I gets stuck on StartDiagnosticSession, I get a positive response from sending the seed solution. I am wondering if this is maybe because I am starting an 0x89 diagnostic session before I send the seed (so I can use DDLI/WBLI). I'll try your suggestions as well as look into timing. Maybe I will build a sniffer, I have a lot of usb serial cables, and my software should even work with CH340...


Ideally this will support as many ECUs as possible. Once I have a fully functional program for my car's 518AK I will start looking into widening compatibility. I am trying to make the code as generic as possible.

While the change you made to the code makes sense, it doesn't actually work. This is because it affects the result of the if statement.


Thanks! I'll keep up with the updates, good to know they are appreciated.

Have tried that. Re-init works, but I still get the RequestPending (eventually it stops sending that and doesn't send any data at all).
After spending the first half of my morning playing around with that I decided to start writing a much more friendly API for interacting with KWP2000.
It's still a bit messy because I am doing everything in a loop (so order isn't obvious) but that will be fixed soon too.


Haha, to be fair, I did spend a good 15 minutes trying to figure out why your change didn't work 

Good to know, thanks. I should check that I didn't leave it in programming mode after I cancelled a flash read in Nefmoto. Once I got the bench harness working I boot mode flashed a stock file (the one from the 1.8t community thread) and then used the nef flasher to make sure the ECU was responding to kwp2000. I'll try doing a full readback and proper disconnect like this post says.

Reason for re-flash is that I have no idea what the previous tuners (used car, previous owner got a Unitronic tune) did but I know that they disabled reading over KWP2000... Made a backup of the tune for good measure, but my DIY noob tune already seems to be running much smoother than the OTS file (though slightly less peak load, but that seems safer...)  Maybe one day I'll map that bin and compare their changes with mine.

I don't doubt #1, given I am actually using logs of my own car. I am curious as to why the OTS tune idles rough (had no idea it was bad until I flashed a stock file, never been in a 1.8T other than my own) and partial throttle is so jerky. I can guess knowing what I do now, but it would still be nice to see what it actually is. Anyways, not going to bother doing that unless I truly get bored, which will be a long ways out given the two software projects I've got going on now.

Well you were right. Even the nefmoto flasher fails to connect with a programming session, exact same issue (tries, then times out). I'm a little pissed at myself for not trying this sooner, that's a lot of wasted debug hours. Oh well, so it goes with projects like this.

Edit: not actually sure what nameless mentioned is the exact issue anymore, but the nefmoto flasher does have the same issue as me.
Edit 2: seems the nef flasher successfully gets security access sometimes, but then when it tries to do a read the ECU reports that it doesn't have security access. I wonder if these issues are because of my DDLI security timeout hack.


That's really good to know before jumping in, thank you
I do forget sometimes that professional just means paid, not better.

That was the solution (which I eventually figured out when I saw only half my bench harness was plugged in).  I am now in diagnostics mode. I actually had to do a bootmode flash as well, and nefmoto still doesnt work. But at least my kwp2000 works!

Wanted to get my API looking nice before I started to work on the programming functions. Now everything is abstracted away to simple function calls instead of a messy loop. This API will undergo a lot of changes later on, but the way it is now makes it easy to do quick development.

Rudimentary flash reading in programming mode works now.