RomRaider

I'm trying to define an old OBD-I JECS rom. Using ecuEdit I've found quite a few maps based on patterns alone. I also have the ROM code for this ECM, so I can sort of understand what it's doing. I just can't seem to make sense of how the ECM knows what conversion to use to display voltages or amperages as something we can easily distinguish. The information has to be stored in the ECM somewhere, are there any clues as to where it "should" be? What it might look like? Or where it might be based on a denso ECM?

Thanks.

if you can find details about the older SSM and obdi protocol and find those routines in IDA then you could figure it out from there.

The page at http://www.vwrx.com/index.php?pg=selectmonitor has some conversion factors used in old SSM-I ECU RAMs.

If you want to pursue merchgod's suggestion, you can download the source code for an SSM-I logger at http://www.graphics.cornell.edu/~v/b10scan/.