Bench Testing: Rotor

WARNING: This page is about a different car, the 2003 Isuzu Rodeo Sport. However, it is still accessible from the selected car via links, so may be relevant.

Check the face of the slip rings for contamination and roughness. See Fig 1 . If found to be scored, dress with a fine sandpaper (#500 - 600). If found to be contaminated, clean with a cloth saturated with alcohol.
Measure the outside diameter of the slip rings. See GENERATOR SPECIFICATIONS .
Check resistance between slip rings, and replace if there is no continuity. See Fig 2 .
Check for continuity between slip ring and rotor core. If there is a continuity, replace the rotor assembly. See Fig 2 .

Fig 1: Identifying Rotor Components

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 2: Checking Rotor For Open Or Grounded Circuits

Courtesy of ISUZU MOTOR CO.