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Q: Battery light

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Battery light came on. Car also shut off. But started right back up. Car battery had dead cell in it. Replaced battery. Had alternator checked, it's good. But battery light still comes on and still shuts off. What other thing can I do to fix the problem? My car has an automatic transmission.

A: Hello, thank you for writing in. The chargi...

Hello, thank you for writing in. The charging system is controlled by the PCM (powertrain control module). The module receives input information to keep the electrical system operating, if the voltage goes below 9.0 volts the light will come on and causes the module not to operate producing a stall condition. To test this, you have to have the issue happening at the time. There is test equipment that has to be used-- you can find information about that and servicing it in our article here. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect this light for you, and make or suggest any repairs as needed.

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