If you’ve ever had a check engine light come on in your vehicle, you know the fear and annoyance it can strike to your heart and wallet. You might be aware of this light if you have ever tried to get a smog test with it illuminated – it is grounds for automatic disqualification, and usually requires a replacement of an air fuel ratio sensor or oxygen sensor. We’re going to explain a little about what this light is, what the light means, and what you can do if it comes on in your car.
Modern check engine lights, or malfunction indicator lamps, are in place to tell the vehicle owner of an issue with the engine. All cars made in the last few decades come with an engine monitoring system in place called an OBD-II . OBD stands for On-Board Diagnostics, and has become standard in all vehicles to monitor the engine and emissions of the vehicle. In case of a minor issue, the light will turn on and stay lit – this is usually a loose gas cap, or a failing oxygen sensor. In case of a major issue like a catalytic converter failure or other more serious problems, the light will flash on and off.
Some have argued that the system was put in place for dealerships and mechanics to get more money in maintenance costs from their customers , but there is no need to go straight to the mechanic if the CEL comes on (an exception to this is if the CEL is blinking – then you need to stop the car and have it towed to a mechanic right away.) If something goes wrong with your vehicles monitoring systems, it will trigger a code that is specific to the problem your engine is experiencing. You can purchase a code reader to get these codes from your vehicle via a small plug on the underside of your dash.
Nowadays OBD-II code readers can be purchased just about anywhere for you to diagnose why the CEL came on. They usually cost what a mechanic would charge you for checking it once – and of course you get to keep it forever, so it pays off after two uses. Some readers will just tell you the code itself, and others will tell you what the code actually means in English. If your reader just gives you a code, say P1443, you can go on the internet and type in your year, make, model, and your code and it should come up with a definition of what the code might mean. Of course, if you are unsure, it’s always best to take it to a licensed mechanic.
Once you know what is wrong with your vehicle, you can go about fixing it. Simple repairs like a mass air flow sensor gone bad can be done at home in the garage, while more intricate repairs need to be done by a licensed mechanic. Either way, knowing the issue is the most important step for fixing the problem. Next time your CEL comes on, you will at least know what it might mean and take the steps necessary to remedy the problem.