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Q: High voltage alternator

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The battery in my car was bonkers. I found out the alternator was working at 17 volts. Now all of the sensors in the car are on when the car is moving. Even the engine revs high. Is the alternator causing these things to happen? What should I do?

Most alternators have a voltage regulator integrated within them. This voltage regulator is responsible for making sure that the battery is charged right around 14 volts. If your alternator is producing 17 volts, it is almost a certainty that the voltage regulator within has failed.

I would recommend having your alternator replaced by a qualified technician to ensure that no other electrical problems result from the overcharging of your battery. If the battery continues to be overcharged for a long period of time, the other electronics of the vehicle may show signs of damage as a result of this.

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