Check Engine Light: What Does It Mean?
Your check engine light comes on, but what does it mean? What is it telling you and what should you do next? Many people panic, yet there is often no need to. However, it could also be trying to tell that you something serious is wrong.
Unlike the red oil can warning light, which means you must stop right now and check your oil level, it is not necessary to deal with the check engine light immediately. However, what it means is that you will have to visit your dealer or a Nissan mechanic to have the problem checked out.
The light will not just go off next time you start the car. It will remain lit until you have had the engine checked. That’s what he light is asking you to do, and is what you will have to do before it is switched off. The correct name for this light is the Malfunction Indicator Lamp, and the malfunction must be identified and rectified for the light to be extinguished.
Check Engine Light is On: Take Some Action
If the check engine light comes on you must take some action. In most cars, this will be an orange, amber or yellow light that might say “Check Engine.” You can’t just ignore it. In a few cases it might just go off again if the problem was transitory – caused by a change in humidity for example. However, such incidences are very rare.
The first action to take is to check all the obvious potential causes. Make sure everything is screwed down tight: the gas tank cap, the oil cap and all the various wires and plug connections. Make sure no wires have been damaged or have come loose, and that all your belts are tight. If the light is still on after doing all that, you will have to take your car to a dealer.
Engine Light Code Readers
If your car is later than 1996, there will be a universal connector that connects to a code reader. This will identify the fault causing the check engine light to illuminate. The connector is normally located beneath the steering column.
Your dealer will plug a decoder into this connector and decipher the code. This can be costly: some will charge up to $75 for this service – and that doesn’t include correcting the fault! Alternatively, you can purchase an on-board diagnostic (OBD) code reader to plug into the connector. These are available online or from most auto parts stores. Some stores might even read the code for you free of charge.
There are also iPhone apps available that you can use to diagnose the code, though you will need a cable to plug into the connector and then to the iPhone. Once you have the code, you can cross-reference that with the actual fault. There are cross-reference booklets available, or you can also find the codes online.
Some readers will switch the light off for you, although it will just come on again when you start the car if the fault has not been rectified. You can also disconnect the positive (red) terminal from the battery and leave it for 30 minutes before reconnecting. The light should be off when you start the car again. However, it will also likely come on again if there is still a problem.
Beware of What the Code is Saying
Beware of reading the problem too literally. If the code notes a fault in one of the components of your engine, it may not be that component at fault! All it means is the component is not working correctly. Taking it out and replacing it might not solve the problem and will waste your money.
That’s because the component may only seem to be faulty to the coder. It could seem faulty because there is a damaged or loose connection to it. The most common faults are the loose gas cap mentioned above, loose spark plug wires, problems with the catalytic convertor and problems with the oxygen and mass air flow sensors connected with the fuel mixture. These can be caused by faulty parts or fault connections to the parts and sensors. At least you will have a rough idea of where the problem might lie.
Never ignore the check engine light. In fact, no warning lights on your dash should be ignored. It is estimated that around 1 in 10 vehicles are running with a check engine light taped over. Such vehicles will not pass their state vehicle inspection, and you might eventually have to pay a lot of money to rectify a fault that could easily have been repaired had it been dealt with immediately.
If your check engine light comes on, either take your car to a dealer or decipher the code using one of the above suggestions. Then check the problem, and if needs the attention of a mechanic get the work done. The light will remain on until you do, and no car passes the state inspection with a check engine light illuminated.