Section 252 (Charging System - Generators & Regulators): Generator: Inspection

2004 Toyota Celica GT, StandardSECTION Inspection
WARNING: This page is about a different car, the 2002 Toyota Celica. However, it is still accessible from the selected car via links, so may be relevant.
  1. Inspect Voltage Regulator 
    1. Using an ohmmeter, check the continuity between terminals F and B.
      1. Standard: 
      2. When the positive and negative poles between terminals F and B are exchanged, there is continuity in one way but no continuity in another way. 

      If the continuity is not as specified, replace the voltage regulator.

      Fig 1: Checking Continuity Between Terminals F & B
      G01053512Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using an ohmmeter, check the continuity between terminals F and E.
      1. Standard: 
      2. When the positive and negative poles between terminals F and E are exchanged, there is continuity in one way but no continuity in another way. 

    If the continuity is not as specified, replace the voltage regulator.

    Fig 2: Checking Continuity Between Terminals F & E
    G01053513Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Inspect Rotor For Open Circuit 

    Using an ohmmeter, check that there is continuity between the slip rings.

    1. Standard resistance: 
    2. MT 2.7 - 3.1 ° at 20°C (68°F) 
    3. AT 2.1 - 2.5 ° at 20°C (68°F) 

    If there is no continuity, replace the rotor.

    Fig 3: Checking Continuity Between Slip Springs
    G01053514Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Inspect 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 4: Inspecting Rotor For Ground
    G01053515Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. Inspect Slip Rings 
    1. Check that the slip rings are not rough or scored.

      If rough or scored, replace the rotor.

    2. Using a vernier caliper, measure the slip ring diameter.
      1. Standard diameter: 
      2. 14.2 - 14.4 mm (0.559 - 0.567 in.) 
      3. Minimum diameter: 
      4. 12.8 mm (0.504 in.) 

    If the diameter is less than minimum, replace the rotor.

    Fig 5: Measuring Slip Ring Diameter Using Vernier Caliper
    G01053516Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. Inspect Stator (Drive End Frame) 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 6: Checking Continuity Between Coil Leads
    G01053517Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. Inspect Stator (Drive End Frame) 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 7: Checking For No Continuity Between Coil Lead & Drive End Frame
    G01053518Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. Inspect Exposed Brush Length 

    Using vernier calipers, measure the exposed brush length.

    1. Standard exposed length: 
    2. 9.5 ~ 11.5 mm (0.374 ~ 0.453 in.) 
    3. Minimum exposed length: 
    4. 1.5 mm (0.059 in.) 

    Fig 8: Measuring Exposed Brush Length Using Vernier Caliper
    G01053519Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If the exposed length is less than minimum, replace the brush holder assembly.

  8. Inspect Positive Rectifier Holder 
    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 9: Inspecting Positive Rectifier Holder
    G01053520Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  9. Inspect Negative Rectifier Holder 
    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 10: Inspecting Negative Rectifier Holder
    G01053521Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  10. Inspect Front Bearing 

    Check that the bearing is not rough or worn.

    Fig 11: Checking Front Bearing
    G01053522Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  11. If Necessary, Replace Front Bearing 
    1. Remove the 4 screws, bearing retainer and bearing.
      Fig 12: Locating Screws For Front Bearing Replacement
      G01053523Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using SST and a press, press out the bearing.

      SST 09950-60010 (09951-00350) 09950-70010 (09951-07100)

      Fig 13: Pressing Bearing Out Using Socket Wrench
      G01053524Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Using SST and a press, press in a new bearing.

      SST 09950-60010 (09951-00530) 09950-70010 (09951-07100)

    4. Install the bearing retainer with the 4 screws.
      1. Torque: 
      2. 3.0 N.m (31 kgf.cm, 27 in.lbf) 
      Fig 14: Pressing Bearing Out Using Socket Wrench
      G01053525Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  12. Inspect Rear Bearing 

    Check that the bearing is not rough or worn.

    Fig 15: Inspecting rear Bearing
    G01053526Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  13. If Necessary, Replace Rear Bearing 
    1. Using SST, remove the bearing cover (outside) and bearing.

      SST 09820-00021

      NOTE: Be careful not to damage the fan.
    2. Remove the bearing cover (inside).
      Fig 16: Displaying Bearing Cover Removal (Outside)
      G01053527Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Place the bearing cover (inside) on the rotor.
      Fig 17: Locating Bearing Cover (Inside)
      G01053528Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Using SST and a press, press in a new bearing.

      SST 09820-00031

      Fig 18: Pressing In New Bearing
      G01053529Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Using SST, push in the bearing cover (outside).

      SST 09285-76010

      Fig 19: Pushing In Bearing Cover (Outside)
      G01053530Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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