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Charging Systems: Generator: Inspection

  1. INSPECT ROTOR. 
    1. Check rotor for open circuit. Using an ohmmeter, check that there is continuity between the slip rings. If there is no continuity, replace the rotor.
      1. Standard Resistance:  2.2-2.4 Ω at 20°C (68°F)
        2. Fig 1: Checking Rotor For Open Circuit
        G03149823Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the rotor for ground. Using an ohmmeter, check that there is no continuity between the slip ring and rotor. If there is continuity, replace the rotor.
      Fig 2: Checking Rotor For Ground
      G03149824Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Check that the slip rings are not rough or scored. If rough or scored, replace the rotor.
    4. Using vernier calipers, measure the slip ring diameter. If the diameter is less than minimum, replace the rotor.
      1. Standard Diameter:  14.2-14.4 mm (0.559-0.567 in.)
      2. Minimum Diameter:  12.8 mm (0.504 in.)
        3. Fig 3: Measuring Slip Ring Diameter
        G03149825Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. INSPECT STATOR (DRIVE END FRAME). 
    1. Check the stator for open circuit. Using an ohmmeter, check that there is continuity between the coil leads. If there is no continuity, replace the drive end frame assembly.
      Fig 4: Checking Stator For Open Circuit
      G03149826Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the stator for ground. Using an ohmmeter, check that there is no continuity between the coil lead and drive end frame. If there is continuity, replace the drive end frame assembly.
      Fig 5: Checking Stator For Ground
      G03149827Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. INSPECT BRUSHES.  Using vernier calipers, measure the exposed brush length. If the exposed length is less than minimum, replace the brush holder assembly.
    1. Standard Exposed Length:  9.5-11.5 mm (0.374-0.453 in.)
    2. Minimum Exposed Length:  1.5 mm (0.059 in.)
      3. Fig 6: Measuring Brush Length
      G03149828Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. INSPECT RECTIFIERS (RECTIFIER HOLDER). 
    1. Check the positive (+) rectifier.
      1. Using an ohmmeter, connect one tester probe to the positive (+) terminal and the other to each rectifier terminal.
      2. Reverse the polarity of the tester probes and repeat step (a).
      3. Check that one shows continuity and the other shows no continuity. If continuity is not as specified, replace the rectifier holder.
        Fig 7: Checking Positive Rectifier
        G03149829Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the negative (-) rectifier.
      1. Using an ohmmeter, connect one tester probe to each negative (-) terminal and the other to each rectifier terminal.
      2. Reverse the polarity of the tester probes and repeat step (a).
      3. Check that one shows continuity and the other shows no continuity. If continuity is not as specified, replace the rectifier holder.
        Fig 8: Checking Negative Rectifier
        G03149830Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. INSPECT BEARING.  Check the bearing is not rough or worn. If necessary, replace the bearing. (See REPLACEMENT ).
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