I plugged a Bluetooth OBD II Sensor into my car and downloaded an app, it lets me see all of the detailed info on my car. The coolest info is seeing the battery voltage and resistances between cells and shit
When my battery melted I was able to show the tech exactly which cells had failed, he took 2 mins to check and came back with "yup it was those 3"
OBD2 is federally required for all cars sold in the US. That doesn’t mean it has to be useful though, it just has to say if there’s any emissions failures really which don’t apply to EVs.
The OBDII standard requires a standardized port with a standardized network using a standardized language, and what data must be available to monitor.
So every car with OBDII has all engine control or emissions related data available. What is not required to be standardized on an OBDII system are non-emissions related data, like what the climate control module is saying.
It is not just a way to get the standardized code for a check engine light, you can also see the data for that code like the sensor reading and sensor voltage.
The rest of the data on the canbus should be required to be disclosed publicly by manufacturers, instead of needing homebrew or 3rd party deciphering to understand all the data that is on the network.
While they are at it they need to come up with a mandated industry standard for assisted driving so that cars know that other cars are there and slowing down or speeding up, similar to boat AIS. Two way AIS helps a ton with collision avoidance and we really need a single standard for the whole car industry.
One of the issues I've had in the past, but the community quickly solved, was that my vehicle had a port, but used different parameter IDs than an ICE vehicle would. And those IDs weren't really documented, obviously. So while it provided values for the emissions and trouble codes required by regulation, they were obviously not useful. The values you would want were manufacturer specific, which every manufacturer uses differently.
It'd be acceptable to me if the manufacturers provided the necessary definitions to scan tool manufacturers, much like they do for ICE vehicles. But the perfect solution would be a requirement to publish the definitions and any necessary formulas for any vehicle sold in the US, retroactive for all vehicles already sold as well. There would be some hard lobbying against that effort, but it would be a HUGE win for consumers and repair shops.