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Testing Alternator Output With Regulator Inoperative

  1. Disconnect alternator harness connector. Unscrew molded cover from rear of alternator. Link together regulator negative terminal and "F" terminal. Connect an external test circuit as shown in lower half of illustration.
    CAUTION: Be aware of proper connections to avoid reversed polarity.
  2. NOTE: Variable resistor across battery terminals must not be left connected any longer than necessary to complete the test.

    Start engine and run at 800 RPM (1500 alternator RPM). The test circuit bulb should now be out.

  3. Increase engine speed to 3200 RPM (6000 alternator RPM) and adjust variable resistance until voltmeter reads 14 volts. Ammeter reading should then be approximately specified rated output. If obvious variance from specifications is encountered, alternator necessitates removal and overhaul or replacement.
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