Rotor Test
- Remove rotor from alternator. Set ohmmeter to X1 scale. Measure resistance between rotor slip ring. Resistance should be 2.0-3.9 ohms. Replace rotor if resistance is not within specification.
- Set ohmmeter to X1000 scale. Connect one ohmmeter probe to either slip ring. Connect other probe to rotor shaft. Resistance other than infinity indicates rotor is shorted to shaft and must be replaced. Damaged slip ring terminals or solder touching rotor shaft can cause shorted condition.
NOTE:
Digital ohmmeter CANNOT be used for following test. Resistance measurements may differ slightly from specification, depending on ohmmeter used.