BMW CAN Network Problems

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Need to troubleshoot your BMW CAN Network Problems? Learn what CAN Network does, common problems, how to read/clear codes from CAN Network, and perform tests yourself.

What is BMW CAN Network?

CAN, or Controller Area Network integrates BMW control units into one network, which increases communication speeds while reducing the number of wires required for systems to communicate.

BMW CAN network makes it easy to perform diagnostics using a BMW scanner.

BMW CAN network connect various including transmission (EGS), Engine Control Module (DME), antilock brake (ABS), traction control/stability control system (DSC), electronic steering, climate control system, lighting control, and many more.

BMW vehicles may have more than one CAN network. Examples of BMW CAN Networks:

  • DT  Can (powertrain CAN)
  • F-Can (suspension CAN)
  • K-Can (body CAN)
  • MOST (Media Oriented System Transport)

Symptoms

List of possible symptoms you may notice if the CAN Network or one of its components fails.

  • No communication
  • No response from a single module
  • No communication via the OBD-II port

Common Problems

Possible problems that can trigger fault codes in the CAN Network.

  • Damaged or corroded CAN wires
  • Poor ground connection
  • Failed Control Module
  • Water Damage

Troubleshoot BMW CAN Network

Read / clear CAN Network Fault Codes.

If you are experiencing problems, reading fault codes from the CAN Network is a good starting point. If any code is showing PRESENT status, the problem needs to be fixed before the code can be cleared.

What you will need

A diagnostic scanner can read, clear, and perform bi-directional tests on BMW vehicles. You must verify that your scanner supports your BMW model and year. Full system scanners known to work on BMW vehicles can range in price from $150 to $ 800.

The YOUCANIC Full System Scanner can read and clear fault codes through every control module of your BMW vehicle.

bmw YOUCANIC SCANNER

These are only a few examples. Many diagnostic scanners allow you to read and clear BMW CAN Network fault codes.

Procedure

  1. Plugin the OBD-II scanner into the diagnostic port under the dashboard.diagnose-bmw-CAN-Network-fault-code-via-obd2-port
  2. Turn on the ignition; don’t start the engine.turn-on-bmw-ignition-to-read-CAN-Network-fault-codes
  3. Turn on the scanner and select your BMW chassis. Next, Select the Control Units menu.bmw-CAN-Network-control-unit-reading-codes
  4. Select Body then CAN Communication Analysis.

Once you enter the CAN Network, you can do the following.

  • Read Codes from CAN Network

CAN Network Fault Codes

Hundreds of fault codes can be related to the BMW CAN Network. Below are a few examples of codes stored in the BMW CAN Network.

  • CDA9 – DME Message A/C Request
  • E5C4 – CID K CAN wire fault
  • E71E – IHKA Message Torque
  • FFFF – CAN SYS Communication Fault

These fault codes will show during network analysis and be stored in the corresponding control unit.

We hope you find the BMW CAN Network Problems guide helpful. Check these troubleshooting and repair guides for more help on your BMW.

Additional Resources

  1. CAN Bus System and Technology – BMW Motorrad UK
  2. How to Diagnose a CAN Network – AA1Car.com
  3. Investigations on a BMW X5 Can Bus system – techtalk.ie

Author

  • Rushit Hila • ASE Certified

    Rushit Hila, an ASE-certified engineer (G1 Automotive Maintenance and Repair), brings over two decades of hands-on experience in the automotive world to his writing. With a strong educational background, including a Master of Science in Engineering and a Bachelor of Science in Engineering, he has honed his skills and expertise through years of practical work. As a respected authority in the field, Mr. Hila is dedicated to offering insightful and valuable content that resonates with both vehicle owners and mechanics.

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