[m5james]

Originally Posted by JoeyBimX5din

I don't think auto clear is the right way to describe it. I do not know specifically how it works on our BMW's and it may function exactly the same way as I know it. I can talk about something you know about, Ford EEC architecture. To oversimplify the process, the downstream o2's (rear) sense if your catalyst is functioning based on the amount of oxygen passing through the sensor vs your upstream o2's (front). Most Ford tunes will set the computer to see its ideal number all the time for the downstream sensors, telling the ECM, yes the catalyst is doing its job. In the mid 2000s when everyone was afraid of online shopping you could find downstream MIL eliminator o2 sensors pre wired to keep your check engine light off if you had a catalyst issue. They sold for almost all models. Now, I think they have all gotten scared by laws and that pesky EPA.

Now I don't know if burger has in the past done other things in there tunes to keep a check engine light off, and this may be what you are referring to.

Auto clear is howthat BMS described it. I'm running an older firmware on my JB4 to keep this option enabled via the steering wheel controls.