Backup file

How-to use

Régis Thomas avatar
Written by Régis Thomas
Updated over a week ago

What is a backup file?

The backup file contains all the memories of the MCU.
The extension used is .zip or .bak. It can be decompressed with any decompression software that supports .zip format (e.g., Winzip, 7zip)

This file is automatically saved during boot or bench read in the "AutoTuner ECU backups" folder. This folder can be accessed by opening the Windows File Explorer and pasting the following address:
%userprofile%\documents\Autotuner ECU backups\
( The Windows File Explorer can be opened by using the keyboard shortcut "Windows Key + E" )

Maps are usually found in iflash0 or iflash1. These are variable pieces of data that occupy only a part of the memory, the rest is code to make the computer working.

As part of a boot or bench tricore reading we find:
* iflash 0
* iflash 1
* dflash 0
* dflash 1
* (eflash) if the MCU has an external flash memory

In the context of an OBD reading, no backup file is saved.

The backup file has two functions:

  • Return a vehicle to its original state

To do this, the user has the option to directly write the backup file within the ECU.

The slave user has the option to write the backup file on his own initiative without intervention from his master.

  • Edit data not related to engine mapping 

Thanks to backup file, you can modify the data located outside the maps area.
Any modification made to a file contained in the backup file causes the modification of its checksum.
Therefore, if the data has been modified, the user must systematically correct the checksum before writing one of the files from the backup.

Backup files extensions


Master = .zip

ex :  20210223-100134-20190000-BMW-X3-2011-MSD80-Bench-backup .zip

Slave = .bak

ex : 20210223-100134-20190000-BMW-X3-2011-MSD80-Bench-backup .bak

How-to-use full backup file ?

1️⃣ Find the backup file in "Documents" > "AutoTuner ECU backups" folder

⚠️ For Slave backup, first of all, it is necessary to decrypt backup file following this procedure.

2️⃣ Extract the contents of the backup file using software that supports .zip format

3️⃣ Modify the required part of the backup (iflash 0, iflash 1, dflash 0 and dflash 1) but don't rename the parts

4️⃣ Perform the checksum correction individually on each part that has been modified

5️⃣ Create a .zip archive that includes all parts of the backup (iflash 0, iflash 1, dflash 0 and dflash 1)

Do not create a .zip archive of a folder that includes the different parts of the backup file. The different parts must be compressed together in a .zip format. When extracted, files must be located directly at the root of the directory.

To make sure your backup is ready to use, you can preview and compare the zip archive content with the zip archive content of the original backup. It must be exactly the same. Nevertheless, archive file size can be different.

Original backup content:

Updated backup content:

6️⃣ Write the updated backup file in the ECU

⚠️ For slave backup, it is necessary to crypt the updated backup file following this procedure.

Did this answer your question?