LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Geo >> 1994 >> Prizm Base, Standard >> Repair and Diagnosis >> Electrical >> Charging Systems >> Alternator & Regulator >> Bench Testing >> Rotor Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Rotor Test

  1. Using an ohmmeter, check for continuity between rotor and slip rings. See Fig 1 (STEP 1). If continuity exists, replace rotor.
  2. Check for continuity between slip rings. See Fig 1 (STEP 2). If continuity does not exist and resistance is not 2.8-3.0 ohms, replace rotor.
  3. Measure diameter of both slip rings. If either slip ring diameter is less than .504" (12.8 mm), replace rotor. If slip rings are scored or rough, replace rotor.
Fig 1: Testing Alternator Rotor (Nippondenso)
G91H02012Courtesy of GENERAL MOTORS CORP.
scientia non olet · About LEMON Manuals