2018 JLUR significant electrical issues

[Granite18jl]

I have a 2018 Jeep Wrangler, built July 2018, which started having electrical issues this past November (2022) and have gotten worse effectively limiting the use of my Jeep to near home, low risk trips (groceries, commute, but not airport).

The Jeep periodically (1 out of 5 trips) has what I can only describe as an electrical storm where all the dashboard warning indicators illuminate, power steering (sometimes) shut downs, "Service ABS" indicates failure, "Service Electronic Stability Control", "Stop/Start Unavailable Service Stop/Start System", "Sway Bar Disconnect Unavailable" indicates failure, "SERV 4WD", parking break light comes on (brake off), check engine light illuminates, airbag indicator light illuminates, , seat belt indicator (while wearing), AutoPark disables, ParkSense "Off", Blind Spot Alert "Unavaible", "Service Shifter", etc. Sometimes the engine fans spin up as if the vehicle is overheating.

This morning on my commute I had this occur and pulled off to the last parking lot before the interstate, as I did not want to drive on the highway without power steering. Once parked the first restart resulted in all the alerts presenting again, not sure about power steering as I was parked. Second restart had alerts and would not allow me to shift the Jeep out of "Park". I let it sit for a while and then restarted the Jeep with some alerts but with the ability to shift our of 'park' into 'reverse' and the power steering was working; thinking I should take advantage of what I had working I proceeded to work. The first time this happened I sat in a turn lane for 30 mins trying to get the Jeep running and out of "Park"

The jeep has spent 3 work weeks at the dealership with no success in resolving the issue. I am still under the 60K power train warranty but I was told that does not cover these issues, even though the alerts indicate multiple drive train issues "Service Shifter" and prevent the car from being reasonably driven, so I have paid hundreds of dollars out of pocket with no fix.

The Jeep is 4 years old, still under power train warranty, but is basically untrustworthy and therefore substantially unusable.
I'm the only one who rides around in it. My wife and daughters don't trust it. I can't drive my kids and other kids to sporting and recreational events.

The dealership has no ideas, they say they can see log events of what has happened but have no diagnostic error codes to indicate cause.

I am basically stuck with a $50,000 vehicle that no one knows how to fix, and I can't in good conscience sell. I've thought about trading it in but the next dealership will just pass it along to some unknowing buyer.

Anyone have any good ideas?

Okay so been dealing with the same issue for over a month on and off electric issues but it got so frustrating looking and looking for an answer I have done all no cost fixes so far.
1st. Push all fuses down under hood (30min)
2nd. clean connections I could reach under hood and in wheel wells. (2hours)
3rd. took glove box apart push all pins aka wires into place green can-bus (20mins)
4th eliminated the ess battery aka bypass ess (20 mins)
5th main battery replaced still under maintenance warranty 2 year old battery free $216 dollar Battery, with ess still bypassed (30 mins)
Seems as this might just be it but need like two full days of starting and stopping as well as driving to truly see if thats the real fix.
6th not done yet but waiting change Can-bus out for new one.

Dealers ALWAYS say “it is not the battery.” Yet two thirds of the time all the problems go away after YOU replace BOTH batteries.

I suggest you:

1. Make sure all the fuses are pushed all the way day, and all terminals are tight
2. Replace both batteries yourself. Go to Auto Zone or O’Reillys, at the parts counter give your vehicle year, make and model, and get two of their direct replacement batteries and change them yourself. This step fixed all the electrical issues I was having on my 2018 JL. If you are going to wait for the dealer to touch the batteries, you will die of old age
3. A number of JL owners have found that the CAN BUS connectors located behind the glove compartment became faulty. Replacing the connectors solved the Christmas tree lights situation

There’s a 99% probability that these three steps will fix your electrical issues.

Good luck.

i was in denial about the battery because both my Batteries where only two years old. Did four other fixes before I tried the battery seems as if it was the battery just have to drive for like three consecutive days to make sure because I couldn’t go two days before I had everything happen to my Jeep, and if that dont work Can bus next I already have the replacement just waiting to see whats next if anything at all.

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[janieo23]

I have a 2018 Jeep Wrangler, built July 2018, which started having electrical issues this past November (2022) and have gotten worse effectively limiting the use of my Jeep to near home, low risk trips (groceries, commute, but not airport).

The Jeep periodically (1 out of 5 trips) has what I can only describe as an electrical storm where all the dashboard warning indicators illuminate, power steering (sometimes) shut downs, "Service ABS" indicates failure, "Service Electronic Stability Control", "Stop/Start Unavailable Service Stop/Start System", "Sway Bar Disconnect Unavailable" indicates failure, "SERV 4WD", parking break light comes on (brake off), check engine light illuminates, airbag indicator light illuminates, , seat belt indicator (while wearing), AutoPark disables, ParkSense "Off", Blind Spot Alert "Unavaible", "Service Shifter", etc. Sometimes the engine fans spin up as if the vehicle is overheating.

This morning on my commute I had this occur and pulled off to the last parking lot before the interstate, as I did not want to drive on the highway without power steering. Once parked the first restart resulted in all the alerts presenting again, not sure about power steering as I was parked. Second restart had alerts and would not allow me to shift the Jeep out of "Park". I let it sit for a while and then restarted the Jeep with some alerts but with the ability to shift our of 'park' into 'reverse' and the power steering was working; thinking I should take advantage of what I had working I proceeded to work. The first time this happened I sat in a turn lane for 30 mins trying to get the Jeep running and out of "Park"

The jeep has spent 3 work weeks at the dealership with no success in resolving the issue. I am still under the 60K power train warranty but I was told that does not cover these issues, even though the alerts indicate multiple drive train issues "Service Shifter" and prevent the car from being reasonably driven, so I have paid hundreds of dollars out of pocket with no fix.

The Jeep is 4 years old, still under power train warranty, but is basically untrustworthy and therefore substantially unusable.
I'm the only one who rides around in it. My wife and daughters don't trust it. I can't drive my kids and other kids to sporting and recreational events.

The dealership has no ideas, they say they can see log events of what has happened but have no diagnostic error codes to indicate cause.

I am basically stuck with a $50,000 vehicle that no one knows how to fix, and I can't in good conscience sell. I've thought about trading it in but the next dealership will just pass it along to some unknowing buyer.

Anyone have any good ideas?

I am having the exact same issues with my 2018 Wrangler JL. My issues also started last year. It was at the dealer from 5/26-7/12 and they replaced my ABS module with hopes that would fix it and sure enough the problems happened again last night with my power steering going out while in motion. Both of my batteries were replaced last year as well.
Did you find any solution yet?

 

[ransom1]

I have a 2018 JL two door manual transmission. Bought it with 3500 miles in the spring of 2020 and have loved it...until May of this year. 42k miles and the power steering went out. Then the wipers and all gauges going haywire. Three separate trips to the dealer (who has been incredibly gracious btw letting me have a loaner for essentially 12 weeks). We've replaced the power steering module twice and the BCM too. I'm upside down $2300 and it's still not fixed. Now we are disconnecting the light bar and the bumper fog lights (which are both aftermarket) to see if that helps. Will keep this forum posted. I have had six Jeeps. Loved every one of them. But this ends my loyalty to this brand.

 

[janieo23]

I am having the exact same issues with my 2018 Wrangler JL. My issues also started last year. It was at the dealer from 5/26-7/12 and they replaced my ABS module with hopes that would fix it and sure enough the problems happened again last night with my power steering going out while in motion. Both of my batteries were replaced last year as well.
Did you find any solution yet?

The dealer replaced the power cord to the new ABS module on my most recent visit and I have drove it over 200 miles without issue so far. Fingers crossed this was it!

 

[ransom1]

I’ll ask if they did that on mine. Thank you so much.

 

[gahammerle]

I have a 2018 JL two door manual transmission. Bought it with 3500 miles in the spring of 2020 and have loved it...until May of this year. 42k miles and the power steering went out. Then the wipers and all gauges going haywire. Three separate trips to the dealer (who has been incredibly gracious btw letting me have a loaner for essentially 12 weeks). We've replaced the power steering module twice and the BCM too. I'm upside down $2300 and it's still not fixed. Now we are disconnecting the light bar and the bumper fog lights (which are both aftermarket) to see if that helps. Will keep this forum posted. I have had six Jeeps. Loved every one of them. But this ends my loyalty to this brand.

Replace the green canbus block behind the glove box. $13 on ebay and 10 minutes to replace.

 

[ransom1]

Thank you so much! Will definitely do this. So appreciative of the good advice here. Should have sought this wisdom 10 weeks ago. Will be replacing aux battery and green block and power cord for sure. And I will keep this forum posted.

 

[mwilk012]

There isn’t a “power cord” to the ABS module. They would have replaced the wiring harness connector to the ABS module. Or at least made that up so you feel better about it being fixed.

 

[ransom1]

Thanks for this qualification/clarification.

 

[cmb396]

Thanks, that is really helpful!

Any updates on this? OUr JLUR is doing the same thing. Dash goes into electrical frenzy, wont shift, power steering goes out, spits and sputters, etc. Sometimes, it will start to shift again, other times, you have to stop, put it in park to get it to shift regularly.
The dash always reverts back to the gauges screen no matter what you have it set on, once it starts flipping thru all the screens on its own.
I have replaced both batteries, new pcm, checked everything I know to check, and it still happens. Like you said, it's a $50k garage ornament atm! The dealer is not being helpful either, as they have no clue.
I had close to 30 codes, that spanned all over the place from gas cap, abs, shifter, lost comm with radio, evap pump, and so on.

 

[ransom1]

My dealer is disconnecting the aftermarket light bar and the non OEM fog lights. If that doesn’t work, we are going to try the two simple things suggested above in sequence. I’ve replaced the BCM and the Power steering module 2x.
If all of these doesn’t work, I’ll keep posted and praying an electrical “Yoda” from Mopar will surface who says “I can fix it”. The really really challenging thing for me is that I WAS a huge huge Jeep fan. Mopar has left me so far out in the cold, I honestly can’t come back. I still have hope I’ll get to the bottom of this but it’s been absolutely and completely without MOPAR help and thats tough.

 

[shotcoach]

Replace the green canbus block behind the glove box. $13 on ebay and 10 minutes to replace.

Is there a trick to removing the factory green canbus block? Probably a dumb question but I’m notorious for breaking things and don’t want to just pry something off. I thought I could just unbolt the black metal bracket (that the red arrows are pointing to in my pic) that the canbus blocks are connected to and get access to the little tabs on the bottom of the canbus block, but the bracket isn’t lifting off like I thought it would. Thanks in advance!

 

[Midwestjeepguy]

Is there a trick to removing the factory green canbus block? Probably a dumb question but I’m notorious for breaking things and don’t want to just pry something off. I thought I could just unbolt the black metal bracket (that the red arrows are pointing to in my pic) that the canbus blocks are connected to and get access to the little tabs on the bottom of the canbus block, but the bracket isn’t lifting off like I thought it would. Thanks in advance!

If memory serves me right, there's a bolt on the backside of the black metal bracket. Run your finger on the backside to feel for it. After all bolts were removed I had to wiggle mine pretty good to free it up, the black wiring harness held it in pretty tight. Pretty sure the harness is held in by 2 plastic push connectors as well. Loosen those to get the bracket completely free.

 

[gahammerle]

Is there a trick to removing the factory green canbus block? Probably a dumb question but I’m notorious for breaking things and don’t want to just pry something off. I thought I could just unbolt the black metal bracket (that the red arrows are pointing to in my pic) that the canbus blocks are connected to and get access to the little tabs on the bottom of the canbus block, but the bracket isn’t lifting off like I thought it would. Thanks in advance!

It slides out - left or right, I don't remember which. Look at the bottom side of the replacement and you'll see the 2 clips and be able to determine which way it slides out. No need to remove any bracket.

 

[azjl#3]

Oh for the ever loving F#%^ sakes, another thing I have to worry about with my 18.

I say best option in cases like this, unless the simple canbus swap fixes it, time to trade it in.

I had a 1 year old 1500 5.7, loved it, but one day it started knocking and stalling after start. A new EFI, stalling. Dealer, could not duplicate, traded next week for current 2018 JLUR. 5.7's are having issues... oiling problems with valve train.

Anone of of the OP or posters who have these gremlins, did any start with what happened last night while wifey was driving. Started slowing for a turn off hiway, turn signal on, then dash showed open door and door chime for about 10 seconds. Went away, has not returned. I'm just glad it didn't slam it into park doing 30 mph.

YGBFSM. Thought my 18 drama was over after a year getting steering to work right.

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