Q: 2010 Honda Accord Crosstour - battery light is illuminated and there's a whining noise coming from the engine. Is this the alternator?

Hello.

The battery light is usually activated when the computer detects that the system voltage is low. The most common cause for this is a faulty alternator or battery. The alternator is the component that provides the power for the vehicle’s electrical system once the engine is started. If it goes bad or has an issue it may set off the light due to low voltage. In most cases a faulty alternator will eventually lead to a dead battery, and stalling, if the engine is running when the battery dies. The alternator is driven by the engine’s serpentine belt, which could be a possible explanation for the noise.

There are also cases where a bad battery can also cause the battery light to come on. The battery serves as a stabilizer for the electrical system, and can cause the light to come on if it fails or has an issue such as a bad cell, or poor connection. As there is the potential for stalling, and even leaving the vehicle stranded, I would recommend having a professional technician, such as one from YourMechanic, visit your location to determine what the exact cause of the illuminated battery light.