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Anyone experienced codes like these?

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Papa Bear

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a known issue is a wiring harness under the passenger fender can touch the exhaust and melt wiring. Its worth 2 minutes to look up from the ground just behind passenger fender, above the exhaust. seems a harness attacthment point can come loose causing all kinds of issues!

edit: this maybe a diesel only issue iirc
Ok I’ll go look now in this area and see what up.
Just looked and everything looks fine with those connections. Plastic sleeves getting somewhat crusty but that’s it.
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At first it does what it always does, all the lights and gauges you see in the first video. Then the second video shows what happens when the power steering goes out as well. This is a serious issue and could result in a fatal accident if it took place on the wrong road, during the wrong weather or with traffic on either side. If anyone has any helpful information I will gladly attempt to utilize it. Heading down now to uninstall and reinstall the auxiliary battery one more time. Here goes nothing!
 

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You replaced the batteries and it was fine for 400 miles and went nuts again?? You have a bunch of u codes as well as other codes. This is what I had on my Duramax. My batteries were on the low side, so the new batteries corrected all the u codes, abs, airbag and a handful of other faults. Most of the codes I had were power related faults of the modules.

In your case, you replaced the batteries already, how about checking the grounds? Obviously you have checked the fender ground. This really bites.
 

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I am having the exact same issue. It is intermittent and seems to be related to either wiring. One thing I have noticed is that I have no problems until I turn on the heat or a/c. Nice I do, everything starts going haywire after a couple of minutes. I have replaced both batteries, so batteries do not appear to be the issue…
 

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UPDATE: I finally got my appointment at the dealership yesterday March 23rd, and they attempted to check for codes...there were none active but they found several which were stored. This makes sense as I had cleared the codes 10 days earlier with my Tazer JL Mini (like I had done a hundred times before) and hadn't driven the Jeep much because I was traveling. Part of me hoped that the codes would come back after driving to the dealership so I could show them exactly what the Jeep was doing alas, it drove fine all the way down to the dealership.

I had sent them the videos, some of which I have shared on this forum for insight, and they reviewed them but couldn't duplicate them. They chose to apply the procedures from TSB 18-048-22, which I found was focused mostly on error code P0300 (camshaft issue) which wasn't applicable to my situation but the TSB also referenced P0456 which was a vacuum pump issue and I have had P0456 on occasion-just the code no symptoms. The fix according to the TSB was a software upgrade to the PCM.

I asked if they had checked the voltages of the two new batteries and they hadn't. I asked if they had checked the ABS sensors, they didn't. I asked if they had checked the grounds and wiring harness...they hadn't. So, they felt really sure of themselves and that the PCM update was the fix because all of the stored codes were communication error codes and didn't refer to anything more serious. I drove it home no issues so I'm waiting and seeing what happens over the weekend when I will be driving it a lot. I'll post updates as I get them.
 
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And then last night after 220 miles of driving…all the same codes. This is so damn bizarre! I pray no one else has to go through this and it’s really uncanny how I can’t find another example of this with any of my fellow Jeep Bros. I mean I feel like if this is the only example then it has to be something simple:
New aux and primary batteries CHECK,
Fuses all seated properly and working CHECK,
Visible ground wires in good shape CHECK.
Again it’s a U0121 and P0415 at the heart of this issue I believe because those have been present the whole way through. Anyone have any ideas? I’ll explore them and report back.
 
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I'm going back in this afternoon and the dealership will have the Jeep all day tomorrow to go through more possible causes. I'd like them to look at the batteries, the Star Can Bus behind glove box and the wiring including grounds. Almost every reaction I have gotten has pointed to wiring and or/loose grounds. I hope they discover what the source of the problem is and fix it. I'll post up any updates to keep y'all in the loop.
 
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Well I'm not giving up on this even though my dealership is making it really difficult. The service manager sees me as a pest and doesn't really want my input on what to do to diagnose and fix. Thank goodness for the JLForum website which actually has a lot more of these issues happening. I was able to locate the part numbers which should help rule out or in the problematic parts. It seems to be the Star Can Bus behind the glovebox that is in a bad spot (glove box when closed seems to put pressure on the connectors and can even break them in the Can Bus banks). Here are the parts I am ordering and I'll let you know if installing these new parts fixes my issues. Obviously I will update you all if it works or doesn't. Also, I'm going to consolidate the info I found there into the most popular issues related to the Christmas Tree of lights, loss of power steering occasionally and the communications errors/MIL/CEL that are associated with this.
1. Can Bus connectors and banks behind the glove box Mopar part #s 68140647AA (Tan bank on right); 68321746AA (Green bank on left). My parts department at dealership didn't have these numbers until I gave them these and they believed you had to order the entire wiring harness in order to get these two banks.
2. Wiring harness for the disconnect sway bar motor (located behind the bumper and radiator, need to remove skid plate if equipped with steel skid plate to get a good look).
3. Wheel Speed Sensors (can get disconnected, wires break or too much grease/corrosion).
4. Batteries both auxiliary and primary (not ruling these out even though I replaced both of mine less than 1000 miles ago in March 2023 because Mopar has had numerous complaints of faulty batteries).
I hope that anyone experiencing issues like mine will have their mechanics look into these areas and that your issues are solved by implementing one of these fixes.
Check this link out to JLForums thread on this issue as it has a lot more comments than our gladiatorforum does at this time.
https://www.jlwranglerforums.com/forum/threads/dash-lit-up-loss-of-steering.75531/page-3
 
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Dealer installed the two Can Bus banks behind glovebox today and said everything looks good now, no codes! I’m going to test drive it this week and see if it all holds up. Will report back later!
 

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I'm currently dealing with this issue, as of two days ago. It is incredibly frustrating.

My biggest issue is that I also get an AutoPark issue, and the transmission is locked in Park after I start the truck. So, I have to shut it off and restart it a bunch of times, swear at the Jeep a little, and then eventually it starts up with only a few DTCs and I can shift into gear.

I also thought it was my Tazer, but I get the same behavior with and without the Tazer.

I ordered Can Bus part 68321746AA as indicated on the JL forums, I hope that's the fix! Really would like to avoid a trip to the dealer as many folks don't seem to have luck at dealerships with this issue.
 

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Can Bus part 68321746AA was the fix! Issue went away for me (so far) and it only cost $60 with no trips to the dealer - which is good because I'm out of warranty.
 

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Can Bus part 68321746AA was the fix! Issue went away for me (so far) and it only cost $60 with no trips to the dealer - which is good because I'm out of warranty.
How's it going??? Return of any errors??
 

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So far so good for me - no more errors. Fingers crossed this was the permanent fix!
 

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So similar, this was my Saturday..... Dealer just got done today 4/25, found nothing but maybe loose star connection behind glove box. I looked at that part you posted. Does that vacuum pump cycle? it was cycling while in the driveway Saturday, with all my lights ablaze..... Drove home np power steering.
=======================================================
Note to dealer was......

Silver 2020 Gladiator Sport. 8/19 Sale


Started out as CHECK ENGINE Light then added ABS light. Cleared it.

Week later, Friday, 4/21. Check Engine Light

Saturday AM, forgot to reset. Drive to Goodwill and landfill

4/22 - While in 18 truck line at landfill, I put in PARK, Trans locked itself in PARK. Radio and Speedo Blipped. Then Orange Check Engine light, Orange ABS light, two Orange Traction Control lights. Orange Service 4WD light. Service Shifter Message, RED Brake light in dash. There was another ABS Message, but I failed to get it.



Turned off engine, I restarted and was able to get in gear, NO POWEER STEERING. Got through line.



Drove home with all lights and no power steering. Engine and Trans Temps were good, oil pressure was good, Battery showing 14.1 while driving.



At home, scanned for codes. In this order

U0121

U1110

U1120

U11BC

U12AB

P057C (Brake Pedal Sensor Circuit Low)

U11BF

U0001 High Speed Can Communication Bus

P0000

The motor/compressor under the alternator, behind the radiator/Fan, was cycling. It connects up to the brake booster. Making sounds, I have a video.

I cleared codes, drove 20 miles, they have not returned. I tightened POS and NEG. Battery is showing 13.5 on multimeter. Both batteries are 8/2019 truck purchase.

Great reliable jeep. No problems. Steering gear replaced. Gas tank sensor replaced? Drives like a 2023 Grand Wagoneer.
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