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Q: Charning issues, new battery and alternator

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I've recently had the battery and alternator replaced with new ones on my car. Despite that, it seems to have some problems with charging. The voltmeter would go into the red zone each time I had the headlights turned on along with the wipers and the heat. The charging is normal when everything is turned off. Why is this happening?

Hello there. There are a few potential causes for why the car would have charging faults even after the alternator is replaced. The most common would be the battery cable, shorted harness, battery, or a failed alternator. The first thing a technician will do is to check for charging voltage and the alternator output. If the alternator output is below spec. It would be bench tested to rule it out as the fault before any more diagnosis is performed. A qualified technician, such as one from YourMechanic, will be able to perform a diagnosis on the charging issue and let you know what repairs or adjustments are needed.

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