Dash Lights: The Battery Light on Your Dashboard

Battery light
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Check your dash before you start the car and you'll see a light that looks like a little battery with a "+" and "-" sign on it. This is your battery or charging light. What should you do if it comes on while you're driving?

If your battery charging light comes on while you're driving, you should pull over as soon as it's safe. This light comes on when your alternator is not making electricity and the car is running off of battery power alone. You can drive a short distance on the battery, especially if you turn off most of your car's electrical items (like the radio, air conditioning, etc.), but there's no way to know how far you'll get before it dies.

If you see this light come on, it usually tells you one of two things: you'll either need to replace your alternator belt or the alternator. But not so fast! Before you do this, go ahead and check your battery connections. The light can come on even if your alternator belt is intact and your alternator is charging well, but your battery connections are keeping the electrical circuit from properly electrifying the car's systems. Even a bad ground wire can be enough to cause a poor charging situation and trigger the dreaded battery light to come on.

Sometimes cleaning the battery connections will fix the charging problem without costing you a penny, or at least not much more than a penny. Remember to always look into the least expensive repair option before you dive in for the big-ticket fixes. In the case of cleaning your battery terminals, an ounce of prevention really is worth a pound of cure. 

Why Do I Have a Battery Light?

Your car or truck is equipped with a large number of systems that are constantly checking to see what's going on inside the engine, or at the brakes, even inside your tires as is the case with a TPMS (Tire Pressure Management System). Lots of these monitoring systems involve your safety, so not only is the information stored inside your car's ECU (the main computer, or brain, in your car or truck), there is often a light on the dashboard that comes on to alert you that some sort of error has been discovered in a certain system, like the braking system or the charging system, for example. This is great because if you see a warning light come on that indicates something serious, you know to pull over safely and call a tow truck, even if nothing appears to be malfunctioning fully yet.

The bad news is that this little light, while really good at getting your attention, is really bad at telling you exactly what the problem is. That's why when you see a light like the Battery Light, you have to do a little research or have some beforehand knowledge to work with before you can decide what's wrong with the car, whether it's a big enough deal to stop on the side of the road and call for a tow, or whether you can keep on truckin' and fix it when you have more time.