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Rectifier Shorted Or Grounded & Stator Grounded Test

  1. Set ohmmeter on "x1" scale. Connect one probe to alternator BAT terminal and other probe to STA terminal (rear blade terminal).
  2. Reverse ohmmeter probes and repeat test. Ohmmeter should read about 6 ohms in one direction and infinity when probes are reversed. Reading in both directions indicates bad positive diode, grounded positive diode plate, or a grounded BAT terminal.
  3. Perform same test using STA and GND terminals of alternator. Readings in both directions indicate either bad negative diode, grounded positive diode plate, or grounded BAT terminal.
  4. If no needle movement is indicated in one direction, but high resistance (considerably more than 6 ohms is indicated) in the other direction, bad connection exists in alternator circuit.
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