When a light comes on and it’s shaped like a battery, it’s easy to assume your battery has gone bad. But that’s not always the case. That red light on your dash is actually known as your charging system – or voltage – warning light. When it comes to starting and powering your vehicle, your battery is only one piece of the puzzle. Let’s take a look at your starting and charging system, and see what’s really setting of that warning light.
When you turn your key in the ignition, you’re completing a circuit between your vehicle’s battery and starter motor. The battery provides power to the starter motor which – in turn – gets the motor running. Your battery does not have enough reserve energy to continue to power your vehicle though. Your main power source is actually your alternator – or generator in older vehicles.
As the main pulley on your engine rotates, it turns your alternator belt. The belt rotates the pulley on your alternator which – in turn – spins the internals of the alternator. Using a series of magnets and metals, the spinning generates electrical power. Power generated by your alternator – first – powers your engine to keep it running, and – second – returns to your battery to recharge it.
If the charging system (primarily your battery and alternator) drops too low during operation, it will trigger the light to inform you that the charging system is not working properly.
If you happen to see that light, don’t panic. Get your battery and alternator tested – most auto part stores do this for free! And make sure you check out your battery terminals for corrosion and your belt for wear before you consider dropping hundreds of dollars on other repairs.