These cars don't have mechanical voltage regulators anymore. They are solid state and built into the brush block assy. The alternator has been replaced with the exact same problem occuring. I doubt that the rear defroster is the problem because this has been going on for a year noe, and you have to remember our moderate climate in CA. The defroster would only be used a few months per year, and we don't have the 100% humidity you have. I lived in Virginia for a few years. Besides as I said in my last post, the lady sold the car so we may never khow. Thanks for the input though.
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