GPEC5 Blank ECU + VIN Programming - Where?

[bmpcamry09]

Sure would be nice to have the second PCM to swap out, lol. I'd love to get our '24 tuned, the transmission shifting drives me crazy, plus a little more HP would be nice for the 37's, lol.

Trans is separate with the TCM. It’s part of the valve body in the transmission.

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[ShadowCrawlers]

Trans is separate with the TCM. It’s part of the valve body in the transmission.

I know that it's separate from the ECM, just sayin that the stock transmission tune sucks.

 

[bmpcamry09]

I know that it's separate from the TCM, just sayin that the stock transmission tune sucks.

Well then hit me up no unlock needed for TCM. Just bypass cable, MPVI4, and 4 credits.

 

[Philosopheriam]

Folks,

I have a 2nd PCM for my Jeep - I had it unlocked by HPT and I am currently running a tune by bmpcamry09.

The process to obtaining a 2nd PCM went like this - full disclosure, my buddy is a Journeyman Chrysler mechanic working at a dealership
1. Order the PCM (relatively inexpensive, my cost around $125)
2. Show up at my buddy's house with breakfast
3. Remove the original PCM
4. Install the new PCM
5. Program the new PCM with the dealer Witech tool
6. Done

You can swap back and forth with the original/new PCMs and it is invisible to the vehicle.

Keep in mind that the programming process will install the latest calibration available from Chrysler.

Guys with a 6MT my run into an issue with a P0315 code that wont go away with a crank/cam relearn. The TLC relearn has to be completed which requires a specific, repeated process during a drive cycle.

 

[eastern]

Folks,

I have a 2nd PCM for my Jeep - I had it unlocked by HPT and I am currently running a tune by bmpcamry09.

The process to obtaining a 2nd PCM went like this - full disclosure, my buddy is a Journeyman Chrysler mechanic working at a dealership
1. Order the PCM (relatively inexpensive, my cost around $125)
2. Show up at my buddy's house with breakfast
3. Remove the original PCM
4. Install the new PCM
5. Program the new PCM with the dealer Witech tool
6. Done

You can swap back and forth with the original/new PCMs and it is invisible to the vehicle.

Keep in mind that the programming process will install the latest calibration available from Chrysler.

Guys with a 6MT my run into an issue with a P0315 code that wont go away with a crank/cam relearn. The TLC relearn has to be completed which requires a specific, repeated process during a drive cycle.

Wish we all had that Chrysler mech friend...
The programming portion is what has people uncertain.
I was on HPT website the other day, they state that they can do the programming, it is stated in 2nd bullet point of service notes on the bottom. I dont know the $, but if they can load the original factory tune and none of this post clutch issue updated glitched garbage, it may be a better way to go.

https://www.hptuners.com/product/dodge-pcm-service-gpec5/

 

[bmpcamry09]

Wish we all had that Chrysler mech friend...
The programming portion is what has people uncertain.
I was on HPT website the other day, they state that they can do the programming, it is stated in 2nd bullet point of service notes on the bottom. I dont know the $, but if they can load the original factory tune and none of this post clutch issue updated glitched garbage, it may be a better way to go.

https://www.hptuners.com/product/dodge-pcm-service-gpec5/

I've been meaning to make a post about this clutch stuff on the 6MT models since I have file variations of both pre and post clutch recalls and files from 2022 through 2026 and have compared them while tuning them, and a majority of those nannies implemented by Jeep are not actually created by the PCM tune, I think most of those nannies are within the BCM and EEPROM modules which are not controlled by HP Tuners. The main variations in the PCM are what DTC codes generated actually force a limp mode condition or not, but most of the torque related tables are the same with the exception of some driver demand/throttle tables.

I have found a few ways around the nannies to make these respond way better than factory without throwing the error, but it doesn't mean the error can't happen in the future as the clutch wears out more.

 

[Philosopheriam]

Wish we all had that Chrysler mech friend...
The programming portion is what has people uncertain.
I was on HPT website the other day, they state that they can do the programming, it is stated in 2nd bullet point of service notes on the bottom. I dont know the $, but if they can load the original factory tune and none of this post clutch issue updated glitched garbage, it may be a better way to go.

https://www.hptuners.com/product/dodge-pcm-service-gpec5/

They can't - ask them. As of my inquiry several weeks ago, they can't clone a GPEC5 or install a factory calibration.

Also, FYI, the latest calibration revision from Chrysler (which was installed on my 2nd PCM) was designed to reduce nuisance triggering of the clutch hot/service transmission warnings. I read the revision notes myself as displayed on my buddy's Witech tool.

 

[eastern]

They can't - ask them. As of my inquiry several weeks ago, they can't clone a GPEC5 or install a factory calibration.

Also, FYI, the latest calibration revision from Chrysler (which was installed on my 2nd PCM) was designed to reduce nuisance triggering of the clutch hot/service transmission warnings. I read the revision notes myself as displayed on my buddy's Witech tool.

Ughhhhh well there goes my hope... thank you for sharing.
REDUCE is the key word here, and it is as vague as it gets.

The update did "reduce" the nuisance for me, trasnlation:

• Did eliminate limp mode
• Replaced limp mode with slightly reduced engine performance
• "Hot clutch" message is gone, "service transmission" message remains
• "service transmission" message is accompanied by reduced engine perfomance
• Went from seeing "service transmission" every other stop light to once a week
• Pulled battery for several hours to replace spark plugs, "service transmission" occurrence is now back to every other stop light.

What is interesting, prolonged battery disconnect is what triggers worst symptoms on my Jeep. Seems like some temporary memory module resets in PCM during power down and goes haywire on reboot.

Hit 30000 miles on the odometer today, will begin search for a lemon law lawyer to get rid of this glitch on wheels.

 

[Philosopheriam]

Ughhhhh well there goes my hope... thank you for sharing.
REDUCE is the key word here, and it is as vague as it gets.

The update did "reduce" the nuisance for me, trasnlation:

• Did eliminate limp mode
• Replaced limp mode with slightly reduced engine performance
• "Hot clutch" message is gone, "service transmission" message remains
• "service transmission" message is accompanied by reduced engine perfomance
• Went from seeing "service transmission" every other stop light to once a week
• Pulled battery for several hours to replace spark plugs, "service transmission" occurrence is now back to every other stop light.

What is interesting, prolonged battery disconnect is what triggers worst symptoms on my Jeep. Seems like some temporary memory module resets in PCM during power down and goes haywire on reboot.

Hit 30000 miles on the odometer today, will begin search for a lemon law lawyer to get rid of this glitch on wheels.

Without hijacking this thread...

Do this and report back. I assume you have Jscan.

**PROCEDURE

- Get actual tire OD measurement.

1. Clear any codes

2. Verify your tire and gear settings
JSCAN > ADAPTATION > TIRES & AXLE SETTINGS > TIRE SIZE > set to ~35"

3. Use Jscan to reset the clutch EEPROM
via > adaptation -> vehicle maintenance -> PCM CLUTCH REPLACEMENT EEPROM RESET

4. Put the key out of range if the vehicle and let all of the modules go to sleep

5. Disconnect the all negative cables - let sit for 10-15 mins

6. Reconnect the negative cables

7. Perform the 6th gear relearn: (Vehicle speed must be between 40-80mph in top gear (6th) b. Accelerator pedal position must be greater than 0.392volts c. Flywheel torque > 75Nm. Once achieving the above conditions, it will take approximately 20 seconds to learn new top gear N/V ratio

***

With a properly functioning clutch, i.e one that isn't actually slipping, this procedure is how you get the clutch hot/service transmission warnings to go away.

Now, if you have a malfunctioning clutch or issues somewhere else, then it's a different story.

 

[eastern]

and a majority of those nannies implemented by Jeep are not actually created by the PCM tune, I think

most of those nannies are within the BCM and EEPROM modules which are not controlled by HP Tuners.

The main variations in the PCM are what DTC codes generated actually force a limp mode condition or not, but most of the torque related tables are the same with the exception of some driver demand/throttle tables.

I have found a few ways around the nannies to make these respond way better than factory without throwing the error, but it doesn't mean the error can't happen in the future as the clutch wears out more.

I mutilated your response a bit to help me understand better.
So it means that BCM/EEPROM is and has been acting up, but PCM was not programmed to react to it from the factory. The 19A update and onwards is what introduced and keeps that PCM - BCM/EEPROM correlation ?

To you last statement - I understand that tuning cant fix it, but can you identify and make it ignore those DTC codes that force PCM to respond to them? IF you cant disable it and they come back later, what is the threshold for triggering it?
I am asking because offroading with manual is nothing but clutch slippage, burning the clutch while going up the hill or loss of friction due to water/mud. If you cant eliminate the limp mode, id advise you not even mess with it, last thing someone needs is a false sense of hope while being on the edge of a cliff and this damn glitch on wheels goes into a limp

EDIT: forgot to ask:
In both instances of everything getting worse for my Jeep, i had battery disconnected for a prolonged period of time, which likely lead to PCM reset. Does that spark any ideas/assumptions to you, given what you know about how things work and all the nuisances?
Because, lets say you do apply some sort of "tuning" and it works... and then someone like me pulls his battery and resets his PCM, and on reboot that thing goes haywire again. See what i am saying?

 

[eastern]

Without hijacking this thread...

Do this and report back. I assume you have Jscan.

**PROCEDURE

- Get actual tire OD measurement.

1. Clear any codes

2. Verify your tire and gear settings
JSCAN > ADAPTATION > TIRES & AXLE SETTINGS > TIRE SIZE > set to ~35"

3. Use Jscan to reset the clutch EEPROM
via > adaptation -> vehicle maintenance -> PCM CLUTCH REPLACEMENT EEPROM RESET

4. Put the key out of range if the vehicle and let all of the modules go to sleep

5. Disconnect the all negative cables - let sit for 10-15 mins

6. Reconnect the negative cables

7. Perform the 6th gear relearn: (Vehicle speed must be between 40-80mph in top gear (6th) b. Accelerator pedal position must be greater than 0.392volts c. Flywheel torque > 75Nm. Once achieving the above conditions, it will take approximately 20 seconds to learn new top gear N/V ratio

***

With a properly functioning clutch, i.e one that isn't actually slipping, this procedure is how you get the clutch hot/service transmission warnings to go away.

Now, if you have a malfunctioning clutch or issues somewhere else, then it's a different story.

thank you, i have been lurking around for a while here and have done everything suggested, short of replacing Can Bus Star Connector somewhere behind glove box.

 

[bmpcamry09]

I mutilated your response a bit to help me understand better.
So it means that BCM/EEPROM is and has been acting up, but PCM was not programmed to react to it from the factory. The 19A update and onwards is what introduced and keeps that PCM - BCM/EEPROM correlation ?

To you last statement - I understand that tuning cant fix it, but can you identify and make it ignore those DTC codes that force PCM to respond to them? IF you cant disable it and they come back later, what is the threshold for triggering it?
I am asking because offroading with manual is nothing but clutch slippage, burning the clutch while going up the hill or loss of friction due to water/mud. If you cant eliminate the limp mode, id advise you not even mess with it, last thing someone needs is a false sense of hope while being on the edge of a cliff and this damn glitch on wheels goes into a limp

EDIT: forgot to ask:
In both instances of everything getting worse for my Jeep, i had battery disconnected for a prolonged period of time, which likely lead to PCM reset. Does that spark any ideas/assumptions to you, given what you know about how things work and all the nuisances?
Because, lets say you do apply some sort of "tuning" and it works... and then someone like me pulls his battery and resets his PCM, and on reboot that thing goes haywire again. See what i am saying?

I'm not exactly sure the direct relationship between them, but a common question I got when I started tuning was "can you make my tune how it was before the recall" and there is no way to directly do that as not all parameters regarding it are within the PCM side

DTCs can be disabled, but then again I haven't had any customers with those issues so I haven't dug into that too much. I just know that the post recall ones have dull throttle mapping compared to pre recall so that is one thing that gets changed first.

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