For the Volt/Ampera, I think we've now got GPS location, altitude and heading (from OVMS GPS, not from the car), VIN and SOC (auto-ranging).

To make this useful, we need:

Whether the car is ON or OFF.
Whether the car is charging or not.
Speed
Estimated / Ideal ranges
Temperatures

Perhaps we need to get inventive? For example, if we know the car is off, speed is zero, and energy is going into the battery we can assume it is charging. If we see the car charging, then energy going into the battery is zero (or goes negative) for a time, then we can assume the charging has stopped. We can even alert if that happens and the battery SOC is not close to 100%.

Previously, it was mentioned that speed was available on:

3E9 Bytes 1-2 Speed 1/100 MPH 55MPH would be 5500 (0x157c)

Assuming the speed is ok, I can add that. But, any ideas about the other messages?

Regards, Mark.