FixVault

Rotor Field

With rotor removed from alternator rear housing, connect ohmmeter to rotor slip rings; meter reading should be 3.5-4.5 ohms. A higher reading indicates a damaged slip ring solder connection or broken wire. A lower reading indicates a shorted wire or slip ring. Check rotor for grounds by connecting ohmmeter from slip ring to rotor shaft; no continuity should exist.

Fig 1: FIELD OPEN OR SHORT CIRCUIT TEST
G09353520Courtesy of FORD MOTOR CO.