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Field Circuit Drain Test


Alternators W/Integral Regulator
Connect voltmeter negative lead to the alternator rear housing for all of the following voltage readings.
1. Turn ignition switch to the ``Off'' position, then connect voltmeter positive lead to the regulator ``F'' terminal screw. Battery voltage should be present.
2. If less than battery voltage is present, disconnect regulator electrical connector and connect voltmeter positive lead to connector I terminal. No voltage should be present.
3. If voltage is present, repair circuit between I lead and ignition switch. If no voltage is present, proceed to step 4.
4. Connect voltmeter positive lead to the connector S terminal.
5. No voltage should be present. If voltage is present, disconnect alternator electrical connector. Again, connect voltmeter positive lead to the regulator connector S terminal.
6. If voltage is still present, repair circuit between S lead and alternator connector. If no voltage is present, replace alternator rectifier assembly.