Rotor Open Or Short Circuit Test
- Remove rotor from alternator. Set ohmmeter on "x1" scale. Connect one ohmmeter probe to each rotor slip ring. Reading should be 3-5 ohms. Higher reading indicates damaged slip ring solder connection or broken rotor wiring.
- Lower reading indicates shorted wire or slip ring. Replace rotor if damaged. Connect one ohmmeter probe to slip ring. Connect other ohmmeter probe to rotor core. Ohmmeter reading should be infinity.
- If ohmmeter reading is not infinity, rotor is shorted to shaft. Replace rotor. Damaged slip ring terminals or solder touching rotor shaft will cause shorted condition.