Tips about BMW can’t Restore Encoding

BMW FEM/ BDC system may encounter some problems after matching the key. Here is an actual operation case to describe the whole process and solution.

We take 2015-year BMW X5 BDC system vehicle as an example.



Connect the test platform to the BDC to read the key information. It shows that this version does not support preprocessing, and the device needs to be programmed before preprocessing (this version is estimated to be an older version, and the next version needs to be upgraded to proceed to the next step).

We first back up the code and use VVDI BMW tools (you can also use other BMW programming tools) for programming.


The programming process was relatively smooth and was completed within 5 minutes, but the attempt to restore the code after the programming was failed. Repeated coding from the platform will prompt failure. The device recommends coding on the car.


At this time, the process of matching keys is not over yet, so I want to pre-process the BDC before getting on the car for coding. So read and write data to 95256 of BDC, write service mode data programming and finally match the key smoothly. Finally, the BDC is loaded into the vehicle for code recovery. However, using the device to directly restore the encoding still shows failure, and the backup encoding file cannot be written into the BDC. And it is also impossible to restore the encoding when changing the equipment of several other manufacturers.


Use Xhorse VVDI BMW to try. After connecting to the BMW tool of VVDI, after automatically diagnosing the vehicle information, perform coding calculation on the front module BDC (do not select the BDC gateway), and then write the code.



When written successfully, everything in the vehicle returned to normal and the vehicle did not report a fault, and the entire work was completed.

Summary: Some special versions of FEM BDC codes cannot be restored on the platform. You can install the FEM BDC on the car for restoration. If it cannot be restored on the car, you need to use a programming device for coding calculation and writing (IMMO matching device, and programming device may process codes differently). Therefore, as long as the code cannot be restored, if it is not a hardware problem, it can be solved by replacing the corresponding programming device.