The drivetrain is a set of various parts that get their power from the prime mover (such as the engine) and provide this mechanical power to the driven parts of the vehicle. Drivetrain malfunction errors are rare in vehicles.
In the pages of automotive engineering textbooks, the drivetrain is one of the most components of the vehicle that delivers the power to the vehicle wheels. The drivetrain of your vehicle usually consists of several components, including a driveshaft, wheels, transmission, axle, and joints. But the engine is not included in these drivetrain components.
The BMW drivetrain malfunction is usually caused by a malfunctioning transmission system or engine. The BMW drivetrain malfunction message on the dashboard of your car indicates your powertrain control module (PCM) detects a problem with the car’s engine or transmission system.
What is a Drivetrain?
The drivetrain of your car acts as the bridge between the engine and the wheels. When your car engine starts, the drivetrain takes power by it and delivers this power to the car wheels using the transmission.
The drivetrain of your vehicle contains wheels, axles, transmission, joints, and the driveshaft. This integrated system of the drivetrain works with the engine to successfully provide power to the wheels.
Function of the Drivetrain in a BMW
The main function of the drivetrain in a BMW is the same as in other vehicles: it takes power from the engine and sends it to the vehicle wheels. The BMW drivetrain system usually contains CV joints, differentials, axles, wheels, and the transmission. So, if there is a problem with any of these components, the performance of your BMW will be compromised.
What does Drivetrain Malfunction Indication on a BMW mean?
A Drivetrain Malfunction Indication on the BMW indicates that the powertrain control module (PCM) of your vehicle detects a problem with the engine or transmission system of the vehicle. The drivetrain malfunction message may also indicate a malfunction in the fuel or ignition system of the vehicle.
In this condition, the car automatically goes into limp mode. The limp mode lowers the torque production of the vehicle through the PCM. Due to this limitation, your BMW is prevented from future harm to the engine or the transmission system. But still, this condition lets the driver drive safely to his/her destination.
Types of Drivetrains
The drivetrains have the following types:
- Rear-wheel Drive (RWD): In the rear-wheel drive car, the rear wheels of the car supply the power. In RWD, the transmission of the vehicle has a differential at one end and a long driveshaft at the other end.
- Four-wheel Drive (4WD): Conventional four-wheel-drive vehicles contain two driveshafts. Along with the driveshaft of the rear wheel drive, another front driveshaft is attached to the front differential and the transfer case of the front wheels to the u-joints.
- Front-wheel Drive (FWD): In the case of front-wheel drive, the front wheels are used to transmit the power. FWD has all the drivetrain components in the front of the vehicle. But instead of universal joints, constant velocity joints are used in the FWD.
Symptoms of BMW Drivetrain Malfunction
Whenever you see the drivetrain malfunction warning light on your BMW dashboard, you must remain calm. This sign acts as a warning for the owner to know the damage and resolve it to avoid any further damage. The following are the most common symptoms of drivetrain malfunction:
- Check engine light is illuminating
- Knocking sound
- The iDrive screen shows the drivetrain error.
- Loud clunking sound
- Insufficient power while overtaking the other cars.
- Issues while turning
- Rough idling
- Cutting off the engine while idling or D mode
- Your transmission is stuck in gears
- Unable to start the engine
- Smoke from the exhaust pipe
- Engine stalling
- Shake while starting
- Intense vibration in the vehicle compartment
Causes of Drivetrain Malfunction in a BMW
The BMW drivetrain goes bad due to one or more of the below-given causes:
- Bad Spark Plug
- Low-Quality Fuel
- Faulty Fuel Pump
- Damaged Fuel Injectors
- Bad Catalytic Converter
- Bad Ignition Coils
1) Bad Spark Plug
The damaged or failed spark plug is one of the major causes of the BMW drivetrain malfunction.
You may face misfiring issues due to failed or damaged spark plugs. These misfires occur due to the low or insufficient spark caused by faulty spark plugs. This difficulty while starting the engine may lead to the drivetrain malfunction indication.
Read More: Bad Spark Plug Symptoms and Causes
2) Low-Quality Fuel
Contaminated or low-quality fuel is a major cause of drivetrain malfunction. You should always check your fuel after a specific time interval. If it is contaminated, you should change it as soon as possible.
It is always recommended to use 93-octane fuel to avoid drivetrain malfunctions in expensive cars like BMW.
3) Faulty Fuel Pump
If your car shows a drivetrain malfunction error during acceleration, a high-pressure fuel pump may be damaged.
Fuel in the car is transferred from the tank to the engine through the fuel pump. This transfer is done by the pressure caused by compressing the fuel in the fuel lines.
A damaged fuel pump doesn’t properly supply fuel to the combustion chamber, resulting in low performance and reduced power. With this insufficient power production, the drivetrain malfunction error will cause the drivetrain malfunction light to appear on the dashboard of your car.
Read More: Bad Fuel Pump Symptoms and Causes
4) Damaged Fuel Injectors
The main function of the fuel injectors is to inject fuel into the combustion chambers. The faulty fuel injectors can’t efficiently inject the fuel into the combustion chamber, resulting in bad combustion and poor engine power.
A faulty fuel injector may also cause misfiring, engine stalling, vibration, and rough idling in your BMW. All of these are causes of the BMW drivetrain malfunction.
A failed turbo, a damaged head gasket, a bad MAF sensor, or low fuel quality can also cause some disastrous situations that lead to drivetrain malfunctions.
Read More: Fuel Injection System Working and Types
5) Bad Catalytic Converter
The catalytic converter is used to convert the highly toxic gases emitted from the internal combustion engine into less-toxic pollutants by catalyzing a redox reaction.
The catalytic converter converts highly toxic gases (like nitrous oxide and carbon monoxide) into carbon dioxide and water vapor.
In the case of a faulty catalytic converter, little gas will be emitted from the exhaust, making the internal pressure higher than usual. This increase in pressure causes the drivetrain malfunction error in your BMW.
Read More: Bad Catalytic Converter Symptoms and Causes
6) Bad Ignition Coils
The spark plugs of your BMW get power from the ignition coils. So, if the coils are damaged, the power will not be delivered to the plugs, and not enough spark will be produced. If your spark plugs don’t produce a sufficient spark, your engine cylinder may start misfiring, and you will see a clear reduction in the engine power.
How to fix a Drivetrain Malfunction
Here are the steps that must be followed in order to fix a drivetrain malfunction on your BMW:
- Restart your engine
- Inspect the engine
- Read trouble codes with a BMW scanner
- Replace spark plug
- Add quality fuel
- Replace fuel injectors
1) Restart Your Engine
In the BMW, if you restart the engine, there are chances that the drivetrain malfunction error can be removed. But if you get the drivetrain malfunction warning light appears during the drive, then follow these steps:
- Turn the engine off
- Remove the key from the ignition switch
- Wait for about 10 to 15 minutes, then start your engine again. There are chances that the malfunction warning will disappear.
2) Inspect the Engine
Always check your engine when you see the drivetrain malfunction error on the dashboard of your BMW. Raise the hood and check if there is any leak or any kind of smell that could be due to an oil or coolant leak or a damaged drive belt.
- Don’t excessively run the engine in case of overheating or low engine oil.
- Inspect the engine oil level. It must be according to the requirements.
- Check the engine temperature.
Read More: Low Engine Oil Symptoms and Causes
3) Read Trouble Codes with a BMW Scanner
Read the diagnostic trouble code using the OBD II scanner and check the cause. Once you read the codes, consult the owner’s manual, and fix it. Always use the one compatible with your BMW.
4) Replace Spark Plug
As we discussed above, the faulty spark plug is a common reason for the drivetrain malfunction. Therefore, properly inspect all the spark plugs for signs of damage. If any of your vehicle spark plugs are damaged, replace them immediately to prevent expensive damage.
5) Add Quality Fuel
Low-quality fuel usually reduces the engine’s power. But using high-octane fuel can restore engine power and eliminate drive train malfunctions in your BMW.
6) Replace Fuel Injectors
Inspect the fuel injectors of your vehicle. If they are damaged, then replace them immediately.
What is the cost to repair a drivetrain malfunction in my BMW?
The fixing or repairing cost of the malfunctioning drivetrain depends on the component that has to be replaced. Usually, the drivetrain malfunction message fixing cost is approximately $2600. If the spark plug has to be replaced, it will cost you about $90, and the repair of the catalytic converter will be costly, about $2400.
What is the function of the drivetrain?
The main function of the drivetrain is to connect the engine and vehicle wheels. It gets power from the engine and transfers this power to the wheels through transmission.
What does it mean on a BMW when it says "drivetrain malfunction"?
The drivetrain malfunction message on your BMW dashboard indicates that the PCM of your car has detected transmission or engine issues. This warning also means that there can be an issue with the ignition or the fuel system of your BMW.
Can I drive with a drivetrain malfunction on my BMW?
You can drive with the drivetrain malfunction, but it is not recommended. As the drivetrain issue keeps the power of the engine low. A faulty drivetrain also produces different drivability issues, such as engine stalling, misfiring, or hard engine starting. It may trigger your car in limp mode. So, when your car goes into limp mode, go immediately to the nearest service provider.
Is a drivetrain malfunction serious?
With drivetrain malfunction, low energy will be delivered to the wheels, and hence there will be problems moving your vehicle. So, it’s a serious issue. Therefore, it is recommended to fix the issue as soon as possible.
What are the parts of the drivetrain?
The following are the parts of the drivetrain:
- Transmission: It delivers power from the engine to the wheels.
- Axle Shaft: This delivers power to the rear drive wheels from the differential.
- CV joints: A CV joint can bend in any direction and allow the axle to change the direction of the wheels.
- U Joints: A universal joint is present at every end of the driveshaft. It enables the shafts to turn and move on bumpy roads.
- Driveshaft: A driveshaft is a steel cylinder that joins the transmitter to the axle of the wheel with the help of U joints. This driveshaft provides torque to the wheels. The drive shaft helps the transmission transmit torque to the wheels.
- Differential: It is present in the center of the axle and divides the power equally between each wheel.
What repairs can fix the bad drivetrain?
- Restarting the engine
- Replacing the faulty engine
- Replacing the bad spark plug
- Changing the contaminated fuel
- Replacing bad fuel injectors