HELP,,, Jeep won’t start :(

WranglerMan

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Working on these newer vehicles with all the technology built into them is a double edged sword, i remember the days I had my manual tranny CJ5 ragtop…..cold as hell in the winter when I lived in the Midwest but the engine was super simp to work on and then I had an International Scout II that was pretty easy to work on …

Back in those days there was no computers, BT stereos etc.....
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Mike921921

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Working on these newer vehicles with all the technology built into them is a double edged sword, i remember the days I had my manual tranny CJ5 ragtop…..cold as hell in the winter when I lived in the Midwest but the engine was super simp to work on and then I had an International Scout II that was pretty easy to work on …

Back in those days there was no computers, BT stereos etc.....
Yeah, now we have Auto Park and ESS - woo hoo!
 

WranglerMan

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Yeah, now we have Auto Park and ESS - woo hoo!
Auto Park can be fixed with a seat belt extender and ESS with a Tazer or JSCAN but as we all know this is just the tip of technology
 

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Too long, didn't read everything ... but here's a Cole's Notes version of what likely happened;
Somewhere under the dash there was a wiring harness that was pinched. When you were installing your radio you un-pinched that harness and inadvertently broke or shorted a wire or two, hence the subsequent cooking class vis-a-vis the PCM/ECM.
Or, alternatively, when installing your radio, you pinched a wiring harness under there causing it to break a wire or two and fry the PCM/ECM.
Either way, there is no way you would have known until the PCM/ECM toasted.
Since the shop probably could not decipher which way it happened, you ended up with the bill or the job.
Could be that the shop is still going to submit the case for warranty or policy consideration, and if they get some money, refund all or part of your bill commensurate with what they get from FCA. Personally, I would be inclined to ask that question before anything.
As for the wires that you put in ... they would have no idea where you wanted them so they left them for you to put away. Can't really fault them for that.
All in all, under a thousand bucks for an undetermined wiring issue is not a bad deal on new computerized vehicle.
 

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Auto Park can be fixed with a seat belt extender and ESS with a Tazer or JSCAN but as we all know this is just the tip of technology
I have a seat belt extender in situ to disable Auto Park (having that feature stop me cold once was more than enough), and the Auto Stop Eliminator harness plugged in to maintain the Off setting.

This was money that shouldn't have needed to be spent, but there for the grace of technology go We.
 

WranglerMan

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I have a seat belt extender in situ to disable Auto Park (having that feature stop me cold once was more than enough), and the Auto Stop Eliminator harness plugged in to maintain the Off setting.

This was money that shouldn't have needed to be spent, but there for the grace of technology go We.
I’m sure we can all agree that things like auto park, ESS and a few other things should have never been incorporated into the Wrangler
 
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kapk22

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Too long, didn't read everything ... but here's a Cole's Notes version of what likely happened;
Somewhere under the dash there was a wiring harness that was pinched. When you were installing your radio you un-pinched that harness and inadvertently broke or shorted a wire or two, hence the subsequent cooking class vis-a-vis the PCM/ECM.
Or, alternatively, when installing your radio, you pinched a wiring harness under there causing it to break a wire or two and fry the PCM/ECM.
Either way, there is no way you would have known until the PCM/ECM toasted.
Since the shop probably could not decipher which way it happened, you ended up with the bill or the job.
Could be that the shop is still going to submit the case for warranty or policy consideration, and if they get some money, refund all or part of your bill commensurate with what they get from FCA. Personally, I would be inclined to ask that question before anything.
As for the wires that you put in ... they would have no idea where you wanted them so they left them for you to put away. Can't really fault them for that.
All in all, under a thousand bucks for an undetermined wiring issue is not a bad deal on new computerized vehicle.
I’ve read the notes on the receipt a few times and concluded they found a pinched wire under the drivers seat. By the looks of the area when I got the Jeep back, it does appear they worked on that area. They did not snap the side floor panel back in all the way and one of the main wires I ran was pulled up and out of the carpet.

I would have to respectfully disagree about the way they left the wires. I spent a lot of time upside down, crammed up under the dash to run those wires with zip ties and some sheathing. In order to run some of them up to the head unit, I had to use a dash snake.

I understand they had to trouble shoot at first. However, all they would have needed to do is bundle those up a little and zip tied them out of the way. At least it would have been safe to drive. And,,,; they did end up having my floor mat after all.

I am grateful I have my Jeep back, don’t get me wrong. But this was not the kind of service I expected from a dealership of their size.
 

WranglerMan

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@kapk22 i am truly sympathetic to your bad experience at the Dealer Service Ctr. you are correct they should and could have done a better job making things tidy but they chose not to and thats the biggest downfall of a lot of Service Centers nowadays and thats truly a shame.

I wish you and others that have had bad experiences a more positive future with your Jeeps, it seems we don’t hear much of the positive but I honestly believe if they slowed down and did a more professional job we would all be better off.
 

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I’m sure we can all agree that things like auto park, ESS and a few other things should have never been incorporated into the Wrangler
I know of at least one family that would disagree. Anton Yelchin.
Personally, I keep my seat belt on and if for some reason I can't, I would just buckle it behind me.
And the Start/Stop doesn't bother me in the least. It's been on last 3 vehicles.
 

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As a previous avionics technician, I would be very curious as to exactly where the pinch was and specifically how they repaired it. (Thinking long-term reliability, etc...)
 

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They absolutely are different.
The PCM is a Powertrain Control Module, and it manages everything.
The ECM is the Engine Control Module, and it only manages the engine.
The TCM is the Transmission Control Module, and it only manages the transmission.

In the world I work in, class 8 heavy duty trucks, we have all of the above, plus several others. In today's trucks, depending on the brand you buy, it takes about 22 computers to run one.

Back in the old mechanical days you would put your foot down on the accelerator pedal and it would push a rod that would adjust the carburator and you would begin to move, speed, up, slow down, whatever action you wanted.
Today, you put your foot down on the accelerator pedal, and it moves a potentiometer, which tells the transmission (automatic or manual, just different languages) what you want. The transmission asks the engine for the power, and tells the rear end(s) what's coming. The rear end(s) check with the ABS system to confirm traction state, and prepares to receive the power. If the rear ends don't like what's coming it,/they tell the transmission, and the transmission readjusts its request of the engine ... and so on, and so on ... until all the pieces are happy. Millions upon millions of communications per millisecond.
The PCM, which manages this entire system, doesn't really care though if you, the driver, are happy or not.
Michael,

Not to disagree with your post but I'd like to add some clarity. I was a Powertrain Software Engineer for Chrysler for almost two decades before leaving the automotive industry for other software development opportunities.

Many (lower cost) vehicles have essentially just one main control computer. This is typically called the 'Powertrain Control Module' or PCM. It manages all facets of that vehicle's electronics.

For more expensive automotive applications a dedicated controller is implemented for generally each of the following subsystems:
- Engine Control Module (ECM)
- Transmission Control Module (TCM)
- Body Control Module (BCM)
- Electronic Vehicle Information Center (EVIC)

Of course some vehicles may implement any combination of these controllers. However, this terminology holds for just about all major automotive manufacturers and suppliers.

The most significant clarification I'd like to highlight is that some components and features are either 'predictive' or 'reactive'. Most everything behind the predictive engine management functionality are purely reactive in nature. This includes just about everything outside the engine controller itself.

Typically, the ECM collects information from these modules and various sensors, such as upstream, downstream O2, Manifold Air Pressure (MAP), Intelligent Battery Sensor (IBS), Accelerator Input Potentiometer as well as other I/O devices scattered throughout the entire vehicle. It's primary purpose is to predict all the necessary power and torque requirements given driver and vehicle input. Then deliver the necessary power to satisfy all of this informational input.

The TCM provides real-time data in regards to both the input/output shaft speeds as well as grade calculation and gear selection based on current torque and momentum conditions. The transmission controller is primarily responsible for selecting an appropriate gear based on the amount of torque being supplied. Of course, this is the most 'collaborative' component that exchanges full duplex data both ways with the ECM. However, the majority of data provided back to the Engine Controller is still 'reactive' in nature. The transmission basically accepts whatever power the engine gives it until it can't, then it starts complaining. Furthermore, with all the confidence that the ECM has been programmed to know where the trans and powertrain limits exist before-hand. The transmission control algorithms are designed with the assumption that the engine controller will not intentionally try to destroy it (or anything else).

The BCM provides practically all safety related input such as door, alarm, seat belt, air-bag, brake and collision sensor status. It also is responsible for all HVAC, turn/brake signal, headlamp and radio power control.

Most all communication within the vehicle over the internal Controller Area Network (CAN) bus is one-way in nature. Almost everything flows into the ECM (or PCM). This includes all transfer case and axle operations. In fact nearly 50% of all engine controller software feature set responsibility implemented was to ensure that any instantaneously applied torque could not damage any of the transmission, drive-shaft, transfer-case, axle or differential components. Torque had to be carefully provided in specific values per unit time in order to protect from breaking anything due to over-torque speed (1st), acceleration (2nd) and jerk (3rd derivative)conditions in real-time. Torque calibrations are, and will continue to be, the most important functions of any vehicle offering in any Model Year release.

Lastly, most communication bandwidth occurs within hundreds of milliseconds; only about a dozen messages per second (not many millions). The CAN bus protocol is limited to only about 50 to 125 kilobits/s, or thousands of bits, per second. A typical CAN message can easily contain several thousands of bits of information per message. In fact the payload portion of a CAN message is only seven (7) bytes or 56 bits in length. So a lot of addressing and overhead header data for a small amount of real message context.

The vehicle is certainly not a super-computer. It reacts to information in typical CAN message packets in the span of about a tenth of a second intervals (averaging about a 100 millisecond rates). Some high priority messages a little quicker but most a whole lot slower.

Once you have a basic understanding of what information is required, it's pretty easy to visualize how these components and sensors 'talk' to these various controllers.

Of course the really high-speed (high-bandwidth) control, such as spark and fuel injector timing, these are typically implemented with interrupts on the ECM/PCM CPU architecture directly. Only request, status or metric info relating to these functions tend to travel over the CAN bus.

While those with engineering or technical degrees are able to easily understand the sophistication within the modern car, anyone with any technical aptitude should be able to visualize the basic concepts. The only reason that the modern electronics is so complicated is due to the legal and natural requirement to safeguard these vital controls from tampering. Therefore the ability to plug into and monitor and/or modify this information is obfuscated and cryptographically encoded for very needed reasons.

Hope this helps with everyone's basic-level understanding.

Lastly, I feel for the OP's struggles. Each and every third-party provider is trying their very best to eak out a meager livelihood by providing products and services much better than what the factory is willing to provide. And doing so within what is a very challenging environment indeed. The manufacturer's must protect it's servicing channels while minimizing it's warranty liability. All the while these 3rd-party entrepreneurs must tap into and reverse engineer, clearly taking many chances to implement their genius where nearly anything (at all) can go wrong. And sometimes very wrong such as a dead vehicle.

I really feel for Kasey's (@kapk22) troubles. Trying to play within this environment without a comprehensive cook-book 'how-to' guide is most unfortunate. However, the 3rd-party suppliers can only realistically provide a 'happy-path' best case set of instruction set with the lowest common-denominator type of vehicle set-up. Trying to predict all the various dynamic differences, along with the plethora of things that can go wrong is more than daunting, it's downright nearly impossible. Even the very best educated, highly-trained professional installers would have the same difficulties.

My hats off to you Kasey for sharing your experience. I'm certain everyone on this thread has gained from your experience.

Thanks for staying positive, and best wishes that your JL becomes the best one on the planet. At least for you. If you had a go-fund-me page I'd contribute. Just because of your upbeat attitude and enthusiasm, clearly helping the rest of us.

Maybe not exactly a job well done, but kudos for the persistence and absolute willingness to see it through.

Thanks a bunch.
Jay
 

Yogi

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Thank you Jay for that comprehensive explanation. The Daimler folks that explained it to me weren't nearly as far up the technology food chain as you :)
Please don't ever think that I take correction or clarification as an insult. I relish the opportunity to learn, especially from those who relish the value of teaching.
The CANbus is only 50 to 125 kilobits/second???
That certainly explains a lot of things that we struggle with vis-a-vis heavy trucks where the biggest issue is short cycling the starting process. If a driver doesn't wait long enough we get Virtual Tech messages out the wahzoo until he shuts it off and does it again ... properly this time ... LOL
Thanks again for taking the time to write that piece.

Michael.
 
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kapk22

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Michael,

Not to disagree with your post but I'd like to add some clarity. I was a Powertrain Software Engineer for Chrysler for almost two decades before leaving the automotive industry for other software development opportunities.

Many (lower cost) vehicles have essentially just one main control computer. This is typically called the 'Powertrain Control Module' or PCM. It manages all facets of that vehicle's electronics.

For more expensive automotive applications a dedicated controller is implemented for generally each of the following subsystems:
- Engine Control Module (ECM)
- Transmission Control Module (TCM)
- Body Control Module (BCM)
- Electronic Vehicle Information Center (EVIC)

Of course some vehicles may implement any combination of these controllers. However, this terminology holds for just about all major automotive manufacturers and suppliers.

The most significant clarification I'd like to highlight is that some components and features are either 'predictive' or 'reactive'. Most everything behind the predictive engine management functionality are purely reactive in nature. This includes just about everything outside the engine controller itself.

Typically, the ECM collects information from these modules and various sensors, such as upstream, downstream O2, Manifold Air Pressure (MAP), Intelligent Battery Sensor (IBS), Accelerator Input Potentiometer as well as other I/O devices scattered throughout the entire vehicle. It's primary purpose is to predict all the necessary power and torque requirements given driver and vehicle input. Then deliver the necessary power to satisfy all of this informational input.

The TCM provides real-time data in regards to both the input/output shaft speeds as well as grade calculation and gear selection based on current torque and momentum conditions. The transmission controller is primarily responsible for selecting an appropriate gear based on the amount of torque being supplied. Of course, this is the most 'collaborative' component that exchanges full duplex data both ways with the ECM. However, the majority of data provided back to the Engine Controller is still 'reactive' in nature. The transmission basically accepts whatever power the engine gives it until it can't, then it starts complaining. Furthermore, with all the confidence that the ECM has been programmed to know where the trans and powertrain limits exist before-hand. The transmission control algorithms are designed with the assumption that the engine controller will not intentionally try to destroy it (or anything else).

The BCM provides practically all safety related input such as door, alarm, seat belt, air-bag, brake and collision sensor status. It also is responsible for all HVAC, turn/brake signal, headlamp and radio power control.

Most all communication within the vehicle over the internal Controller Area Network (CAN) bus is one-way in nature. Almost everything flows into the ECM (or PCM). This includes all transfer case and axle operations. In fact nearly 50% of all engine controller software feature set responsibility implemented was to ensure that any instantaneously applied torque could not damage any of the transmission, drive-shaft, transfer-case, axle or differential components. Torque had to be carefully provided in specific values per unit time in order to protect from breaking anything due to over-torque speed (1st), acceleration (2nd) and jerk (3rd derivative)conditions in real-time. Torque calibrations are, and will continue to be, the most important functions of any vehicle offering in any Model Year release.

Lastly, most communication bandwidth occurs within hundreds of milliseconds; only about a dozen messages per second (not many millions). The CAN bus protocol is limited to only about 50 to 125 kilobits/s, or thousands of bits, per second. A typical CAN message can easily contain several thousands of bits of information per message. In fact the payload portion of a CAN message is only seven (7) bytes or 56 bits in length. So a lot of addressing and overhead header data for a small amount of real message context.

The vehicle is certainly not a super-computer. It reacts to information in typical CAN message packets in the span of about a tenth of a second intervals (averaging about a 100 millisecond rates). Some high priority messages a little quicker but most a whole lot slower.

Once you have a basic understanding of what information is required, it's pretty easy to visualize how these components and sensors 'talk' to these various controllers.

Of course the really high-speed (high-bandwidth) control, such as spark and fuel injector timing, these are typically implemented with interrupts on the ECM/PCM CPU architecture directly. Only request, status or metric info relating to these functions tend to travel over the CAN bus.

While those with engineering or technical degrees are able to easily understand the sophistication within the modern car, anyone with any technical aptitude should be able to visualize the basic concepts. The only reason that the modern electronics is so complicated is due to the legal and natural requirement to safeguard these vital controls from tampering. Therefore the ability to plug into and monitor and/or modify this information is obfuscated and cryptographically encoded for very needed reasons.

Hope this helps with everyone's basic-level understanding.

Lastly, I feel for the OP's struggles. Each and every third-party provider is trying their very best to eak out a meager livelihood by providing products and services much better than what the factory is willing to provide. And doing so within what is a very challenging environment indeed. The manufacturer's must protect it's servicing channels while minimizing it's warranty liability. All the while these 3rd-party entrepreneurs must tap into and reverse engineer, clearly taking many chances to implement their genius where nearly anything (at all) can go wrong. And sometimes very wrong such as a dead vehicle.

I really feel for Kasey's (@kapk22) troubles. Trying to play within this environment without a comprehensive cook-book 'how-to' guide is most unfortunate. However, the 3rd-party suppliers can only realistically provide a 'happy-path' best case set of instruction set with the lowest common-denominator type of vehicle set-up. Trying to predict all the various dynamic differences, along with the plethora of things that can go wrong is more than daunting, it's downright nearly impossible. Even the very best educated, highly-trained professional installers would have the same difficulties.

My hats off to you Kasey for sharing your experience. I'm certain everyone on this thread has gained from your experience.

Thanks for staying positive, and best wishes that your JL becomes the best one on the planet. At least for you. If you had a go-fund-me page I'd contribute. Just because of your upbeat attitude and enthusiasm, clearly helping the rest of us.

Maybe not exactly a job well done, but kudos for the persistence and absolute willingness to see it through.

Thanks a bunch.
Jay

Jay,

Thank you for taking the time to reply with such depth and explanation. I really appreciate it and am certain others do as well.

The Jeep is running good for now, aside from the knocking up front. I will continue searching for the cause this week. If I cannot track it down, I will take her back to the dealership and request they find and fix it. I also don’t feel 100% confidant with the advisors answer to my question before diving back into the instal myself. If this was a “pinched wire” I need to know exactly which one. Or, at the least, which harness/plug it happened in.

As far as the condition the Jeep was in when I picked her up, (wires and missing floor mat) I plan on following up with FCA and the general manager at the dealership. Likely after I get the knocking figured out. I will definitely keep this thread updated.
 

WranglerMan

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@kapk22 you have been a pretty solid Trooper thru all of this, you must have a lot of patience….
 
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kapk22

kapk22

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@kapk22 you have been a pretty solid Trooper thru all of this, you must have a lot of patience….
Thank You Sir!!

I have been trying my hardest to stay positive and not feel like a jackass during this.
 
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