BMW Passenger Restraint System Malfunction: Causes & Fixes

bmw passenger restraint system malfunction

On a normal day while driving your BMW, if you are getting a passenger Restraint System Malfunction alert, and you’re freaking out what is it? then don’t worry today we’re gonna explain this topic in detail.

The passenger restraint system is an essential system in BMW that ensures the safety of passengers during a crash or any accident. This system deploys the airbags and other protective measures during an accident of the vehicle.

And an error means your airbag and seatbelt are not functioning properly.

So, you should never ignore this warning, the Passenger Restraint system malfunction error needs your immediate attention.

What Does The Passenger Restraint System Malfunction On BMW Mean?

The passenger restraint system In your BMW is a very important function, that controls security measures like airbags, seatbelt tensioners, and different networks of sensors that deploy the security functions during an accident.

This is a security system that reduces the effect of the collision. Many senses measure different aspects of the vehicle like velocity, impact, etc. and when this sensor is alerted it deploys the airbag and seatbelt tensioner to secure the passenger.

If the passenger restrain system malfunctions and the SRS warning light also pops up, it indicates your safety system is not working properly.

This warning light indicates the airbag and seatbelt tightening won’t work in a crash.

So, now you know the BMW passenger restrain system’s meaning & importance. And it must be very concerning(it is), however when you’ll know all about this you can easily fix this error by yourself or by an expert.

Symptoms of BMW passenger restraint system malfunction?

There are many symptoms you can check to ensure the passenger restrain system is malfunctioning. If you identify any of these symptoms, quickly take the necessary steps to resolve this malfunction.

1. Warning Message

The most common way to know if you have passenger restraint malfunction is your BMW will pop up a passenger restraint system malfunction error on your dashboard. The written sentence will vary depending on your BMW model, but the error is the same.

However, the meaning of the error is your passenger restrain system is malfunctioning, which means the airbags, seat belt tensioner, or belt force limiter is not working properly. And, you should also wear your seatbelt and take your vehicle to the nearest service center.

This is the simple meaning of the warning error you’re getting.

2. Airbag Indicator Light On

A major sign of a malfunctioning restraint system is the airbag indicator light stays on. The airbag indicator light usually comes on when someone sits in the passenger seat.

The persistent airbag light indicates that the airbag is not working properly. This means the airbag won’t pop out during any collision and save the passenger. So, this light is an indication of huge concern.

3. Unusual Seatbelt Tensioner

The seatbelt tensioner is made to tighten the seatbelt with the passenger to their seat. But when a passenger restrain system is malfunctioning, it can cause the seatbelt tensioner not to work properly.

While driving aggressively, or on bumpy roads you’ll see the seatbelt tensioner working is very inconsistent, which is a big indication of the passenger restrain system malfunctioning.

Causes Behind the BMW Passenger Restraint System Malfunction

There can be many reasons which can cause the BMW passenger restraint system to malfunction. But the major reason can be the airbag system or wiring failure.

So, let’s look at the causes in detail to find out the actual culprit.

1. Water Leakage

The water from the engine could leak out and damage the passenger restraint system. As, you know leaked water could get anywhere in the vehicle, and do massive damage to different components, especially the metal components, and wirings.

So, if any part is found damaged from a water leakage replace the part as soon as possible.

2. Airbags not working

One of the simple and major reasons for the passenger restraint system is the airbag/airbag sensors are not working. The airbag sensors detect any impact and signal the airbag control module to deploy the airbags.

The BMW has an airbag on the steering and another in the dashboard for the passenger. In different models, there can be side airbags and curtain airbags. A wire harness connects your airbags to the vehicle’s internal operating system. However, any connection issue or damaged sensors can result in unresponsive airbags.

If this is the case then you should replace the damaged airbag sensor, which can be a bit expensive. On average replacing the airbag sensor would cost you around $550 to $670, including the airbag sensor and labor cost.

3. Wiring Issue

The passenger restraint system including the airbag control module is connected to the impact sensors with very critical wirings. Any damage in the wiring can prevent the airbags and other safety systems from working properly.

4. Low Battery Voltage

The whole passenger restraint system is run on electricity, but if the electricity is not enough then the system and senses won’t be able to gather enough data to function properly.

So, if the vehicle has a low battery voltage then it would not supply sufficient electricity, to the restraint system, and the passenger restrain system light will turn on. Also, the airbags may not work as effectively.

5. Control Module Failure

The control module can be another reason for the passenger restrain system, it is the brain of the passenger restrain system. The control module gets data from all the senses about any impact and ensures the deployment of airbags, activates seatbelt pre-tensioners, and other safety measures.

If the control module fails, then the whole safety feature goes down, and results in a passenger restraint system malfunctioning warning light on your dashboard.

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6. Issues With SRS

The SRS or Supplemental Restraint System has different senses that detect any collisions and send signals to deploy airbags and other safety measures.

When you drive too roughly, it is sufficient to alert the senses but not sufficient for deploying airbags, but it can cause a warning light.

Other times the impact sensors might be damaged, which will eventually result in passenger restrain system malfunction.

There are also many other factors that can cause this malfunction. Before fixing any problem you should find out the root cause first. Here are some other problems that can cause this issue:-

  • Occupancy Sensor Failure
  • Seat Belt Tensioner Defect
  • Belt force limiter
  • Defective clock spring
  • Software Glitches

How to Diagnose Your BMW Restraint System

Before fixing any problem you first have to know the root cause of the problem, only then you could fix the issue properly. So diagnosing your vehicle properly will help you understand the specific problem that is causing the issue, and then you can fix it yourself or get professional help.

Self Diagnosis

For this diagnosis, you’ll need a BMW OBD-II scanner, which you will easily find.

So, let’s look at the step-by-step diagnostic process:-

Step 1: Park your BMW with its parking brake on.

Step 2: Locate the diagnostic port, which is located under the dashboard.

Step 3: Now you should turn on the ignition, but don’t start the engine. And turn on your scanner and let it connect with your vehicle.

Step 4: Then you can select from the main menu, your vehicle “BMW”, then the model.

Step 5: Now the scanner should have communicated properly, select the control unit, and then go to SRS (Air Bag).

Step 6: Then select read fault codes, and here you can see the fault code, its description, and the DTC status.

Step 7: You can have more than one error, then every error will show up there with its error code, and DTC status (where “Current” means the problem persists).

Step 8: After knowing the issue you may have fixed the issue by yourself or by a professional technician. Then come back to the SRS(Airbag) section and there will be an option called “Clear the Fault Memory”, go to that and clear the fault code memory.

However, before doing a fault code diagnosis, you could also perform a visual inspection, some times minor wear and tear in the seat belt sensors could also cause this issue. Look for any damage in the airbag system, wiring or it’s sensors.

Professional Diagnosis

If you don’t have any required tools, or expertise, then you should take your vehicle to your nearby BMW service center or any trusted Auto shop for a detailed Diagnosis. They have advanced tools and expertise to inspect your vehicle for any error that is causing the Passenger restraint system malfunction.

How To Fix The Passenger Restraint System Malfunction BMW?

The passenger restraint system is one of the most important parts of your vehicle. As stated earlier the malfunction warning is a cause of big concern.

This is the safety system in your BMW, which saves the passenger during any accident. In the above, we showed you the step-by-step guide to diagnose your vehicle all by yourself and if you’ve done then you’ll get the specific error code. Now let’s see how can we fix those issues.

  • Inspect your vehicle for any internal water leakage, if any damage from the water leakage, replace/fix the component quickly. If you find any potential leakage then if not fixable, replace the component. (it’s better to just replace any leaking component)
  • If any damage is located in the airbag wiring, then replace the wiring. (or if repairable then repair that)
  • If the SRS system is doing the trouble you can opt for new SRS sensors.
  • If the battery has a low voltage, you could try to correct the battery connections and simply charge the battery with a dedicated battery charger.
  • If the passenger occupancy sensors are not working properly, you should replace them.
  • Look for any damaged passenger restraint system fuse, if found then replace them with a new one.

You may be able to find the problems, but can’t replace or fix any parts, then it’s fine just tell your service center or any certified autoshop mechanic about the problems and they will replace or fix it. They may also perform a diagnostic process to ensure that the issue is correct.

With their advanced tools and expertise, they will more efficiently find out the exact problem.

FAQ

How Much Do I Spend On Replacing The Airbag Sensors Of BMW?

The airbag sensors are pretty much expensive to replace. It would cost you anywhere around $550 to $670, including the airbag sensor and labor costs. I’m assuming you are not an expert and not gonna replace them by yourself. If you replace them yourself then you can bring the cost to around $200-$400.

BMW passenger restraint system meaning

The passenger restraint system in BMW is a very important safety function, which controls the airbags, seatbelt tensioners, and other safety measures in your vehicle.

Can I Drive My BMW With A Passenger Restraint System Malfunction?

YES and NO, yes technically you can drive with a passenger restrain system malfunction in your BMW, but it is never a good idea and never advisable to drive with a passenger restraint system malfunctioning vehicle. Because in case of any collision the safety features won’t work and could be very fatal for the passengers, and also the driver.

Is Replacing The BMW Passenger Occupancy Sensors Costly? 

In comparison to the crash sensors, the passenger occupancy sensors are quite cheap. On average, the sensor should cost you about $100-$120, and the labor charge may be $100-$150. In total, it could be done for about $200-$300.

How to turn off the passenger restrain system BMW?

Turning off the passenger restraint system is not advisable, because this is the safety feature of BMW. If you are facing any issues you could simply contact your BMW dealership service center or an expert technician.

BMW passenger restraint system malfunction reset

Resetting passenger restraint malfunction requires expertise, you should contact your nearby BMW service center or any trusted Auto shop. And I’ve discussed above about the diagnostic and steps for removing the warning.

Conclusion

Now you know what is passenger restraint system, its importance, and how important a passenger restraint system malfunctioning error is.

You’ve also read the common causes, symptoms, step by step diagnosis methods, and fixing methods. If you’ve got any problems along the way you can comment down below.

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