Check Engine

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The dash of a car is shown with multiple warning lights on.

Warning Lights 101: Class is in Session

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Told you we’d get to this one a little later. This is something of a catch-all warning lights that indicates one of several possible problems has arisen. In general, this light is tied to the body control module (BCM) in your vehicle, which is responsible for monitoring all sorts of different systems in your vehicle – everything from your lights to traction control. Unfortunately, that means it can be hard to tell exactly what needs work when you see this light.

If you are driving when this light comes on, then safely pull off the road and come to a stop where you won’t be in danger. Leave your vehicle running, in park, and step out to check all your lights and make sure they’re still working. If your lights are fine, that means it’s something else, and you’ll need to go to a service professional for a proper diagnosis. No matter what, don’t hesitate – this is a big one, so act immediately to keep your vehicle in a safe condition.

Steering Lock

This is part of theft-prevention systems in most vehicles, though you won’t find it in all older models. If you see this light, it means the steering wheel is locked and cannot be moved. For some vehicles, all you have to do to address this light is to insert your key into the ignition, and the steering wheel will once again move for you, others require more steps. If you see that this warning light is on when you first get into your car, then it might mean someone else was in there trying to move the wheel. Read more on

Airbag Indicator

If you see this warning light, then it usually means something is wrong with your vehicle’s airbag system. Exactly what the issue is, however, requires the use of proper diagnostic tools – so this isn’t something you can readily just spot yourself. Since your airbags are an intrinsic part of your vehicle’s safety system, this is another light that you need to respond to promptly. It might not be as critical as an issue with your engine, but a defective airbag can fail to protect you in a collision, or actually cause injuries when it deploys.

An airbag light is on on a black car dash.

Windshield Washer Fluid

In fairness, this is pretty far down on the list of critical issues that you need to address with absolute haste. However, if you see this light, then it means your windshield wiper fluid is low and needs to be filled. Remember that your windshield wiper fluid is one of those things you might not think about too often, but you want to know it’s there when you need it. Plus, you can use this as an opportunity to check other things, like your tire pressure, oil level, and battery life.

Headlight and Brake Lights

Depending on your vehicle, this might be one light or two different warning lights – your owner’s manual can tell you which. In either case, when you see this warning light come on, it means you need to check the lamps in your headlights or brake lights. This is pretty easy – start your vehicle, turn on your lights, make sure you’re in park, then get out and walk around your car to check your lights. Make sure you replace dimmed or burned out lamps as soon as possible – not only will this make you a safer driver in the evening, but help you avoid a costly ticket.

Catalytic Converter

This is a surprisingly specific warning light compared to some others, and a very helpful one. The catalytic converter is part of your vehicle’s exhaust system, which is responsible for breaking down toxic gases produced by your engine. If you see this warning light, then it often means your catalytic converter is overheating or not operating properly. Be sure to have your exhaust system checked out right away – a flaw in that system can be very dangerous if it is exposing you to gases from your engine.

Shift Lock

Also called a “press brake pedal” light (for reasons that will quickly become obvious) this is one of those warning lights that makes you feel a little foolish. If you see this light come on, then you need to push the brake down on your vehicle when you try to turn your ignition. Nothing is wrong; you’re just getting a bit ahead of yourself. In some vehicles, a similar light can indicate you need to push the clutch instead. Read more about this light on

Fuel Indicator

This is one that can really help you avoid a serious inconvenience, but don’t over-rely on it. If you see this warning light, then you are getting low on fuel and need to stop at the closest gas station you find. This is a bit of an infamous warning light due to some drivers relying on it to let them know when to get gas. Don’t Do This! Keep an eye on your fuel gauge and rely on it – this warning light might mean you have less fuel than you think, or it might malfunction and leave you stranded with an empty gas tank.

Oh, and this light will often have a tiny arrow with it, which points to the side of the vehicle your gas cap is on. Some cars also have a warning light to let you know when the cap is not secure.

A yellow fuel low warning light is lit up.

Seatbelt Reminder

This warning light is just there to remind you that you don’t have your seatbelt on. In a lot of modern vehicles, the light will be joined by a surprisingly loud “ding” that will echo menacingly throughout the cabin. Put your seatbelt on, and the light will go off. Not only will this help save your life in a collision, but your friends will thank you for not making them listen to the dinging.

Fog Light Indicator

While some warning lights are there to alert you to a problem, others help you keep track of what you’re doing as a driver. This indicator light lets you know that your fog lamps are currently illuminated. It’s simply a reminder so that you know to turn them off before exiting the vehicle, or when you no longer need them.

Security Indicator

This can be either a system warning light or a reminder, depending on what it’s trying to tell you. In general, a security indicator is connected to your vehicle’s security system, so it might be illuminated to let you know the system is on or that you need a key with the proper fob to start the vehicle. It can also let you know the security system is malfunctioning in some way so that you can take it to a shop for repair.

Cruise Control Indicator

This is another indicator light, like the fog light one. Rather than a warning light that something is wrong, this is there to remind you that you have cruise control engaged. As soon as you press the brake or otherwise disengage the cruise control system, the light will go off. In other words, this is just a good reminder for you as a driver. Autoblog helps explain this light as well.

Car Doors Ajar

These warning lights are there to remind you or alert you to the fact that one or more doors are currently open or not securely shut on your vehicle. In some cases, you might have lights that let you know which door specifically, or if it’s in the front or rear. Other times, there may just be one light that warns you about any of the doors. In most cases, you can fix this issue by safely opening and closing all your doors until it goes off.