> On Wed, 21 Mar 2007 13:58:21 -0600, wrote:
>
>
>
>>Something is definitely wrong. It could be the voltage regulator, which is
>>internal to GM alternators I am familiar with. I would check visually for
>>any
>>obvious wiring problems, then take the alternator in for testing...or, just
>>take the car to a competent mechanic and let him fix it for you.
>
>
> It *is* the voltage regulator. No other component is responsible for voltage
> regulation.
>
>

Well....... Not entirely true. It can also be something like an alternator rotor with an internal short to ground. On many alternators, the regulator works by varying the effective resistance that is in series with the ground return from the rotor, with battery voltage always being available to the other terminal of the rotor. If a short to ground develops in the rotor, the alternator will charge without regulation.