I've managed to revive it, for those that don't know if you kill the power for the ECU you can connect to it for the first boot only.

Interestringly WinOLS 1.721 claimed to have done the checksums, I've now used Kess which claims checksum correction but I can only start the car once after a flash, once the dash is off and on again then it fails to boot.

With the standard file it flashes then starts everytime.

This is what I am confused about.. The file was altered in 1.721 as I don't have the right dll for 2.24.

Claimed checksum was fine, flashed file with MagPro2 clone as it was at home helping a mate and it wouldn't start up after and wouldn't talk to me anymore.

After working out the battery check I attempted to flash with a genuine Kess V2 Master and still had issues. Kess claimed it could correct checksums. I then read out the file that Kess V2 wrote and it was different from what WinOLS 1.721 produced.

I then got desperate and used ECM to checksum and they claim its correct.

So perhaps it's not checksums, but something else? I worked from the original binary off the car which has the same HW SW numbers as the version commonly available online but a slightly different binary layout as it seems to have a different SW UPGRADE number. But this isn't a problem as I ported the maps I needed easily enough and for now I was just requesting a bit more load to check what tools worked and get a feel for where to start.

Anyone experienced with Porsches know of any issue I could be running into here?

Hmm perhaps i should downgrade it to the older version supplied here