I was getting a low voltage terminal 30 error in my ECU, which I diagnosed using my genuine Ross-Tech VCDS cable.

I bought a second-hand ECU on eBay with the same part number (8N0 906 018 BB) for $100 USD. Using a CH341A programmer and ASProgrammer software, I read the ST95040 EEPROM from my original ECU and transferred the data to the donor ECU.

After installing the donor ECU, my car runs fine and the low voltage terminal 30 error is gone.

My original ECU had been tuned by a previous owner with a GIAC tune. The 29F800BB flash chip is mounted on a daughterboard, and there’s a square chip underneath the daughterboard with its identification number sanded off. I’ve learned this is an encryption socket. From my research, if I were to read the flash chip directly with something like a TL866, the data would be encrypted.

Following a tutorial I found on this forum, I hex-edited the Galileo 1260 software so my generic red FTDI232-based VAG-COM KKL cable would work with it. I soldered an OBD2 female port to my old ECU, put the ECU into boot mode, and read the flash. I believe the read was successful, but I’m not 100% certain.

When I ran ME7Check on the file, it reported 1 checksum error. According to the ME7Check GitHub page:

"Many tuners modify the CRC/Checksum algorithms to discourage modification of their tunes. ME7Sum most likely will not detect such modifications."

I’m hoping this explains the checksum error in my read of the original ECU’s tune.

Next, using the NefMoto flashing software, I first read the stock tune from my donor ECU, then programmed my original ECU’s tune onto the donor ECU. The car now runs and drives fine, except for a steering angle sensor mechanical error that I’m getting.

I don’t have any tuning experience, so I’d like your opinion on what I’ve done so far and whether there’s anything that could be problematic. If anyone knows how, could you check whether my tuned flash file is correct and not missing any data?

I’ve uploaded:

The stock donor ECU file

My original ECU tune file

An XDF file I found on this site for my ECU

Thank you.

Indeed, there's an RSA signature error in the 'GIAC' file.

Where is your own setting?