Skip to main content
This guide discusses the BMW telematic control unit (TCU) module and how to diagnose it.

Table of Contents

BMW TCU module is located in the trunk area, but fault codes stored in the TCU can be read via the OBD-II port under the dashboard. BMW TCU module contains the Bluetooth module.


A defective TCU module can prevent your phone from connecting to the car via Bluetooth. TCU and your Bluetooth handset communicate with each other via the antenna connected to the TCU.

When your BMW TCU module fails, you may notice:

  • SOS malfunction message on iDrive screen.

How to Diagnose BMW TCU Module

If you are experiencing problems, a good starting point is to read fault codes from the TCU module.

If any code shows PRESENT status, the problem needs to be fixed before the code can be cleared.

What you will need

For this step, you will need a diagnostic scanner capable of reading and clearing codes from the BMW TCU module.


These are general instructions and may vary depending on the diagnostic scanner model you use to troubleshoot BMW vehicles.

  1. Plugin the OBD-II scanner into the diagnostic port under the dashboard.diagnose bmw TCU fault code via obd2 port
  2. Turn on the ignition; don't start the engine.turn on bmw ignition to read TCU fault codes
  3. Turn on the scanner and select your BMW chassis. Next, Select the Control Units TCU control unit module reading codes
  4. Select the TCU control unit list
  5. Once you enter the TCU module, you will be able to do the following.
    • Read Codes from TCU Module
    • Clear Codes from TCU Module
    • Perform Adaptations, Activations, Tests

When purchasing a BMW scanner, verify that it supports your BMW model and year. Full system scanners known to work on BMW vehicles can range from $150 to $800. Learn more about popular BMW scanners here.

Buy BMW TCU module

You can buy a BMW TCU from your dealer or purchase a BMW TCU Module on eBay online. Note that the TCU module needs to be programmed and coded to match the options and your VIN. Keep in mind that the Bluetooth code used to pair your phone with the car is stored in the TCU.