BMW SOS Call System Failure – All You Need to Know

BMW SOS Call System Failure – All You Need to Know

The BMW SOS Call system is a safety feature allowing drivers to easily call emergency assistance during emergencies.

BMW SOS Call System Failure All You Need to Know

This system is created to be highly reliable and a critical component of BMW. It provides drivers with the highest level of safety and security.

However, like any complex mechanical or electronic system, the BMW SOS Call system can experience failure.

Understanding the causes, symptoms, and remedies of this type of failure for any BMW is important. We will provide an overview of the BMW SOS Call system.

Explore some of the most common failures and provide tips for troubleshooting and how to reset the system.

Causes of BMW SOS Call System Failures, Symptoms and Solutions

The common causes of BMW SOS call failures are a dead battery and bad wiring. Or a broken telephone box that may cause the SOS light to illuminate.

These causes are codable by BMW mechanics to prevent SOS message functions from appearing on your dashboard.

However, there are several potential causes of BMW SOS Call system failure.

Some of the primary reasons include the following:

Satellite Radio at Fault

You can use a BMW scanner to help you diagnose faulty satellite radio.

The BMW satellite radio might be located on the side or under the floor cover of your trunk.

Although, the placement of satellite radio may vary depending on your BMW model.

Defective satellite radio is one of the causes why SOS emergency call malfunctions; a mechanic can repair it.

However, buying a working used model or a new one may be more convenient than fixing the old one.

If you don’t want to use satellite radio, you can install a fiber optic bypass loop as an alternative fix.

Symptoms of broken satellite radio:

  • You will hear cracking sounds from the speakers.
  • The Bluetooth phone is malfunctioning.
  • The radio might work, but no sound.
  • The iDrive of your BMW will keep returning to the home screen.
  • SOS malfunction error appears.


When your satellite radio is at fault, disconnect the battery of your BMW for at least 12 hours. Or leave it disconnected for the whole night.

It will reset the malfunctioning of the MOST (Media Oriented System Transport) component or force them to reboot.

Defective IDrive Head Units

The iDrive of your BMW takes control of most of the secondary vehicle system in your car.

Some of the head units, such as CIC, NBT, and CCC, may develop problems that result in communication issues on the fiber optic loop.

Or it may completely shut down one of the head units.

Once head units have problems BMW SOS light will activate. You can also check the fuses of the backside of the unit if it happens.

Symptoms of defective iDrive:

  • You will hear noise from the speakers.
  • You will see damaged applications.
  • It crashes while downloading.


If the iDrive screen becomes blank, push the DVD eject, CD eject, or CD volume buttons simultaneously to re-initialize the iDrive.

BMW SOS Call System Failure All You Need to Know


After re-initializing iDrive, remove the Bluetooth phone from the iDrive settings menu.

Turning off the computer is not necessary, but it can help. Before you use the iDrive again, reconfigure it.

Ensure to restart the phone before you reconfigure the iDrive.

Or, for minor iDrive system malfunctions, you can reboot it to fix the problem. Here’s how you do it:

Turn off your car’s engine, leave vehicle accessories on, and push and hold the volume button for 30 seconds until the screen powers down.

Ensure to hold the screen for 30 seconds until the screen is off.

After 30 seconds, release the volume button and push it again to reboot the system.


The TCU or Telematics Control Unit is responsible for wireless tracking, communication, and diagnostics embedded in the inboard system.

It controls the following:

Bluetooth, BMW Online, Remote functions (remote door locking, heating/AC control, etc.) BMW Assist and Teleservices.

The TCU system is used for Emergency Call crash notifications.

It helps vehicle connectivity by using more modems for communication from the car’s cloud and vice versa.

If TCU goes terribly, you can’t reach the BMW assistance center, and it will trigger emergency call malfunction warnings.

Symptoms for bad TCU:

  • It will show malfunctions on the unit it controls.


When your TCU goes bad, take your car immediately to the nearest skilled mechanic to replace it.

That’s the only remedy since it involves wiring, to ensure your safety, it is recommended to leave the job to the experienced mechanic.

Fiber Optic Cable Has Been Damaged

If your BMW SOS call pops an error, it might be due to the damaged fiber optic cable.

You might accidentally disconnect it while you are working on your car.

Although fiber optic cable rarely has problems, it will be your last resort in diagnosing your BMW SOS failures.


To fix the damaged fiber optic needs to be spliced, and you need a mechanical splice kit.

Here’s how you do it:

  • Cut the damaged parts of the fiber optic cables.
  • Clear out the jacket of both cables until you see fiber strands.
  • Place both cable ends into the splice and push the lock button to lock them.

Defective Amplifier

BMW SOS Call System Failure All You Need to Know

If the amplifier is defective, it can cause problems with the fiber optic loop system.

It can shut down a fiber-optic loop and shut down when a faulty amplifier or Bluetooth is defective, just like iDrive’s unit heads.

You can check the fiber-optic bypass loop and the Bluetooth module under the floor cover of your BMW. Also, ensure to check fuses near the units for any signs of damage.

Symptoms of a defective amplifier:

  • The amplifier starts randomly.
  • There is an excessive distortion.
  • It reduces sound quality.
  • There is no output from the amplifier.
  • You can smell burning from the amplifier or overheating.
  • You can hear a slapping/popping noise from the subwoofer.


If your amplifier gets damaged, you better bring your vehicle to the nearest BMW repair shop to replace it.

The amplifiers are audio tools with complicated wirings and components only experienced mechanics can do.

How to Reset BMW SOS Emergency Call System?

Here’s how you can reset the BMW SOS emergency call system:

  • Press and hold the SOS button for at least five seconds to activate the system.
  • Deactivate the call; once you activate the call, a message will pop up to confirm if you want to make a call. Press the SOS button again to deactivate the call.
  • Check the system status; after deactivating the call, the system will return to its normal status. Press the SOS button again to check the status. Repeat the process if the system is still active.
  • Restart the car to check if the system works properly.

If the problem continues, you may need to take your car to BMW dealers or a professional mechanic for further diagnosis.

It is important to note that resetting your SOS system will not guarantee it will fix the problem.


The BMW SOS Call system is an important safety feature for drivers’ safety to call for assistance during an accident or any emergency.

However, the SOS Call system can sometimes malfunction or fail like any complex mechanical or electronic system.

Knowing the SOS functions and causes of malfunctions can guide you on what to do and how to troubleshoot it.

Overall, it is important to be aware of the SOS Call system and its functions and potential causes of failure to ensure the safety of the vehicle and its passengers.

Also, regular car maintenance can ensure all the systems and parts are working properly.