It was annoying to see your engine management light (EML) illuminate on your car’s dashboard, right? You probably had to park the car as quickly as you could in a panic, especially if you saw a red EML alert. An implosion, explosion, or critical damage could occur in the engine!
In this article, we will explain what the EML on BMW means and the various reasons it lights up in this guide. Also, you may not have to think of the situation as much of a hassle with the steps that have been illustrated here to possibly turn the light off the DIY way.
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The meaning of EML on BMW cars
You can call the engine management light (EML) on BMW the engine warning light or check engine light (CEL). It may come on when there’s a glitch, engine fault, or emission problem. There can be more than one issue associated with the appearance of the light. You may or may not need to park the car depending on the circumstances.
The EML is connected to a Bimmer’s ECU (engine control unit). It’s triggered when the information gotten from the sensors of the exhaust system and engine contains abnormal data. A faulty sensor might also cause it to light up.
Some cars can show the EML in a variety of colors depending on the seriousness of the issue. It’s best to read the manual of your BMW to know the different ways the light can be displayed and what each signal means.
EMLs usually come on as amber or red when there’s a fault in the powertrain or an issue with emissions. You may be able to continue driving but ensure that the car is assessed ASAP.
A flashing amber light could mean an engine misfire. You can be sure of this if the car is shaking, vibrating, and/or sounding abnormal. You would have to stop driving and park the car to check what’s going on. Another option would be to drive slowly until you get to an auto repair shop. This is at the risk of overheating and damaging the exhaust system’s catalytic converter.
Lastly, a red EML shows that the issue needs urgent attention. Stop and park the car as soon as you can—when it’s safe to do so. Critical damage may be sustained if you keep driving for long.
Reasons that EML comes on
Loose petrol cap
The replacement of fuel pumped out of it with air ensures the balance in fuel tank pressure. A loose or broken fuel cap could allow the passage of more air than is necessary.
The sensor that supervises tank pressure would alert the ECU in the case of a problem which would, in turn, make the EML illuminate. The risk of damage is low and all you have to do is tighten the petrol cap or swap it for a new one.
Throttle position sensor
The EML on BMW can come on when a TPS (Throttle Position Sensor) becomes defective. Hopefully, it’s just the number 1 TPS (located above the air filter) that’s faulty. Because it’s the simplest one to replace. Carefully replace the TPS so that the screws don’t get stripped.
An oxygen sensor would notice that your BMW is operating on high or low-quality fuel. The sensor may develop a fault that can be fixed by recalibrating/reprogramming the ECU. It’s advisable to let a professional handle this task.
Oxygen sensors (typically two in recently introduced car models) do the opposite of what mass airflow sensors do. They assess the amount of air leaving the engine through the exhaust pipe. Mass airflow sensors, on the other hand, determine the amount of air entering into it. An EML icon would brighten up when an irregularity has been discovered by the sensors and reported to the ECU.
Diesel particulate filter (DPF)
Soot is produced when fuel and air are fired in a car’s engine. It is the particulate filter for the sake of reducing engine pollutants that collects the soot. DPFs are now being installed in petrol vehicles. The particulate filter may have its warning light depending on the vehicle model.
The warning light of the particulate filter may come on when it gets blocked by soot. You can simply boost the speed of the engine to increase its temperature and make the soot dissipate. However, the EML will signal you in the case of a worse situation. A defective differential pressure sensor can make the EML light up when the ECU can’t get data concerning the DFP.
Fix the issue on time to avoid spending money on a faulty filter which is costly to swap with a new one. The risk associated with DPF damage is high but you can continue driving towards a technician’s garage. Although this should be at a reduced pace.
Mass airflow sensor
The smooth working of your Bimmer’s engine is partially made possible by the mass airflow sensor. An imbalance in the flow of air and fuel will cause the engine to perform poorly. For example, rough idling and bad acceleration. It may also affect the exhaust system. As the result, the EML may light up because of these issues.
Mass airflow sensors provide ECUs with data that can be used to measure how much fuel is needed in combustion chambers. Thereby, the quantity of air (also determined by the mass airflow sensor) flowing into the engine can be matched.
A defective, blocked, or absent air filter can damage the mass airflow sensor of your car. This will lead to the illumination of the EML. The risk of damage is low, but you’d still have to decrease the speed of the car on your way to the auto repairer’s shop. Endeavor to change the air filter every two years.
Ignition systems ensure the correct firing of fuel and air in engines. The engine management light may brighten up when there’s a problem with the coils or spark plugs in an ignition system leading to an engine misfire. The risk of damage is medium in this case.
You’d need to slow down when driving to the nearest mechanic workshop for a vehicle assessment. It’s a situation that requires caution because it may affect the car’s performance in certain ways. Systems like the catalytic converter could also sustain damage.
Steps to clear EML
Resetting your EML is a simple process. You can decide to check the vehicle’s manual to understand the situation. An OBD2 scanner can be used to ascertain what the fault is and also clear the light. Take the following steps if you’re into DIY fixes:
Get a scanner
Purchase an OBD2 scan tool if you don’t already have one. It’s essential to diagnose the vehicle for defects or error codes (and clear them).
Locate the BMW’s OBD port
It’s easy to find the car’s OBD port. Just check the footwell on the driver’s side for it—below the steering wheel (above the accelerator pedal). You can search for the location of your Bimmer’s OBD2 port on Google.
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Plug the wireless adapter to the port
You first need to insert the wireless adapter of the scan tool into the port. Then, you can begin the activation process with the aid of a compatible software application installed on your smartphone, PC, or the built-in monitor that the product came with.
Prepare the car for a wireless connection
Ensure that the vehicle is ready for the scan by performing some necessary actions such as the following:
- Putting the ignition on
- Turning off or disconnecting third-party devices
- Activating the car’s diagnostic mode
Run the diagnosis
The scan can be done after you must have successfully connected the adapter to the software application via Wi-Fi, Bluetooth, or other means. You can clear the error codes once you finish getting and reading them.
The EML on BMW may reset itself depending on the model of your Bimmer and the kind of issue that triggered it to come on. You’ll require the help of an OBD2 scan tool to perform a manual reset on most occasions.
Please avoid purchasing knock-off scanners that may give you more problems instead of fixing them. Ensure that you know how to use the product well before starting the scan. Universal scanners or code readers may not give you all the codes shown in the diagnosis. It would be wise to purchase a scanner that’s specific to BMWs to get all the relevant codes.
You can clear the light by disconnecting the car’s battery cables if you’re sure that there’s nothing wrong with the engine. The next step would be to drain any leftover current by pressing down the car horn for some seconds.
Another method is to put the ignition on and off three times with just one second between each interval. You could even wait for some days for the light to go off. Determine what the fault is and fix it if the light keeps coming back on.
Make sure to check the Bimmer’s manual for instructions before proceeding to fix the problem. It might help you avoid doing more than is necessary for working on the vehicle. You would also be sure if the situation requires a higher level of expertise than yours as a DIY repairer. If that is the case, visit an authorized mechanic for a check. Keep in mind that the problem can be an electrical or mechanical one.