What does a 'Permanent' DTC code mean?

I found a P0102 under the Permanent header in my OBD scanner display... What does 'permanent 'mean? I was able to clear the other code for a DTC I created. I haven't found the cause of this MAF sensor crct low fault yet, possibly a wiring issue, but am curious about the ominous 'permanent' label ....

 

It's a code that indicates a problem w/the vehicle's emission control systems and cannot be cleared by scan tool or by disconnecting the negative battery terminal.

It ends up being stored and 'active' w/in the vehicle's obd system and will remain in the vehicle's memory until the underlying issue is resolved. Once the issue is fixed, then the code will self-clear essentially and be removed from the OBDs memory.

These types of codes were put into place about 15 years ago to assist various states in dealing w/emission related issues during inspection. In other words if you are somewhere that requires a 'smog' or other emissions based test, you'll fail the test until you've resolved the underlying problem.

 

You turned on your truck while the MAF sensor was unplugged?

 

Thanks for the great explanation. Any ideas on where to find the electrical/wiring diagram for the MAF on a 2016 5.7L ?

 

hmmmm... I don't but, maybe @RainMan_PNW knows

Give him a few days to respond... He's had a very busy week and may be offline enjoying his weekend, but if anyone has that it would be him!

 

https://www.backyardmechanic.org/pending-vs-stored-vs-permanent-obdii-codes/

Quick google search:
They were added to the ODB standard in 2009-2010 to prevent clearing persistent codes before an emissions check. It indicates a persistent “stored” issue that is one flagged by the manufacturer as needing to be stored as permanent until the issue is resolved and stays resolved for a certain number of drive cycles.

 

Derp
I should read the whole thread…
Wiring diagrams are linked in my signature - on a phone turn it sideways to see the signature.
Off the top of my head, not sure which circuit you’re looking for, but you should be able to text search in most PDF reader software.