battery/alternator tester is available, connect the tester to the charging circuit as per the manufacturer's instructions.
(a) If a tester is not available, connect a voltmeter and ammeter to the charging circuit as follows:
Fig. 1 Connecting voltmeter & ammeter to charging circuit:
^ Disconnect the wire from terminal "B" of the alternator and connect it to the negative terminal of the ammeter.
^ Connect the test lead from the positive terminal of the ammeter to terminal "B" of the alternator.
^ Connect the positive lead of the voltmeter to terminal "B" of the alternator.
^ Connect the negative lead of the voltmeter to ground.
(b) Check the charging circuit as follows:
With the engine running from idling to 2,000 rpm, check the reading on the ammeter and voltmeter.
Standard amperage: Less than 10A
Standard voltage:
4A-GE: 13.9 - 15.1 V at 25°C (77°F)
13.5 - 14.3 V at 115°C (239°F)
4A-GZE: 13.7 - 14.8 V at 25°C (77°F)
13.2 - 14.0 Vat 115°C (239°F)
^ If the voltage reading is greater than standard, replace the IC regulator.
^ If the voltage reading is less than standard, check the IC regulator and alternator as follows:
Ground Terminal F:
with terminal "F" grounded, start the engine and check the voltage reading of terminal "B".
^ If the voltage reading is greater than standard, replace the IC regulator.
^ If the voltage reading is less than standard, check the alternator.
CHECK CHARGING CIRCUIT WITH LOAD
(a) With the engine running at 2,000 rpm, turn on the high beam headlights and place the heater fan control switch at "HI."
(b) Check the reading on the ammeter.
Standard amperage: More than 30 A
If the ammeter reading is less than 30A, repair the alternator.
NOTE: If the battery is fully charged, sometimes the indication will be less than 30A.