How to Install a Used PCM (GPEC2/GPEC2A) Without the Original PCM and Fix Error P0513

How to Install a Used PCM (GPEC2/GPEC2A) Without the Original Module

After moving to the USA from Ukraine in 2019, I have been working as a truck driver in Cleveland, Ohio. Before that, I worked in automotive electronics for 20 years.

A mechanic in our company bought a 2018 Dodge Charger with a 6.4L engine, but its PCM (GPEC2A) was stolen. He purchased a used PCM, but installing it in the car turned out to be a major problem!

What’s the Issue?

There is no clear information on how to synchronize a used PCM with the immobilizer (RFHUB/BCM). Even expensive tools like Autel IM608 do not support this function. The ECUHERO software can clone these PCMs but does not allow installing a used one without the original.

The mechanic sent the PCM twice to a specialized company that handles these issues, but they were unsuccessful.

My Solution

I decided to investigate where the synchronization bytes between the PCM, BCM, and RFHUB are stored, and it turned out to be quite simple.

I contacted the support teams of several programming tool manufacturers to request this function (installing a used PCM without the original), but they did not respond. It is surprising that even high-end tools cannot perform such a simple operation.

For example, OBDSTAR DC706 can clone RFHUB but does not allow installing a used PCM. However, all that is needed is to read 6 bytes and write them into the PCM in Bench Mode!

How to Install a Used PCM GPEC2/GPEC2A

If you own a Dodge Charger, Challenger, RAM, or another vehicle with GPEC2/GPEC2A, and you need to replace the PCM ? give this information to a specialist who works with processor programmers.

Steps to Follow:

1. Read EEPROM 95640 from GPEC2A.
2. Read the microcontroller MC9S12XEG384 in RFHUB or SPC5606 in BCM.
3. Find the 6 bytes in the RFHUB module and write them into the PCM.
4. Optionally, write the VIN (it repeats three times).

�� If you are working with BCM, the 6 bytes are stored in a mirrored layout.

What’s in the Archive?

I have prepared an archive that contains:
✅ Three files with the necessary 6 bytes (the filenames will indicate the address and synchronization bytes).
✅ Three images showing where these bytes are located.

https://dropmefiles.com/BMVcJ
�� Archive password: 123
�� Archive password: city_Boryslav

This method allows you to quickly install a used PCM without needing the original. I am sharing this solution to help both specialists and car owners who face this problem.

If you have any questions or need more details ? feel free to ask!

great info. what is used to read bcm+rfhub on bench? cda6 or obdstar? would this also work if replacing bcm or rfhub if you copy these bytes to a used bcm/rfh?

No, not bench. I don't have OBD STAR; it reads these modules in bench mode. I used the Xprog M programmer to read the BCM and RHFUB. Yes, that's correct?to replace the BCM and RHFUB, I think these 5 bytes should be enough.

Quote:

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Originally Posted by roman123

No, not bench. I don't have OBD STAR; it reads these modules in bench mode. I used the Xprog M programmer to read the BCM and RHFUB. Yes, that's correct?to replace the BCM and RHFUB, I think these 5 bytes should be enough.

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But to install the PCM, you only need to read the RHFUB to retrieve the secret 6 bytes.

Obd star is stupid expensive. It's like insanely expensive. You could go the next step down would be getting a vvdi prog and that would do it but they're like $400.. You don't necessarily need to marry the PCM like that. The proper way to do it would be to virginize The PCM and then have it pull that data from the body control module which there is a PCM replacement option in alpha OBD. If I'm not mistaken and you could do it all through the OBD2 port. The PCMS don't have any sort of lock like the RF hubs do if they've been updated or if they're like 2020 and up. I program Hellcat conversions all the time. I can program body control modules and everything almost completely through alpha OBD and it doesn't matter what year it is. Anybody that says you cannot write the BCM because it's locked or whatever or it's a one-time right? Only. Just look up the definition of what an eeprom is... It's right in the name it's electronically erasable which means it can be rewritten. If it can be locked or written by software. It can be unlocked and rewritten by software. That's all there is to it. I've done I think to date 23 Hellcat conversions of all different types. Anything from 2021 red eye swap into a 2015 Hellcat Challenger to a 2019 Hellcat conversion like the whole thing every last module. Every last little detail of it swapped into the 2014 300S. And all of it could be done but to do it the way that I do it in less than an hour. Those are all well. You know trade secrets... But it is all something that can be done. I mean hell. If you're in California I'll do it for you. Haha or I'll mail you the stuff. Pre-programmed. But as far as the PCM is concerned, you can use something like ECU hero or aemt Max and you can write like a blank eepron to it. That's still programmable and viable cuz it leaves the calibration data alone but the eeprom data will stay blank and virgin so that you'll be able to go in there and just do a PCM replacement and it'll automatically copy that stuff because all that stuff takes it from the network itself. So the body control module the ABS the RF hub. They have backups of all the other modules around them. So like when you go to replace the body control module not in a swap. But let's say you're just replacing a bad body control module. It's as easy as popping in a brand new body control module, turning the key on for 10 seconds. I usually wait 15 and turn the key off, pulling it out, locking the door and then waiting a couple minutes. Get back in. Everything is copied over. It's done completely automatically because it pulls that data from the RF hub and the ABS. A lot of people don't know that or are are completely unaware of how these networks work, but I spent the last couple years like obsessed with them and spending hundreds and hundreds of hours and I don't know how many thousands of dollars and trial and error. I mean you name it. I've done everything to these things I could damn near write a book on it. Lol. The PCM replacement is not as hard as opening it up and going to the board. You do not have to do that. All of it can be done through OBD. ��

Also, sorry for any errors in my syntax in the last message... I'm using speech to text and Google. Still can't get it right. Haha

Quote:

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Originally Posted by roman123

No, not bench. I don't have OBD STAR; it reads these modules in bench mode. I used the Xprog M programmer to read the BCM and RHFUB. Yes, that's correct?to replace the BCM and RHFUB, I think these 5 bytes should be enough.

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how are you fixing the checksum though in the bcm/rf hubs after a vin change on a used module? seems like there's no good program that does them correctly...ive tried winols and ecu titanium and neither has the drivers or checksum plug ins for either.

Quote:

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Originally Posted by RoninDusette

Obd star is stupid expensive. It's like insanely expensive. You could go the next step down would be getting a vvdi prog and that would do it but they're like $400.. You don't necessarily need to marry the PCM like that. The proper way to do it would be to virginize The PCM and then have it pull that data from the body control module which there is a PCM replacement option in alpha OBD. If I'm not mistaken and you could do it all through the OBD2 port. The PCMS don't have any sort of lock like the RF hubs do if they've been updated or if they're like 2020 and up. I program Hellcat conversions all the time. I can program body control modules and everything almost completely through alpha OBD and it doesn't matter what year it is. Anybody that says you cannot write the BCM because it's locked or whatever or it's a one-time right? Only. Just look up the definition of what an eeprom is... It's right in the name it's electronically erasable which means it can be rewritten. If it can be locked or written by software. It can be unlocked and rewritten by software. That's all there is to it. I've done I think to date 23 Hellcat conversions of all different types. Anything from 2021 red eye swap into a 2015 Hellcat Challenger to a 2019 Hellcat conversion like the whole thing every last module. Every last little detail of it swapped into the 2014 300S. And all of it could be done but to do it the way that I do it in less than an hour. Those are all well. You know trade secrets... But it is all something that can be done. I mean hell. If you're in California I'll do it for you. Haha or I'll mail you the stuff. Pre-programmed. But as far as the PCM is concerned, you can use something like ECU hero or aemt Max and you can write like a blank eepron to it. That's still programmable and viable cuz it leaves the calibration data alone but the eeprom data will stay blank and virgin so that you'll be able to go in there and just do a PCM replacement and it'll automatically copy that stuff because all that stuff takes it from the network itself. So the body control module the ABS the RF hub. They have backups of all the other modules around them. So like when you go to replace the body control module not in a swap. But let's say you're just replacing a bad body control module. It's as easy as popping in a brand new body control module, turning the key on for 10 seconds. I usually wait 15 and turn the key off, pulling it out, locking the door and then waiting a couple minutes. Get back in. Everything is copied over. It's done completely automatically because it pulls that data from the RF hub and the ABS. A lot of people don't know that or are are completely unaware of how these networks work, but I spent the last couple years like obsessed with them and spending hundreds and hundreds of hours and I don't know how many thousands of dollars and trial and error. I mean you name it. I've done everything to these things I could damn near write a book on it. Lol. The PCM replacement is not as hard as opening it up and going to the board. You do not have to do that. All of it can be done through OBD. ��

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All this information is correct and accurate. But I shared it for those who don't have the original PCM and can't clone it. I didnt say this is the correct method. The proper way is to make it virgin, just like you said. This information is for specialists, not for car owners. I hope I didn't harm anyone's ability to make money.)))

Hello everyone, I am in the same position I bought a hellcat swap kit but the seller misplaced the ECU, I am a bit experienced in diagnostic scanners and some programming, and I read I can buy a micropod2 with a cda6 license to flash a used pcm and re write vin number? All other modules are intact (RFHUB; BCM; etc) So, any input in how to retrieve the eprom data from them and write it into the PCM would be fantastic.

Also, the seller sold me a regular hellcat (2018) Donnor car (It was flooded, mechanicals are fine but the electronics), so he shipped the modules from a redeye, so the first thing to do would be to match the used pcm correctly and then, can I just load the proper calibration file to run my 2018 hellcat?

I can tip a remuneration for any help that solves these doubts. TIA

I can put the correct flash file and change the vin for you. would be a lot cheaper then buying a Micropod and CDA.
If you have a 2015-2018 you just need the correct vin in all the modules and correct OS for the PCM.

hello Roman
i read rfhub, i found 6 bytes, i wrote the 6 bytes at the pcm same as you showed at the pictures but the car still have skim problem at the pcm and it doesn't start.

any help please?
thank you

so definitely nobody have done this job, only talking , the solution you posted, never worked

the only solution is buy new pcm from dealer and programming by micropod

Any time the data field is changed with anything vin security bytes part number of the module the crc needs to be recalculated ..this is like Roman said for more advanced users ..your not gonna be able to just copy and paste bytes and no one is gonna share how that's done either.

Quote:

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Originally Posted by shmuk

hello Roman
i read rfhub, i found 6 bytes, i wrote the 6 bytes at the pcm same as you showed at the pictures but the car still have skim problem at the pcm and it doesn't start.

any help please?
thank you

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If the dump structure is different from my solution, then you need to read SPC5606 in BCM and look for 6 bytes in mirrored form.

Quote:

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Originally Posted by shmuk

so definitely nobody have done this job, only talking , the solution you posted, never worked

the only solution is buy new pcm from dealer and programming by micropod

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Why should I post a non-working version?
I found this solution and my mechanic's car started.

Maybe your 6 bytes are not there.

Quote:

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Originally Posted by roman123

Why should I post a non-working version?
I found this solution and my mechanic's car started.

Maybe your 6 bytes are not there.

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That's right, it will only work if you know the key values. I program the control units through dealer access, it's more reliable and faster. But you're great, good job.

Just wanted to let you guys know this method does work. I got a 2019 scat pack in, customer got it with no motor or trans or ecm. Read the rf hub and wrote the 6 bytes to ecm and fired right up! Thanks for the info!

Hello can you please share archives again i click on it and it said no files found
I have a 2018 scat original pcm was stolen
Got a donor but needs sync thanks I advance!

Quote:

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Originally Posted by Lock713

Hello can you please share archives again i click on it and it said no files found
I have a 2018 scat original pcm was stolen
Got a donor but needs sync thanks I advance!

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On a 2018 all you need to the correct VIN added to the PCM. if you want to send it in to my shop we can take care of that for you.

Quote:

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Originally Posted by N2speed

On a 2018 all you need to the correct VIN added to the PCM. if you want to send it in to my shop we can take care of that for you.

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I already did that car still has invalid skim key in ECM

What is the calibration Number (OS) of the PCM that is currently loaded?