Your Oldsmobile alternator, like most alternators, are made of the following parts: a rotor, stator, voltage regulator and two internal fans. Your Oldsmobile alternator's function is to run the car's electrical system and recharge the battery, enabling the battery to start your car. The alternator is driven by belts in the engine, where it produces an alternating current, which is converted internally to 12 volts direct current by the diode bridge or rectifiers. Most alternators now use internal voltage regulators to maintain the proper system voltage, which ranges from 12.6-14.5 volts. The alternator has two terminals: the positive output terminal of the alternator, and the alternator housing, which is the alternator's negative (-) terminal. The regulator acts as the 'brains' of the car's charging system; it monitors both battery and stator voltages and adjusts the output of the alternator accordingly. When one of these parts of the Oldsmobile alternator begins to fail, it is recommended that you replace the Oldsmobile alternator as a unit, instead of trying to diagnose and replace each part as they fail. One sign of failure: the charge indicator light (or 'idiot light') comes on, although that may also represent a faulty fuse in the system, and not a bad alternator. You can check the voltage at the alternator connector and other connections in your electrical system with a voltmeter to measure the voltage. Or, listen for a distinctive grinding noise that comes from the alternator's bearings. All of these may be signs that your Oldsmobile alternator has been finally been worn out.