Foxflash Failed to Write BMW MG1CS003 Solution

By | January 31, 2023


I am trying to read and write this BMW MG1CS003 ECU with Foxflash.  Tried to write modify file, and failed, then tried to write original file, failed at the same place. Also tried with voltage v13.4 and failed.

Foxflash BMW MG1CS003 2

Foxflash BMW MG1CS003 3

iECUTOOL Technican Solution:

New ECU’s have clever Voltage protection, during diagnostics or programming voltage is expected to be 13v or less – above that is considered engine running condition.




Turned the voltage down from 13.9 to 12v and tried again. Wrote no problem. It worked without issue with 12v. Fox flash did the job in the end.

I had a lot of issues with Vauxhall trying to use other tools because of Tprot, but Fox did the job first time.

Foxflash BMW MG1CS003 1