2021 JLUR (manual, 3.6L ESS) Won't Start

Spaffy

Well-Known Member
First Name
Art
Joined
Oct 27, 2020
Messages
203
Reaction score
562
Location
LA County, California
Vehicle(s)
'21 JL 2Dr Willys, '16 Ram 2500, '69 Dodge Polara

Speculating here; Perhaps the dealer tech went to that same connector you probed in your trials and saw it was molested. Looking at the wiring diagram, it is a three prong connector that is only utilizing two wires.

Maybe the tech saw it had been molested, noted a missing connection, and stopped there; without even looking at the wiring diagram to see there is no third wire.
Advertisement

 
OP
OP
demisx

demisx

Well-Known Member
First Name
Dee
Joined
Jul 9, 2020
Messages
254
Reaction score
179
Location
Desert Hot Springs, CA
Vehicle(s)
2021 JLU Rubicon 4-door (black)
Speculating here; Perhaps the dealer tech went to that same connector you probed in your trials and saw it was molested. Looking at the wiring diagram, it is a three prong connector that is only utilizing two wires.

Maybe the tech saw it had been molested, noted a missing connection, and stopped there; without even looking at the wiring diagram to see there is no third wire.
Good point. I thought that too, but that’s the clutch interlock switch in the picture I had probed, but the rep clearly referred to the 3-wire clutch pedal position sensor which is a different device sitting inside the cabin. I’ve specifically asked the service rep which one they were talking about and he said 3-wire pedal position sensor, not the interlock switch. Unless, there is a broken phone going “mechanic->service rep->me”.

I’ll try to find out more when I talk to them in person in the morning. Maybe have them identify the missing circuit on the JL Transmission wiring diagram I’d be bringing with me tomorrow.
 

NBB

Well-Known Member
Joined
Mar 10, 2019
Messages
144
Reaction score
143
Location
Boulder
Vehicle(s)
21 JLUR
Lol - let me grab my violin!

First - get that thing out of there. They are obviously incompetent, and there is no limit to the amount of short and long term financial, mechanical and electrical damage an incompetent mechanic can do.

Next - you were half done, I thought you would have finished! Get on TechAuthority and pay for the 3 day subscription. Follow the factory procedure for testing and swapping the clutch position sensor - as was indicated by the code.

EDIT - I was recently looking at specs for J-Scan. It appears to give data stream for all modules. Go get that as well, or something equivalent. You want to see what the computer sees for the sensors.
 
OP
OP
demisx

demisx

Well-Known Member
First Name
Dee
Joined
Jul 9, 2020
Messages
254
Reaction score
179
Location
Desert Hot Springs, CA
Vehicle(s)
2021 JLU Rubicon 4-door (black)
Lol - let me grab my violin!

First - get that thing out of there. They are obviously incompetent, and there is no limit to the amount of short and long term financial, mechanical and electrical damage an incompetent mechanic can do.

Next - you were half done, I thought you would have finished! Get on TechAuthority and pay for the 3 day subscription. Follow the factory procedure for testing and swapping the clutch position sensor - as was indicated by the code.
Thank you, sir. You one of the few who makes the most sense to me.

Do you think TechAuthority will have 2021 materials? When I look at their "Service manuals" section, the latest listed is 2020. Perhaps most of it still applies or will online subscription give me access to 2021? Sorry, never used this site before.

EDIT - I was recently looking at specs for J-Scan. It appears to give data stream for all modules. Go get that as well, or something equivalent. You want to see what the computer sees for the sensors.
I remember there was "Freeze Frames" section that sometimes will be blank and sometime will show some values. I'll look into it more tomorrow once I get the Jeep back in the garage.

Screen Shot 2021-03-01 at 8.00.06 PM.png
 

NBB

Well-Known Member
Joined
Mar 10, 2019
Messages
144
Reaction score
143
Location
Boulder
Vehicle(s)
21 JLUR
You're looking to see if they sell USB repair manuals. They don't - and who cares because my experience is that they are incomplete and suck very badly - you'd be back on TechAuthority anyway for a real-world repair. You need to pay for TechAuthority. It is dealer level info. You will do no better. I have not subscribed recently, but I have in the past.

https://www.techauthority.com/en-us/products/TAUSER03DAY

Demonstrate some of the attention to detail you've displayed above and read the information that the flunky tech at the dealer couldn't be bothered to and I think you will do better with this than claiming a wiring harness has gone missing! Subscribe on Th Eve/Friday so you have the full wknd - or pay for it twice to get your ducks in a row and learn a lot in the process.
 
OP
OP
demisx

demisx

Well-Known Member
First Name
Dee
Joined
Jul 9, 2020
Messages
254
Reaction score
179
Location
Desert Hot Springs, CA
Vehicle(s)
2021 JLU Rubicon 4-door (black)
You're looking to see if they sell USB repair manuals. They don't - and who cares because my experience is that they are incomplete and suck very badly - you'd be back on TechAuthority anyway for a real-world repair. You need to pay for TechAuthority. It is dealer level info. You will do no better. I have not subscribed recently, but I have in the past.

https://www.techauthority.com/en-us/products/TAUSER03DAY

Demonstrate some of the attention to detail you've displayed above and read the information that the flunky tech at the dealer couldn't be bothered to and I think you will do better with this than claiming a wiring harness has gone missing! Subscribe on Th Eve/Friday so you have the full wknd - or pay for it twice to get your ducks in a row and learn a lot in the process.
Understood. Will do that! By the way, I've tried their online demo section and the site throws 'Not Found" error left and right once I've selected my vehicle and the engine type. I've also tried it with the Internet Explorer they require (who the hell still does this in 2021???) - the same thing. I hope their paid section works better than this. 🤞🙂

Screen Shot 2021-03-01 at 8.23.02 PM.png
 

NBB

Well-Known Member
Joined
Mar 10, 2019
Messages
144
Reaction score
143
Location
Boulder
Vehicle(s)
21 JLUR
That site is used 24-7 all over the planet. Looks like they have a crude "block" in place for the demo - no big deal, IMO.

EDIT - you might also try calling https://www.aetools.us/. They are a value add reseller that offers support. Same prices. ie, if you have problems, you might be able to get someone on the phone faster than if you went straight through TechAuthority. I have never tried it myself, maybe someone else here has, but you might consider it or at least call them first so you know what they offer - for reference. I think a lot of guys trying more complicated procedures such as module flashing use aetools specifically so they can get someone to talk them through the tools and software.
 
OP
OP
demisx

demisx

Well-Known Member
First Name
Dee
Joined
Jul 9, 2020
Messages
254
Reaction score
179
Location
Desert Hot Springs, CA
Vehicle(s)
2021 JLU Rubicon 4-door (black)
That site is used 24-7 all over the planet. Looks like they have a crude "block" in place for the demo - no big deal, IMO.

EDIT - you might also try calling https://www.aetools.us/. They are a value add reseller that offers support. Same prices. ie, if you have problems, you might be able to get someone on the phone faster than if you went straight through TechAuthority. I have never tried it myself, maybe someone else here has, but you might consider it or at least call them first so you know what they offer - for reference. I think a lot of guys trying more complicated procedures such as module flashing use aetools specifically so they can get someone to talk them through the tools and software.
This is great to know. Thank you. Let the new days of fun begin!
 
OP
OP
demisx

demisx

Well-Known Member
First Name
Dee
Joined
Jul 9, 2020
Messages
254
Reaction score
179
Location
Desert Hot Springs, CA
Vehicle(s)
2021 JLU Rubicon 4-door (black)
Speculating here; Perhaps the dealer tech went to that same connector you probed in your trials and saw it was molested. Looking at the wiring diagram, it is a three prong connector that is only utilizing two wires.

Maybe the tech saw it had been molested, noted a missing connection, and stopped there; without even looking at the wiring diagram to see there is no third wire.
I think you were spot on @Spaffy. I've asked my service rep yesterday morning again to make some pictures of everything the mechanic thought was "re-wired" along with the description, so I can forward it to Jeep Cares, because I was 99.9% sure none of this happened and it was some kind of misunderstanding. I've once again confirmed with the rep that the mechanic was referring to the 3-wire clutch pedal sensor and not the 2-wire interlock switch I've previously probed. The rep said he had to run this by his foreman, but I could tell they were reluctant to make any pics.

An hour later, his foreman calls me and asks similar questions about the Jeep (i.e. when was purchased, how many miles it had, was it ever in the service before, who did the mods etc.). Basically, trying to find out if there is anyone he could pin this issue on. During the conversation, he tells me that the clutch switch is missing an entire wire. This rings a warning bell. Sure enough, he's referring to the 2-wire interlock switch thinking that the 3-rd prong connector is missing one wire circuit. Which tells me that either they didn't even bother to check the diagram or they don't know how to read it. I think they saw my dried up liquid electrical tape that I've touched the holes left by the needles and they immediately came to a conclusion that switch was rewired. Not even checking the diagram and checking whether this switch was working or not. That took them 2 days.

After my explanation of the difference between the interlock switch and the clutch pedal position sensor, the foreman promises to take a look at the problem personally and give me an update. Later that day, my service rep calls and apologizes saying that the mechanic had wrong diagrams or something like that and he was looking at the wrong thing. Now, he thinks the issue is the PCM board and a the order for a new board has been placed. Once it arrives, hopefully today, they are going to replace what's in the Jeep and flush it. They hope this will fix the problem. Me - not so much for some reason. But I hope I am wrong this time.

The saga continues... 😃
 

NBB

Well-Known Member
Joined
Mar 10, 2019
Messages
144
Reaction score
143
Location
Boulder
Vehicle(s)
21 JLUR
Stay on them and let us all know if replacing the PCM actually fixes anything. I'm not seeing it, especially if a trouble code points to a port to a sensor that is difficult to access. At least you got them to do their screwing around on warranty hours, though I don't think the factory pays for electrical diagnostic time. Lol - why most PCM's really get replaced - more billable.

For the needle holes in a wire, just rub the hole with your fingers, it will usually close up on its own and become invisible, especially with the tiny needles you were using. My test leads use a bunch of pins. Usually a few minutes later I can't see any holes.

IMG-3217.jpg
 
OP
OP
demisx

demisx

Well-Known Member
First Name
Dee
Joined
Jul 9, 2020
Messages
254
Reaction score
179
Location
Desert Hot Springs, CA
Vehicle(s)
2021 JLU Rubicon 4-door (black)
Stay on them and let us all know if replacing the PCM actually fixes anything. I'm not seeing it, especially if a trouble code points to a port to a sensor that is difficult to access. At least you got them to do their screwing around on warranty hours, though I don't think the factory pays for electrical diagnostic time. Lol - why most PCM's really get replace - more billable.
Will do. If it was me, I think I would disconnect the 3-wire connector from the current clutch pedal position sensor and plug a new one in just to rule out a bad sensor fault before replacing an expensive PCM board, but who knows. Maybe they have a good reason to go straight to PCM.

For the needle holes in a wire, just rub the hole with your fingers, it will usually close up on its own and become invisible, especially with the tiny needles you were using. My test leads use a bunch of pins. Usually a few minutes later I can't see any holes.

IMG-3217.jpg
Thank you for the tip! I'll try this next time. What kind of tool is this in the picture? Can you please share a name or a link. I'd like to learn more about it.
 

NBB

Well-Known Member
Joined
Mar 10, 2019
Messages
144
Reaction score
143
Location
Boulder
Vehicle(s)
21 JLUR
Mine aren't sold anymore, but I believe they would be very similar to "OTC 3906" - from OTC Tools. They should plug right into your Fluke.

EDIT - the reason they didn't go for the sensor is because it's apparently difficult to access and they wouldn't get paid as much money. They still may actually do that and say otherwise.
 
OP
OP
demisx

demisx

Well-Known Member
First Name
Dee
Joined
Jul 9, 2020
Messages
254
Reaction score
179
Location
Desert Hot Springs, CA
Vehicle(s)
2021 JLU Rubicon 4-door (black)
Well. Just heard from the dealership. They've installed the new PCM, flushed it and ... The problem is still there. What a shocker! 🙄

The mechanic thinks now the issue maybe somewhere at the connector or the harness level. He'll be checking it our tomorrow. If he cannot find the problem, the next step, according to the rep, would be to open a new case with FCA. Sounds like I'll be without my wheels for a while.
 

NBB

Well-Known Member
Joined
Mar 10, 2019
Messages
144
Reaction score
143
Location
Boulder
Vehicle(s)
21 JLUR
Lol. There are 4 connectors involved according to the wiring diagram. Problems like this are generally found at a connector, and you've gotten to see already how good this guy is with connectors.
 
OP
OP
demisx

demisx

Well-Known Member
First Name
Dee
Joined
Jul 9, 2020
Messages
254
Reaction score
179
Location
Desert Hot Springs, CA
Vehicle(s)
2021 JLU Rubicon 4-door (black)
Got a call yesterday from the dealership. They said there was a broken wire in the harness and they fixed it. I picked it up and, indeed, the Jeep started without any issues. Drove off of the parking lot and... the check engine light (CEL) came on.

Got home without any mechanical issues. Decided to see what exactly was done. Besides a couple ripped off harness clips (apparently, the service never heard of the molding remove pry tool), I see that they've cut off the yellow sensor signal wire in the main harness and ran a new black wire from another harness in the passenger well all the way to the PCM. I'm not sure if this is an accepted way to fix it, but I'd rather see a new harness installed instead what seems like a bandaid. And, of course, only visible portion of the new wire was put in a loom. The rest runs as-is.

I've cleared all engine DTC codes last night and the CEL went off. I drove it around this morning and again no mechanical issues. But, the CEL came on again after about 30 mins of driving. The new code is P057B (brake pedal position sensor "a" circuit performance). I don't know yet if this is something was introduced by the "fix" or it wasn't showing up earlier because the P0808 was firing. Will be researching.

IMG_2151.jpg


IMG_2156.jpg


Screen Shot 2021-03-05 at 10.21.29 AM.png


IMG_2163.PNG
 
Advertisement

Quake LED
 
Advertisement
Top