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Rectifier & Stator Circuit

  1. Adjust ohmmeter to the x1 scale. Place ohmmeter probe on alternator BAT terminal. Place remaining probe on STA terminal. Note reading. Reverse probes and note reading.
  2. Perform same test procedure using STA and GRD terminals. An ohmmeter reading in both directions indicates defective negative diode, grounded stator, stator terminal, grounded positive diode plate or BAT terminal.
  3. There should be an infinite reading in one direction and a low reading in the other direction. A low reading of approximately 6 ohms should be obtained in one direction.
  4. An ohmmeter reading in both directions indicates defective positive diode, grounded diode plate or BAT terminal.
  5. Infinite reading with probes in one direction and no reading or excessive resistance in other, indicates bad connection on stator terminal and stator bolt head.