If you sniff the network on a modern GM vehicle, the odometer is routinely broadcast. I believe it's broadcast in 1/10's of miles or kilometers.
Since you're looking for "miles travelled since the OBD was connected" then all you have to do is grab that value once at the beginning, and once at the end and subtract the first from the last.
This should be quite trivial, if you have any problems, post back here. I'll subscribe to this thread.
Hello, I am a newbie and am interested in trying to figure out how to get odometer information from the OBDII port. I am working on a Masters project for something I am designing. This doesn't have to actually be built, but it should be rooted in reality.
I have searched and seen that people haven't been able to get the odometer information out of the device. I am somewhat surprised. I see that the "Distance traveled with malfunction indicator lamp (MIL) on" is available and the "Distance traveled since codes cleared" is available. I am surprised with all the software available for the OBDLink Scan Tool that someone hasn't derived that function. This device is great because it datalogs through a USB cable.
I've researched the ScanGaugeII and it is supposed to give you odometer functions. There is no datalogging or output to pc capability I believe. I called their tech support and they said that if you don't reset the machine you can have the mileage continue forever (until the hex limit runs out).
I don't need the current odometer reading. I just need the distance traveled from the time the OBDII device is plugged in. Software can take care of the rest. Any software gurus want to try their hand.