Stator Test

To check for ground, connect one ohmmeter lead to any stator lead. Connect remaining ohmmeter lead to stator frame. Ohmmeter reading should be infinity. See Fig 1 .
Delco CS series alternators have delta stator windings and cannot be tested for short or open circuits with ohmmeter. A noticeable discoloration anywhere on the stator usually indicates stator failure.

Fig 1: Bench Testing Stator For Grounded Circuits

Courtesy of GENERAL MOTORS CORP.

NOTE: Some digital ohmmeters cannot be used to check diodes in rectifier bridge. Consult ohmmeter manufacturer to determine ohmmeter capabilities.