If you just encountered the dreaded “Ignition fault” message on your BMW, you’re not alone. It’s one of the most common problems reported in BMWs, and there are a few possible causes and fixes.
In this article, I am going explain what this message means, the leading causes, and how to go about fixing it. read on.
What Does Ignition Fault Mean on a BMW?
If your BMW engine is failing to start and ‘ignition fault” comes on your dashboard, it means that there is an issue with your car’s ignition system.
From my experience as a Mechanic, I can tell you that this fault is not only caused by the ignition system itself but it can also be caused by other components that are connected to it which I will cover below.
BMW “Ignition Fault” Main Causes
Now, let’s look at the main causes of ignition fault in a BMW.
1. Bad Battery Safety Terminal
A damaged battery safety terminal is the most common cause of the “ignition fault” warning in a BMW.
The safety terminal is a fuse that protects your vehicle from electrical fires.
When there’s an issue with this fuse, it can cause the car to shut off or fail to start at all as a result an “Ignition fault” warning to come on.
A battery safety terminal is located at the end of the positive terminal on your BMW.
2. Low Battery Voltage
A low battery voltage can also cause the “ignition fault” warning to come on.
If your car’s battery is low, it may not be able to power the starter motor or alternator properly.
This will prevent your vehicle from starting, as well as cause you to get an ignition fault message.
If you haven’t been driving your BMW for a while, it’s important to check the battery voltage before you try to start your car.
You can do this by using a multimeter and measuring the voltage between each battery terminal on your battery.
A battery that is dead can cause a low voltage problem as well, if your BMW battery is older than 4 years you should consider replacing it.
3. Faulty Alternator
The alternator is responsible for charging your battery and providing power to the electrical system in your BMW.
If it isn’t working properly, it can cause both a low voltage problem as well as an ignition fault message on your dashboard.
Although the alternator is not as common as a bad battery safety terminal or a damaged battery, it can still happen. If you have a faulty alternator, you should have it replaced as soon as possible.
4. Damaged Starter
The last common cause of ignition fault on a BMW is a bad starter.
The starter is responsible for engaging the engine in your BMW by turning over its flywheel when you turn the key.
If your starter isn’t working properly, then your engine won’t start.
How to Fix and Reset the “Ignition Fault” Warning on Your BMW
Now, that you know the possible causes of an “ignition fault” warning on your BMW, let’s talk about how to fix it.
Step 1
The First thing I recommend that you do is replace the battery safety terminal, these are relatively inexpensive and easy to install.
You can find the safety terminal by visiting the nearest BMW Dealership, searching “BMW battery safety terminal” on Google, or visiting any local auto parts store that deals with BMW and asking for one.
Once you get that part, replacing it is pretty straightforward and takes less than 5 minutes to do.
Then start your car and see if the issue is fixed. If it is not, then you will need to move on to step 2.
Step 2
If replacing the Battery safety terminal doesn’t fix the issue then, you might have a bad battery or alternator.
The next thing I recommend is to jump-start the car from a different vehicle and see if it starts.
If it does, then this tells you that the problem is with your battery or alternator.
If the car is still showing “ignition fault” and not turning on then the main cause is a damaged starter then taking it to BMW or an independent qualified mechanic is the best way to diagnose and repair it.
Additional Sources
https://www.bmwofmurrieta.com/parts/parts-tips/bmw-battery/
https://www.competitionbmw.com/how-to-tell-the-signs-of-a-broken-bmw-starter-motor/
Thank you very helpful
Hi, I get this problem when my car has been running for a while. If I stop for fuel after travelling a distance there’s a good chance it won’t start. When the engine is cold it starts no problem. Does this sound familiar?
Thanks,
Julie
Hi Jilie,
If I had to narrow it down to one likely culprit for your car’s issue of not starting when hot, I would point towards a problem with the fuel system, particularly the fuel pump.
When a fuel pump is failing, it often struggles more when the car is hot. The heat can exacerbate any existing wear or issues within the pump, leading to insufficient fuel pressure to start the engine. Once the car cools down, the pump might function well enough again to allow the engine to start.
Wery helpfull..regards from Serbia!