Originally Posted by Sniper
Originally Posted by Andrewh
it isn't seeing the cleared codes.
I forget the term, but some thing shows not ready till after enough driving cycles or distance and that shows the codes were cleared recently or the battery was disconnected.
either way, as long as I can see that, I know that a code won't trip again till after that says ready, and I know not to dig any further in that car.

so as long as any scanner will show it, then I am good, just making sure I don't have to spend a certain amount.
the one above says check i/m readiness. I just want to make sure that is what I am looking for.


Those are the OBD2 Readiness Monitors. Those will clear and have to be rerun before they pass. A good reader will tell you what state they are in.

https://www.obdautodoctor.com/tutorials/obd-readiness-monitors-explained/


Exactly. Any time codes are cleared or battery is disconnected all the monitors are reset to "not run" status. Specific criteria need to be met in order to get all the monitors to run, complete and pass/fail. Mode 6 will tell you monitor status but not all code readers will show mode 6(they should but not all do)