BMW IBS Sensor

BMW Intelligent Battery Sensor (IBS)

In this article, you will learn about the BMW intelligent battery sensor or also known as BMW IBS. BMW intelligent battery sensor is connected to the negative terminal of the battery. 

We will discuss what IBS sensor does, common problems with BMW IBS sensor and how to troubleshoot IBS problems yourself.


What is BMW Intelligent Battery Sensor

bmw intelligent battery sensor

BMW cars depend greatly on the battery not just for starting the engine but also for many other functions. 

Battery plays a critical role in BMW cars. Intelligent Battery Sensor (IBS) is used to monitor various battery parameters such as voltage, current, and temperature. 


The IBS sensor is mounted on top of battery negative terminal and has the ground cable and two connectors. One of the IBS cables connect gets power from the positive terminal. The second cable is connected to the DME and measures the battery load. This is known as the Bit Serial Data Interface or BSD. 

Purpose of BMW IBS

BMW IBS sensor measures several battery parameters such as:

  • Terminal Voltage
  • Charging current
  • Discharge current
  • Battery Temperature
  • SoC (State of Charge)
  • SoH (State of Health

Symptoms of a bad IBS sensor

  • BMW battery will drain when parked
  • BMW will not go to "sleep", drains the battery
  • Dead car battery
  • IBS not able to wake up the DME
  • Voltage fault, DME not on. This can be caused due to a short to B+ line. 
  • Voltage fault DME on, which can be caused to ground short

BMW IBS Sensor Recall

From time to time BMW may recall vehicles if they have been manufactured with safety defects. To find out if there is a IBS sensor recall on your BMW you need to call the dealer and provide them with the VIN number or check for recalls online. 

Check BMW IBS Sensor Recall


BMW IBS Sensor Bypass


Disconnecting the IBS cable from the negative terminal will disable the IBS communication with DME. This is not a solution. Bypassing BMW IBS sensor is not recommended. 

If you bypass the IBS sensor no information from the battery and its charge status will be available for the DME. 


BMW IBS Sensor Price

A brand new BMW IBS sensor costs anywhere from $150 to $250 depending on the series. 


How to troubleshoot IBS sensor

diagnose bmw ibs sensor with an obd2 scanner

Fault codes related to the IBS sensor are stored in the DME module. The DME will perform a check of the current, voltage, temperature.

To find out if the IBS sensor on BMW is defective we scan the DME module for fault codes. You will need a BMW specific scanner for this task. Follow this guide on how to scan BMW codes. 

Common IBS faults

  • Voltage Fault DME
  • 299B DME Intelligent Battery Sensor
  • 002E8D DME: Intelligent Battery Sensor, signal transmission

Additional Resources

  1. BMW TIS - Intelligent battery sensor_ E60, E61, E63, E64 Installation location Item Description.pdf 
  2. BMW IBS – Intelligent Battery Sensor – What Is It, What Does It Do?
  3. BMW Intelligent Battery Sensor (IBS)