Regulator I and/or S Circuit Test

I and S Circuits

Jumper Wires:

1. Disconnect the wiring plug from the regulator. Connect a jumper wire from the regulator A terminal to the wiring plug A lead. Add a jumper wire from the regulator F screw to the alternator rear housing.
2. With the engine idling and the voltmeter negative lead connected to the battery ground terminal, connect the voltmeter positive lead to the S terminal and then to the I terminal of the regulator wiring plug. The voltage at the S circuit should read approximately one-half that of the I circuit. If voltage readings are normal, remove the jumper wires. Replace the regulator and connect the wiring plug to the regulator. Repeat the load test.
3. If no voltage is present, remove the jumper wires and service the faulty wiring circuit or alternator.
4. Connect the voltmeter positive lead to the positive battery terminal. Connect the wiring plug to the regulator. Repeat the load test.