Rewrite Porsche BCM 2M25J CPU by Xhorse VVDI Prog

Managed to replace/ change Porsche 2M25J CPU on BCM, with back-up of original D-FLSH and P-FLSH in Xhorse VVDI Prog programmer.


I first tried it myself.

Rewrite partition for 2M25J

VVDIPROG-v4.3.1-replace-Porsche-2M25J-CPU (1)

If the D-FLSH is 16K,set EEE partition as 8

VVDIPROG-v4.3.1-replace-Porsche-2M25J-CPU (2)

If the D-FLSH is 32K,set EEE partition as 0

VVDIPROG-v4.3.1-replace-Porsche-2M25J-CPU (3)

Partition division complete. Then write the backup D-FLSH, and then P-FLSH

Finish encryption in the end. Porsche encryption byte: 7D

VVDIPROG-v4.3.1-replace-Porsche-2M25J-CPU (4)

VVDIPROG-v4.3.1-replace-Porsche-2M25J-CPU (5)

However, the BCM cannot work at all. Failed to read data and decrypt.


Discussed with the engineer, i adopted the method below:

Step 1 – completely clear the encryption

Select the device and clear the encryption fully

VVDIPROG-v4.3.1-replace-Porsche-2M25J-CPU (6)

Then CPU is all cleared. Again divide CPU partition. set the partition as 8


Step 2 – Write D-FLSH

Some data to modify before writing D-FLSH

Find out Line “7FF00” and replace “7D” with “FF”, then write CPU

VVDIPROG-v4.3.1-replace-Porsche-2M25J-CPU (7)

Then perform encryption

VVDIPROG-v4.3.1-replace-Porsche-2M25J-CPU (8)

When all above is complete, decryption and encryption-reading work ok.


So, a good device needs a good way to perform it for the best benefit.

Hope this helps.