If you’re a BMW i3 owner, you may have noticed an unusual message appearing on your dashboard. It typically goes something like this:
“Drivetrain Malfunction: Drive moderately. Maximum drivetrain output not available. Consult service center.”
If you’ve seen this message or a variant of it, then you’re actually in a club of many BMW i3 and other BMW owners who have experienced the same. What is this error? Why does it occur? What should be done about it? These core questions and more form the focus of today’s blog.
What is the “Drivetrain Malfunction” Error? Why Does it Emerge?
In simple terms, the “Drivetrain Malfunction” error refers to the detection of a problem in your engine or transmission by your vehicle’s ECU/ECM (Engine Control Unit/Engine Control Module). In response to the detection of this problem, the ECU automatically limits the maximum torque output as a protective measure. The goal is to prevent any further damage while you get the car to a BMW service center.
The issue is usually dealt with by connecting an OBD-II scanning tool and getting the error codes to guide a professional technician to what needs repairing. At an official or recognized BMW service center, they’re likely to use a BMW scanner, which will deliver the faults specific to the BMW vehicle both from the Digital Motor Electronics (DME) module and the transmission module. The BMW scanner is best because it can recognize all of the manufacturer-specific codes.
As for why it emerges, there are many possible reasons that can trigger the error. Unfortunately, it’s a fairly wide spectrum that makes it hard to pin it automatically down to one particular problem. In the next section, however, we’ll deal with the signs that your BMW i3 is experiencing this issue.
Are There Any Signs of the “Drivetrain Malfunction” Error?
Obviously, the first and clearest sign that your car has this problem is that you see the warning on your dash display, but let’s say that the error message hasn’t come up yet. What other signs are there that your i3 might be experiencing this problem, or that the error message could be imminent?
- Shaking or Vibrations – Have you noticed your i3 starting to shake or shudder? It might not be as pronounced on the i3 BEV as it might be on BMW models that carry internal combustion engines. If your i3 has the range extender unit, however, then you might feel it more. Unexpected juddering or shaking could easily be a precursor to the error message, and often is.
- “Check Engine” or “EV System Warning” – if you drive the i3 REx model then your car does have a small power-generating engine and exhaust, and there is a “Check Engine” light just as you’d find on a regular gasoline car. This means you can still get that warning in your i3, and it is often a precursor to the drivetrain malfunction. If you have the pure BEV, it might come in a different form, but it will still give you a system warning.
- Vehicle cutting off after idling – if you’re idling in your i3 and then put it into drive, but the system cuts out, this could also be a sign of the drivetrain malfunction.
- Smoke from the exhaust – this one only applies to the i3 REx since the regular BEV model doesn’t feature an exhaust, of course. Any excess fumes from the REx unit could signal trouble ahead.
- Loss of power – Finally, the tell-tale sign that unites pretty much all cases of the drivetrain malfunction is a loss of power. Remember that the malfunction causes a reduction in maximum torque output, so that brings with it a loss of overall power.
What Steps Should You Take to Fix it?
There are a few steps you can take to examine issues, and one or two things you might try that don’t necessarily require the expert hand of a mechanic or BMW technician. Should any of the following steps prove fruitless in removing the error message, then your best course of action must be to take the car to a BMW service center and have it checked there.
Regardless of your personal skill or confidence when it comes to automotive repairs, that course of action must always remain in your mind when you reach a point where safe experiments and trial and error yield no positive results. To push your inquiry too far could risk further damage to the vehicle. For our examples below, we will use a BMW i3 REx model as our example for the steps below since it contains all the possible parts to experience the error.
Step 1: Pull Over and Restart
The first thing you can do is to take a “wireless Internet” approach to the whole problem by finding a safe place to pull over, switching the car off fully, waiting 5 minutes and then restarting. This might not solve the malfunction, but it could reset it and allow you to drive normally and without restriction as you try to get the car to a service center.
Step 2: Inspect the Engine
Of course, for many BMW models, checking the engine is as simple as lifting the hood, but in the case of the i3 REx, you have to access the engine from the trunk, lifting up first the floor mat, and then unscrewing the metal engine bay covering. If you want to do things like top up the oil or other fluids, this is where you add them from. Check the oil level and ensure that the engine isn’t running too hot. Either of these things — among others — can cause the drivetrain (or any of the drivetrain components) to malfunction.
Step 3: Scan with a BMW Scanner
As we mentioned further above, a BMW scanner is a great tool to get the exact manufacturer-specific codes. Four particularly good models include:
- The FOXWELL NT510 Elite
- The AUTOPHIX BMW Diagnostic Scanner
- The ANCEL BM700
- The Creator C310 Plus V11.7.
These will deliver codes from the DME and the transmission, which will give a much clearer idea on what is going wrong in the vehicle.
Step 4: Take the Car to a Service Center
If you get stuck on any of the above points and/or you lack any of the equipment we mention above, then the best place to locate someone with the know-how and the gear is to head directly to your BMW service center.
Cost of Repairs
Hopefully the problem is something trivial such as spark plugs, because replacing or repairing those will probably cost less than $100 or so. If it’s your powertrain control module that is on the fritz, then you’re looking at potential bills of $2,000 to replace it if you’re not covered by any warranty.
Since most of the error messages are caused by fairly minor problems, you shouldn’t expect skyrocketing auto shop bills when dealing with this problem. Many can be scanned by a technician and dealt with with minimum fuss and minimum labor.
Finally we come to the question of prevention. Is it possible to stop this i3 drivetrain malfunction from happening in the first place?
The problem of the drivetrain malfunction doesn’t just occur in BMW i3 models, but also in many other BMW models. It seems to be fairly ubiquitous across the range. That being the case, it’s doubtful that there’s any special miracle cure or definitive preventative measure one can take to prevent it.
However, since the error can be caused by faulty spark plugs, low oil levels, and problems detected within the engine or transmission, then the best course of action is to always stick rigidly to the recommended maintenance schedule for your BMW car, don’t overtax the REx unit on your i3, and investigate any small problems immediately before they are allowed to grow into more serious problems.
I’m Planning on Buying a Used BMW i3 – Should I Be Worried?
“Worried” might not be the best word, but perhaps “aware” is a good choice. You should be aware that this problem does exist within BMW cars, and you should take steps to find out if the i3 you are buying has experienced these problems in the past. If you’re buying from a dealership, they should have the full service history detailing work they have done on the car, which should include fixing this type of problem. If there’s no history indicated of that issue, then you should be safe.
This particular error can happen at any point in the BMW’s life. This is what’s particularly frustrating to some owners. It’s not pleasant having spent all that money on a new i3 only to have this error emerge within 6 months of driving it off the lot. Therefore, you shouldn’t judge newer cars as immune from the issue. Check the service history, and if you’re buying from a private seller with gaps in the service history, then have an independent inspection done on the car to determine if the vehicle has any signs of experiencing or potential to experience the same problem.
These are all practical steps you can take.