Codes but no CEL?

hear

Can't type
Original poster
Lifetime Supporting Member
Joined
Oct 18, 2020
Messages
6,089
Location
Prosper, TX
For no good reason, I plugged my code reader in just now and found P0303 & P0441 present. Reset them, they came right back. I've already read the troubleshooting threads on these 2 codes so I think I have a plan for how to address them, but why I'm posting this is that the CEL light hasn't been on since I corrected a CPS issue the night I bought the jeep. (well, occasionally it comes on briefly after a hard stop when the oil pressure drops but then it comes right back up and the CEL light goes off again).

I'm certainly no expert, but is it out of the ordinary to have such codes being thrown without the check engine light coming on? I mean, I guess most people wouldn't even know if this was typical because who checks codes if the light isn't on?
 
CARB OBD2 monitoring has two-trip logic for most codes - in other words a code needs to assert on two different power cycles before the light will come on. If the code is generated once it's put in 'pending' status, if it's generated twice it goes to 'current' status which triggers the CEL. Does it say pending or current on your reader? Some of them display that variable, some don't.
 
Hmm, at least one of them did say pending. I’ll check again next time I’m out there.