3 ms·
In recent cases, these defeat devices have all been for NOx. NOx is reduced in the catalytic converter, unless there is too much oxygen in the exhaust. The de
by hwillis 9y ago
In recent cases, these defeat devices have all been for NOx. NOx is reduced in the catalytic converter, unless there is too much oxygen in the exhaust. The defeat devices turn off behavior that limits exhaust oxygen.
Every car comes with an oxygen sensor, which could be used to infer how much NOx is being emitted. So, the solution may actually just mean a standardized little microcontroller that reports directly through the ODB port on how much oxygen has been in the exhaust. If it's sufficiently simple it shouldn't be beatable.
- rjsw 9y agoYou don't really want to have to plug something into the ODB port. I have been a member of the ISO committee that standardized ODB-II and related stuff. I remember the representative of one OEM suggesting that they expected at least California to require emissions testing in real-world conditions at some point. This was about 15 years ago. There was the expectation that in the future the vehicle bus would have a short-range wireless gateway so that you can link the brakeing systems together of cars in a road train. With this in place a country could set up roadside boxes to read out the current emissions values. With the change in usage of mobile phones over that time you could pick a different mechanism today. I guess you still have the issue of potentially needing to prevent cheating, the OBD-II PID values are in a sense "translated" from the OEM specific data on the CAN bus.