What could the issue be? Monitors not ready!!!

EP4

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Hey all,
2012 rubicon 79k miles

Went to get car inspected, failed due to the notorious “fuel system not ready” all monitors green, except for fuel system! Upon doing research i found this is a common issue, and the fix is to get the PCM updated/reflashed.

Did this, and now all monitors are green, fuel system monitor is green.. but OXYGEN monitor is now showing “not ready”

I have no check engine lights, the jeep runs great, it’s like i traded fuel system not ready, for oxygen sensor not ready.

Has anyone had this issue before? I’ve driven almost 200 miles since the PCM reflash, I’ve followed drive cycle instructions such as idle for 5 mins, accelerate to 30-40mph, etc.

I can’t seem to get oxygen sensor monitor to “ready” weird thing is, before the reflash, this was at “ready”

Any help or insight would be truly appreciated!
 
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BigAL07

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I read most common problem is weak battery. If over 4 years old replace.and rerun cycle. Sensitive to glitches. Clean terminals and grounds
 
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BigAL07

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Would not think so.BLACK JKU should chime in shortly. He is extremely good with electrical issues. Wait for him to reply before you do🍺🍺
 
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BLACKJKU

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Doing the ECM/Battery reset shouldn't cause any problems with your reflash. Who did the reflash, the Dealer?
 
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EP4

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Doing the ECM/Battery reset shouldn't cause any problems with your reflash. Who did the reflash, the Dealer?
Yes the dealer did a reflash/software update. That’s what they said

Fuel monitor went to ready before i even got home. Evap and O2 were not ready, Evap became ready yesterday around 70 miles.

Drove like hell today, did all the drive cycle recommendations. O2 still says not ready.
 

BLACKJKU

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Yes the dealer did a reflash/software update. That’s what they said

Fuel monitor went to ready before i even got home. Evap and O2 were not ready, Evap became ready yesterday around 70 miles.

Drove like hell today, did all the drive cycle recommendations. O2 still says not ready.


If you paid them money for doing this i'd go back and ask what's the problem with your work?
 
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EP4

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If you paid them money for doing this i'd go back and ask what's the problem with your work?
I paid them to reflash the system as that was the known remedy for the “fuel system monitor not ready” issue.

It fixed the issue, but now o2 is not ready.

Called them and said, we have to “diagnose” and then possibly change out sensors..

Frustrating
 

BLACKJKU

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I paid them to reflash the system as that was the known remedy for the “fuel system monitor not ready” issue.

It fixed the issue, but now o2 is not ready.

Called them and said, we have to “diagnose” and then possibly change out sensors..

Frustrating

If it was the O2 sensors they would be giving you a CEL. Is your CEL light working?

Take your Jeep to a Auto Parts Store that does free CEL checks.
 
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EP4

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If it was the O2 sensors they would be giving you a CEL. Is your CEL light working?

Take your Jeep to an Auto Parts Store that does free CEL checks.
No CEL or codes, i have a pretty good OBDII scanner.. i actually just reset all the monitors via scanner.

Hopefully it was a glitch. I’m going to try and go thru all the drive cycles again, will update!

If anyone had this issue before after the PCM reflash, please update!
Thanks!!