The regulator/brush pack can be replaced in these alternators.

If it does not have 4 Zone climate control the part is not too expensive if you can find a good price on it.

4 Zone climate runs the price up a lot.

Doubt running the alternator without a load will hurt the diodes, it is more likely to cause havoc to the modules in the car.

Diodes are pretty robust when they have to handle close to 200 Amps.

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2008 4.8i Black with Tabacco. Black Y-spoke wheels and shadowline trim.