Check Engine

Reliable Vehicle Service & Care Info

The dashboard of a 2020 BMW 4 Series is shown.

A Driver’s Guide to the BMW Check Engine Light

Ah, the dreaded “Check Engine” light – few things are more worrisome/frustrating as a car owner than when this monster comes on. While this is true of any vehicle, when you are driving an expensive luxury car like a BMW, then seeing this light come on can be even more alarming. There’s a bit of a good news/bad news situation here. The good news is that your BMW check engine lights and other indicators are not always the end of the world, and you might be able to fix the issue yourself.

The bad news, however, is that these lights can indicate that something is seriously wrong and that your vehicle needs professional help. But knowing which indicator you are dealing with, what it means, and how to deal with it can be a bit tricky. After all, the last thing you want to do is gamble with the wellbeing of your beloved Bimmer and find yourself with a serious repair bill.

Let’s take a look at some of the different warning lights you might see, including your BMW check engine light, what they can mean, and what you should do if you see them come on. Some of this will be pretty straightforward, but some of it can be a little trying. Just remember: Don’t Panic! We’ll get through this together, and you can get back to enjoying your Ultimate Driving Experience.

Several BMW check engine lights and other warning lights are shown in the speedometer area.

Twinkle, Twinkle, Warning Lights

Alright, first things first: let’s take a look at a bunch of the possible warning lights you might see on your BMW, including the Check Engine light itself. Keep in mind that depending on what model and year you have, some of these might look different or be in different places on your instrument cluster. So rather than tell you what it will definitely look like, I’m going off what it will probably look like – but you can check your owner’s manual to be sure.

Some of the most common warning lights you will see include:

The red airbag warning light is shown.

Airbag System

This typically looks like a person sitting sideways and blowing a huge bubble out of chewing gum, but I’m pretty sure it’s meant to represent an airbag. When you see this light, it means something has gone wrong with your airbag system. Hopefully you see it before a Collision – get this checked out right away just to be safe.

The red ABS warning light is shown.

Antilock Brake System

This is pretty straightforward and usually says “ABS” with a ring around it. The light means something has gone wrong with your antilock brakes. Get it checked out immediately and in the meantime, drive slower and brake more gently.

The red airbag warning light is shown.

Battery Indicator

If you see this light, it usually means your battery is on the way out, though there could simply be a faulty connection. It typically looks like a rectangle with a + and – sign, though it can also say “battery.”

The red Brake warning light is shown.

Brake System

This is a general warning about your brakes, not specific to your BMW’s antilock brake system. Just like the ABS light, get your brakes checked right away and drive very carefully in the meantime.

The red low brake fluid light is shown.

Brake Fluid Level

You usually see this indicator as a “!” that can light up in yellow or red. A yellow warning means your brake fluid is low, and you need to get it refilled, so drive carefully. If the “!” is in red, it means your hill brakes have failed, so you will roll on an incline once you release the foot brake.

The green bulb warning light is shown.

Bulb Warning

This means one of your exterior bulbs has gone out and usually looks like a little light bulb. Get it replaced right away, and until you do avoid driving at night – it’s unsafe and a good way to get a ticket.

The check engine warning light is shown.

Check Engine

This is the very BMW check engine light we were talking about earlier, and it’s a big one. You might see it steady or flashing, and it means different things. This one is too important for a brief description, however, so we’ll look at it more below.

The coolant level warning light is shown.

Coolant Level

The name is pretty straightforward here; it means your coolant fluid is low, and you need to add more. This indicator typically looks like a rectangle with little waves at the bottom of it. If you refill your coolant and the light comes on again soon, it could mean you have a leak or other issue.

The red door ajar warning light is shown.

Door Ajar

Close your door! This indicator looks like an overhead view of your vehicle with a door open, often showing which door is open. If all of your doors are secure, but the light is still on, then you could have an issue with a sensor.

The yellow low fuel warning light is shown.

Empty Warning

This is your typical low gas warning and looks like a gas pump. You need to refill your gas tank as soon as possible – don’t trust that you have plenty of time.

The red engine temperature warning light is shown.

Engine Temperature

When you see this warning light, it means your engine is overheating. Get to the side of the road safely, come to a stop, and turn off your vehicle. You might need coolant, or it could be a bigger issue.

The yellow gas cap warning light is shown.

Gas Cap Warning

This light means your gas cap is either missing or loose. Tighten your gas cap to make sure it’s secure, and if the light stays on then you might need to replace the cap. It may appear as a check engine light on some vehicles.

The red oil level warning light is shown.

Oil Level Low

Just like it sounds, you are low on oil. You can add some yourself or take your vehicle in for an oil change if it is due. If you frequently need to add oil, then you might have a leak or other issue.

The orange service warning light is shown.

Service Vehicle

This is a general indicator light that usually means you are due for scheduled maintenance or service on your vehicle. It usually does not mean there is a critical issue, but it is just a reminder.

The red steering warning light is shown.

Steering System

If you see a symbol that looks like a steering wheel, then it usually means you need to adjust your wheel. Turn on your engine and turn your wheel all the way to the left and right several times. This should turn it off – otherwise, you need to have your steering system checked.

The yellow tire pressure warning light is shown.

Tire Pressure Monitor

Most BMWs have a tire pressure monitor that will warn you when your pressure is low. Check your tire pressure and refill them as needed to a safe level. If this light comes on frequently, then you may have a leak.

The yellow traction control light is shown.

Traction Control

This is a warning that your vehicle has poor traction – you’ll usually see this in rain or snowy conditions. Slow down, drive carefully, and be ready to have poor control over your vehicle.

The red warning light is shown.

Warning

This is a general warning light that usually looks like a “!” in a triangle. You will probably see other lights come on with it, but it can mean you are very low on gas.

The green low washer fluid light is shown.

Window Wash Fluid

You are low on window wash fluid, so refill it as soon as possible. Definitely not critical like some other lights, but still important.

That’s a lot of possible lights that can come on, but as you can see, some of them are definitely more serious than others. All of them are important, and when you see one come on, then it’s time to do something about it. Even something like wiper fluid can be vital if you find yourself in a dust storm or in snow and sleet. So it’s a good idea to take action right away when you see any of these lights come on.

It’s also worth noting that you will usually see them illuminate in yellow to let you know that you need to check something out, and you should be cautious. However, if you see a red indicator or warning light, that is usually a much more serious issue. You need to have your vehicle checked right away (or do it yourself if you have the right equipment). In some cases, a red warning light can mean you need to safely pull over as soon as you can and shut your car down before serious damage occurs.

Your BMW Check Engine Light

So, what about your specific BMW check engine light? Like I said, that one is so important it deserves a little more detail. So your check engine light will typically look like either a little engine shape, or it will actually say “Check Engine” in not-so-subtle English. Either way, it means the same thing: there’s a problem specifically with your BMW’s engine, and you need to address it as quickly as possible.

The frustrating thing is that a lot of different issues can cause your BMW check engine light to come on, including a faulty fuel injector, worn-out spark plug, and even a loose gas cap. You see, the gas cap needs to seal tightly to keep the pressure of your whole system where it should be, so a loose cap can actually create some very real problems. On top of all these potential causes, there are also two ways your BMW check engine light can come on: steady or blinking.

A steady light means there is an issue with your engine that you need to get checked out, but it’s not particularly catastrophic at the moment. You should schedule an appointment at your dealership or preferred garage and get it looked at as soon as you can, but you can keep driving it (maybe just don’t go on any long road trips). A blinking light is actually more serious and usually means there is a major issue with your engine.

Simple Possible Fixes

Like I said, one of the things that can trigger a BMW check engine light is a loose gas cap, which is allowing fuel to evaporate. One of the simplest things you can do is remove and re-secure your gas cap, making sure you tighten it properly and get it on correctly. This can actually solve the problem sometimes and fix the issue with your engine. It’s worth noting it can take a little time for the check engine light to go off if this was the issue, so you might need to run it and take it on a few short trips over a couple of days.

Faulty spark plugs can also be the cause of an illuminated BMW check engine light, which is a very cheap replacement. If you’re comfortable with changing your own spark plugs, then give it a try and see if that makes the light go out. Some other issues, like a failing mass airflow sensor, can be quite inexpensive to have replaced, even at a dealership. Ultimately, anything you need done is going to be cheaper than having your engine rebuilt or replaced.

Diagnosing a Problem

A mechanic is using a tablet program to diagnose the BMW check engine light.

If you want to know what’s causing your BMW check engine light to come on, you can get yourself an OBD Scanner and actually diagnose issues with your vehicle yourself. This isn’t for everyone, but if you’re a hands-on sort of person, then you should strongly consider this. These scanners are not particularly expensive, and while a general OBD Scanner won’t be as efficient as the BMW-specific ones that your mechanic probably has, it will still work.

You can connect the scanner to a port that you’ll typically find under the dash on the driver’s side of your BMW. It might take some looking, but it’s there. Plug your scanner in and follow the instructions on how to use it to find out what’s wrong with your vehicle. From there, you can either make necessary repairs or part replacements if you are comfortable with it, or take your vehicle to your dealership or garage to have work done.

The Golden Rule

I have a simple, golden rule when it comes to something like an illuminated BMW check engine light: don’t wait, take care of it immediately. I know too many people that see a warning light come on and just ignore it until they “have time.” But you’ll never really “have time,” and your engine is not going to wait for you to overheat, throw a rod, or seize up. So don’t wait, do the things you need to do, and get your engine looked at.