A Guide to Common Dashboard Warning Lights

Knowing what these symbols mean can directly impact your (and your car's) safety.

By: Nick Yekikian

Like many things, cars are not perfect. It is fair to assume something is eventually going to break or stop working no matter what sort of car you buy, and no matter how reliable it is rumored to be. Lucky for you, your car's proverbial brain will figure out an impending problem before you do and send you a warning more often than not. There are sensors and warning lights in new cars that alert you to tire pressure levels and the washer fluid level. But do you know what all those little icons on the dashboard mean? If not, we've got you covered. We've put together this guide on 10 of the most common car warning lights.

Fog Lights

We'll start with a dash light that isn't technically a warning light. The fog light symbol looks a lot like the one used for the regular headlights, albeit with a squiggly line in front of it instead of three lines that look like beams. Not all cars come equipped with fog lights, though, so it's possible you'll never see this dashboard light during the course of vehicle ownership.

Low Tire Pressure

Modern cars come with tire pressure monitoring systems and the little exclamation point inside of a half-circle merely means one or more of your tires have low pressure. If you see this sign, don't freak out. Instead, find a place to stop and inspect your tires. I'd they look a bit low, carefully make your way to the nearest gas station to fill them with air. On most cars, this light will go away on its own after you've topped the tires off.

Engine Oil Warning Light

Cars have been able to monitor their engine's oil pressure for years now. If you've seen what looks like a gravy boat light pop up in your dash it means there's a problem with your engine oil pressure. Without sufficient oil pressure, the engine can't properly lubricate itself. That can lead to major mechanical problems—the engine could seize and leave you stranded. As a result, it's best if you get this checked out right away.

Check Engine Light

The check engine light means that one of the many sensors monitoring your car has noticed a problem with the engine. It can be anything from a spark plug fault to the failure of something major such as the intake manifold or low compression. Unless you're really handy, you should leave a fix like this to a mechanic you trust. Either way, if you see the check engine light on your dash, something's gone wrong and you shouldn't put off a trip to the shop. The sooner you can fix it, the better.

Traction Or Stability Control Light

Most cars with traction or stability control allow you to turn these functions off. If you see what looks like the rear view of an old sedan followed by some squiggly lines on the road behind it, then that means your stability control system is either partially or fully off. This means one of two things has happened here: Either you turned the function off because you wanted to do some sporty driving (turn it back on, you're not Lewis Hamilton) or the feature has failed altogether. It's safest to let the computer think about traction for you, so find a way to get it back on ASAP.

Coolant Level Warning Light

If you see a little thermometer pop up in your dash, that means your car is probably overheating. There are a number of things that could have happened, but the best thing to do is stop the car and wait a good long while for the engine to cool down by itself. Next, grab a rag, pop the hood, and use the rag to lift the lid of the coolant reservoir and check the coolant level. If your car is so hot the engine, coolant reservoir, or coolant tank is "smoking," then you might want to call a tow service.

Brake System Warning Light

In the event that you see an exclamation mark with a circle around it in your dash, that means something is wrong with your brakes. There may be a problem with brake components or the hydraulic fluid may need a top-off. Stop the car and call a tow truck as soon as you safely can. Driving without a fully functioning brake system is dangerous (not to mention totally nuts) and should be fixed as soon as possible.

ABS Sensor Warning Light

Although it is related to the braking system, the ABS warning light does not signal a failure of the physical brakes. Instead, this signals an issue with the anti-lock brake system. It's likely that if you stop too hard with this light on, then your car's brakes may lock up, which could make it a struggle to come to a full stop. It's best to take your car to a shop in this case, as ABS is one of the most important safety enhancements in cars since the seatbelt was invented.

Airbag Warning Light

All cars have airbags these days. It's federally mandated (as it should be), and sometimes you'll see an airbag warning light in your dash. This light can mean a number of things. It can indicate a problem with any number of items, including the sensors that detect crashes and deploy airbags in the event of an accident have failed. If this light pops up on your dash consistently, then it's time to take your car to a shop for a lookover.

Battery Light

If you see a little red battery on your dash, then that means you're currently powering your car on the battery alone. When the engine isn't on, the alternator isn't actively charging the battery. That means eventually you'll drain the battery and you'll likely need a jumpstart to get you going again. If this light is on while your car's engine is on, then it's typically a sign that the battery charging system isn't working. In that case, you're going to have to take your car somewhere to get the problem diagnosed.

Unlock Gear Selector Light

This green shoe is inside the usual symbol for brake-related items—a circle with small arcs at the three and nine o'clock positions that represent an old-time brake drum and shoes—and is found only on vehicles with automatic transmissions. It's telling the driver they need to step on the brakes to unlock the gear selector before moving it from the park position. Once a foot is pressed on the brake pedal, it should go out.

Low Fuel Light

If this light is illuminated, it's time to stop for fuel, as your vehicle is running low. In some vehicles, exactly when this light comes on is determined by a set amount of fuel remaining in the tank; in others, the car's computer will use fuel remaining and recent driving behavior to predict that you may run out of fuel soon. Finally, this function can occasionally be handled by a simple light rather than an icon.

Diesel Glow Plugs Active

This curlicue is specific to diesel-powered vehicles and indicates the glow plugs are active. The glow plugs are used to warm the air in the cylinder prior to ignition, as the metal internals can absorb the heat of the fuel/air compression cycle and cause a failure to start. (Diesels do not have spark plugs like gasoline vehicles and rely on the heat from compression to facilitate combustion.) Once this light turns off, you can start your vehicle. If it's blinking, there may be a malfunction in the glow-plug system.