Rotor Field Coil Test

NOTE: Alternator must be disassembled to perform this test.

1. Connect suitable ohmmeter leads across rotor slip rings. If resistance is 2-6 ohms, proceed to step 2. If resistance is not 2-6 ohms, replace rotor.
2. Place one lead of ohmmeter on slip ring and other lead on pole, then repeat test with other slip ring. If reading is infinite, proceed to step 3. If reading is not infinite, replace rotor assembly.
3. Clip one lead of ohmmeter to stator lead and other lead to stator frame. If reading is infinite, proceed to step 4. If reading is not infinite, replace stator.
4. Clip one lead of ohmmeter to one of the stator leads and the other lead to one of the other stator leads. Repeat test on remaining two stator leads. If resistance is not infinite at either lead, stator is satisfactory, refer to Brushes Test. If resistance is infinite at either lead, replace stator. Brushes Test