Hey Guys,

first of all sorry if I'm asking anything stupid. I just started to play around the ECU tuning a few weeks ago, so almost everything is very new for me.
I'm trying to modify the SW on the mentioned car in order to get rid of the DTC caused by the wrong lambda values (the system is already not stock and running w/o catalyst).

On the car already a tuned SW is running (not done by me, and I don't know the history of it), and mainly I want to use that SW as base. I found the necessary DTCs thanks to another clever guy:
P0420 - 1D61E6-1D61EA
0036, 0037, 0038, 0054, 0136, 0137, 0138, 0139, 0140, 0141, 2270, 2271, 2A01
1D61CA-1D61D1
1D6222-1D6224
1D620A-1D620D
P0423 - 1D6146

I modified the existing binary considering this wiht WinOLS, but during the MPPS write the car does not accepting it. As a verification I tried to upload the binary I got from the read, but also without any success. Beside these I have the original stock binary as well and that is flashable and working. I assume this shall be some kind of checksum problem, but I'm absolutely not sure.

Can any of you please help me out here? What am I missing?
You can find here the files I tried to use (and mentioned).

Thank you for the inputs in advance!

Short update in the topic:

The checksums are seems to be incorrect: in the original file, the WinOLS is able to find 70 checksums, but the file I read from the car (the already tuned one) only 8 checksums are found. I not yet know the reason behind it. So any idea can be good! :)