Hi Scott, can you check that the data from ID 32A is somewhere else in your logs? in mine 32A is always zero. We have here no OnStar. But i have the full package including Navigation. Bye michael
The latitude/longitude conversion is almost the same as what you have for the Tesla, with two exceptions -- changing the 2048 to 1000, as noted, and the accounting for negative numbers is different. It seems that the number the Volt supplies is a 31-bit signed integer. The easiest way to handle that, I think, would be to add "latlon = latlon << 1;" before checking for <0, and then "latlon = latlon >> 1;" afterwards. Running the code you have with those two changes seems to work fine.
The bad news is that I have checked all my log files (I have been logging almost all the time I have driven for about 8 months now), and the CAN ID 32A (latitude/longitude) has never shown all zeroes. If the GPS data is unobtainable, I believe the car reports the most recent reading. The GPS data comes from the OnStar system, so I am thinking it may only provide the data if the OnStar service has been activated, which could be a problem for owners outside of U.S/Canada.