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Alternator & Regulator: Description

Delco-Remy CS-121 61-amp and 85-amp alternators are used on Storm and Storm GSi models. No periodic maintenance of alternator is necessary. Alternator is non-serviceable and must be replaced if defective.

Unlike other alternators, the CS-121 alternator uses only 2 connections, battery positive "+" and "L" terminal to charge indicator bulb. Three other regulator terminals, "P", "I" and "S" are provided for optional use. Terminal "P" is connected to stator and may be connected externally to a tachometer or other device. Terminal "I" is connected internally to field positive and is used in service diagnostics. Terminal "S" may be connected externally to a voltage source, such as battery voltage.

Fig 1: Charging System Wiring Schematic
G91C02000Courtesy of GENERAL MOTORS CORP.