P0456 Code

[TexasIronMan]

Hey all! I drive a 18 JLU with the 3.6L. Got in my Jeep this morning and engine light came on. Went and got it tested and it was pulling code P0456 (Evap Emission System Leak Detected, Very small leak). I did replace the aux battery about a week or 2 ago. Any ideas on what this could be?

As well, it's showing the drive train is locked?

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[Fonzilla85]

Check your gas cap, might not be fully closed. Aux battery should have nothing to do with it.

 

[mwilk012]

Check your gas cap, might not be fully closed. Aux battery should have nothing to do with it.

Nope, it's a known software issue on the 18's.

Clear it and see if it will stay gone, if not, hit up the dealer for a software update to the PCM.

 

[Fonzilla85]

Nope, it's a known software issue on the 18's.

Clear it and see if it will stay gone, if not, hit up the dealer for a software update to the PCM.

 

[Leisure Freak]

Had the same thing happen on my 2019. After changing main battery (aux was previously bypassed) got the P0456 a few hundred miles later. About 300 miles later it auto reset/cleared itself. Another battery power disconnect 2000 miles after that and it repeated the issue. When asking for the PCM update the dealer claimed No Knowledge until I told them what it was and even then said my still-valid powertrain warranty would probably not cover it- It did....
PCM Update number-68440959 - PCM Update to address nuisance P0456 code.
They did it but warned they aren't sure it will always avoid the P0456 when power is interrupted since it sees the P0456 code as a default for any PCM fart encountered. Haven't had an incident to verify that yet.

 

[bcupton]

There are days I long for the times before we had codes!

 

[The Meep]

Had the same issue about 3 months ago. Scanned and cleared it with my OBDII scanner, and it hasn't done it again.

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