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I think it would help if there was a list of key OBD values including some details of confidence level and how the value has been verified.
Some items, such as odometer and speed are quite easy to verify, but others can be rather tricky.
As an example, I have done some work on the iMiev OVMS code and one of the key items there is a set of values that appear on 4 PIDs with a number that moves from 1 to 12. This "seems" to give 88 numbers that seem to be about right for battery voltages * 100. There are also 64 values mixed in with these that look very much like cell temperatures in Celsius plus 50 and move up when the battery is charged or used and down when rested. There are 88 cells in the battery pack so the voltages make lots of sense. It also makes sense that there are temperatures sensors throughout the pack, but why 64 and not 88 or 44? Also, the temperature may be offset by 48 rather than 50 or it could be (Fahrenheit / 2) + 20. In fact I have noticed that -55C seems to be a common "low-end" temperature for digital temperature sensors and I often think the temperatures I read are a few degrees higher than I would have expected - so maybe it is Temp + 55.
Some items, such as odometer and speed are quite easy to verify, but others can be rather tricky.
As an example, I have done some work on the iMiev OVMS code and one of the key items there is a set of values that appear on 4 PIDs with a number that moves from 1 to 12. This "seems" to give 88 numbers that seem to be about right for battery voltages * 100. There are also 64 values mixed in with these that look very much like cell temperatures in Celsius plus 50 and move up when the battery is charged or used and down when rested. There are 88 cells in the battery pack so the voltages make lots of sense. It also makes sense that there are temperatures sensors throughout the pack, but why 64 and not 88 or 44? Also, the temperature may be offset by 48 rather than 50 or it could be (Fahrenheit / 2) + 20. In fact I have noticed that -55C seems to be a common "low-end" temperature for digital temperature sensors and I often think the temperatures I read are a few degrees higher than I would have expected - so maybe it is Temp + 55.
