Corvette CCM Reverse Engineering Anyone?

[NomakeWan]

That's odd about the female connectors; normally it's the male connectors that are gone. For example, you can still to this day buy the female (car-side) connectors for the HVAC Programmer and the PKE Module. But the male connectors, for someone who might want to, say, make their own modern HVAC Programmer or replacement PKE Module? Nope!

Anyway, confirmed your findings partially. The green connector is out of production and not available from any of my usual sources for harness connectors. The grey connector, however, can still be acquired from a few sources. But of course that doesn't really matter if you can't get the green one. It's really crappy too because there are other 32-way connectors in the exact same connector family that are readily available, just not these specific two. Damn you, Delphi/Aptiv.

As for my end, my first experiment with talking to the car was a failure with a minor success. The minor success was I did get my AVR to properly recognize all of the CCM Poll requests, so I at least wrote that part of the code correctly. The fail was I was unable to then transmit the proper response signal. Considering all I did was short together the RX and TX lines and jam them into pin 9, I'm betting it's my wiring at fault, not the code. I was hoping that just disabling the TX/RX functions by flipping the appropriate bits before changing whether I was receiving or transmitting would be sufficient but clearly not. I don't have time today to go grab the PNP transistors I need to build the more robust interface circuit because I'm busy with GTR stuff, but hopefully tomorrow I'll have time to go get the parts and build the new circuit.

[spfautsch]

Sounds neat. I'd be interested to hear how the speedometer functions. My guess would have been that the ccm uses the vss line from the pcm for that instead of aldl data.

Mind me asking what arduino you're using? Hardware or software serial? Around 2009 or 2010 I messed around with the mpguino project and got it talking to my VW over iso 9141. I recall building an op-amp setup for that, but I can't find the code. I know I have the parts and schematic stashed in an esd bag in my lab somewhere.