NGC or GPEC2?

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No venom, honest question. Do you understand how the CanBus networks function in newer cars?
In general yes....but there are multiple different communication lines in different manufactures like for example serial data, can low, can high, Lin bus, Most, etc but you get the point. I have diagnosed many communication problems over the years and some are much easier than others.
 
In general yes....but there are multiple different communication lines in different manufactures like for example serial data, can low, can high, Lin bus, Most, etc but you get the point. I have diagnosed many communication problems over the years and some are much easier than others.

Ok, just checking.
 
Ok, just checking.
That is why I said your in over your head because I have learned over the years and also been involved with other peoples deals but it is very hard to trick a system without there being side effects that people didn't realize it would affect.
 
That is why I said your in over your head because I have learned over the years and also been involved with other peoples deals but it is very hard to trick a system without there being side effects that people didn't realize it would affect.

Gotcha. My thought wasn't to trick the system, only to give it what it needs without having to use all the other stuff. But it does feed into my comment that "I don't know what I don't know" and the possibility that I am missing something. Never going to say I know it all.
 
This is exactly why I gave you the suggestion to run the A/C, old school style. You do realize, that besides the logic and inputs a PCM uses, all it does, ultimately, is ground the coil side of a relay to turn on the compressor? That is what an LSD (low-side driver) does. On an old school sytem, you can wire a switch on the dash, to do exactly that. Sure it wont be as efficient, but it will be far easier to work with, if you dont plan on using everything.To have the PCM run it requires more than you think. It can be done pretty easily by those who know and understand the operation of all the inputs (and outputs) used; but why ask all this or any of it for that matter, if you have a donor vehicle, from which to pull the entire system from and graft it in? There is no need to reinvent the wheel here,if you want the PCM to run everything, then just install the whole works. You don't have to worry about the anti theft system, if you use a PCM from a truck that was not equipped with one, which also points to my suggestion of NGC (as the easiest to locate). . Your dissertation on using the BUS showed you have at least some understanding of the theory behind it. Most of us that responded, probably understand bus communications well beyond that, which led us here to begin with.
 
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This is exactly why I gave you the suggestion to run the A/C, old school style. You do realize, that besides the logic and inputs a PCM uses, all it does, ultimately, is ground the coil side of a relay to turn on the compressor? That is what an LSD (low-side driver) does. On an old school sytem, you can wire a switch on the dash, to do exactly that. Sure it wont be as efficient, but it will be far easier to work with, if you dont plan on using everything.To have the PCM run it requires more than you think. It can be done pretty easily by those who know and understand the operation of all the inputs (and outputs) used; but why ask all this or any of it for that matter, if you have a donor vehicle, from which to pull the entire system from and graft it in? There is no need to reinvent the wheel here,if you want the PCM to run everything, then just install the whole works. You don't have to worry about the anti theft system, if you use a PCM from a truck that was not equipped with one, which also points to my suggestion of NGC (as the easiest to locate). . Your dissertation on using the BUS showed you have at least some understanding of the theory behind it. Most of us that responded, probably understand bus communications well beyond that, which led us here to begin with.

Not sure how I gave you the impression I have a donor rig, all I have is a short block with heads.

I’m fairly familiar with the JTEC controller due to planning to do a Magnum swap. Built my harness and had plans for using the BCM (drawing a blank on the real name) to run the built in security. Guess it was just a learning experience.
 
See, you missed it. The point was that I hit a switch on the dash and the PCM turns the clutch on and off as needed, just like it would in the 2010 Ram. Far as the motor/PCM/AC is concerned it is still in a truck.

Not sure how I gave you the impression I have a donor rig, all I have is a short block with heads.

I’m fairly familiar with the JTEC controller due to planning to do a Magnum swap. Built my harness and had plans for using the BCM (drawing a blank on the real name) to run the built in security. Guess it was just a learning experience.

Guess I incorrectly assumed by your statement above, you had a donor.
 
Guess I incorrectly assumed by your statement above, you had a donor.

Sorry, just an example. A “what-if”. If I go down the road of an OEM harness like I was doing with my Magnum swap, and it is an NGC setup, 2010 is the year I keep defaulting too when I look for parts.

To be clear, the talk about AC and all is just for future projects. I am trying to limit projects to stuff I can get done in a winter so getting the motor in is enough without trying to complicate things with AC. Worse yet, I want a 6M bad and if I use the Holley mounts it means I need to do them at the same time since the bell housing flange moves with those. So there is enough to do without adding more.

I’m only looking trying to make sure I don’t cut myself off from potentials mods in the future.
 
Finally (mostly) past the 5.9 swap into my Dakota and sold the harness and JTEC I built to do a Magnum EFI swap so started working on the PDC for my G3 swap. Discovered a couple of things in regards to the differences between an NGC and GPEC2 controller and thought I would post them here in case it helps anyone else.

The NGC controller does not have a radiator fan control function, much like the AC control mentioned earlier. The fan and AC are controlled by another module connected to the front PDC. So, the control of the fan will need to be done via a separate module much like AC will.

In comparison, the GPEC2 does control the fan to a degree. It has a control circuit, but in an LX/LC car, the non-HC models have a low and high speed fan and the function of turning those on and off is controlled separately. So a GPEC2 controller could turn a single radiator fan on and off, but if you wanted to run the OEM dual fan setup, it would require a separate controller.
 
Sure wish I could have gotten the pro's and con's of each controller instead of "run along little boy, you don't belong here". Guess sometimes you get what you get. Hope someone get's some useful info from this thread because I didn't.
 
Found out a couple of more bits of info.

The GPEC2A ('15+) controller does control the radiator fans. Still needs relays (of course) but it doesn't go through a TIPM with logic of it's own like the '14 and older cars. So just some extra relays but no additional fan controller required.

Also, for the '09-12 (I think) trucks, the cruise control switch on the steering wheel is hooked direct to the NGC4 controller while the similar vintage cars hook to the SCCM which puts messages on the CANBus network for the PCM to read. In both cases, an ABS module would be required for functional CC, but the trucks would (should?) be easier to make function. I spent a fair amount of time trying to sniff the CC messages and have gotten no where so far, but the truck hook up would only require some resistors and no network shenanigans.

Lastly, while I don't have absolute confirmation, I believe that the car NGC controllers can't just turn on the SRV controls and make that work. All of the 6.4 intake or motor swaps I have found so far have had to use an RPM switch to make it work. At the same time, '09+ truck NGC controllers have no problems running the SRV module on the 6.4 intake, or the truck intakes for that matter.
 
Found out a couple of more bits of info.

The GPEC2A ('15+) controller does control the radiator fans. Still needs relays (of course) but it doesn't go through a TIPM with logic of it's own like the '14 and older cars. So just some extra relays but no additional fan controller required.

Also, for the '09-12 (I think) trucks, the cruise control switch on the steering wheel is hooked direct to the NGC4 controller while the similar vintage cars hook to the SCCM which puts messages on the CANBus network for the PCM to read. In both cases, an ABS module would be required for functional CC, but the trucks would (should?) be easier to make function. I spent a fair amount of time trying to sniff the CC messages and have gotten no where so far, but the truck hook up would only require some resistors and no network shenanigans.

Lastly, while I don't have absolute confirmation, I believe that the car NGC controllers can't just turn on the SRV controls and make that work. All of the 6.4 intake or motor swaps I have found so far have had to use an RPM switch to make it work. At the same time, '09+ truck NGC controllers have no problems running the SRV module on the 6.4 intake, or the truck intakes for that matter.
All Good info - I have been going down this route for some time now. I have used 2005, 2008 NGC PCMs ( PCI & CAN) to do swaps. Understand exactly the challenges with A/C, Cruise and cooling Fans.
I am trying to use 2009 Dodge charger or 2012 Jeep GC ( NGC4A) to update a swap. In past only used a PCM.

Now with 2009+ I'm stuck on the Engine Start CAN signal required. Need to learn more about the CAN messages reguired by PCM so that it will turn on ASD, coils and injectors. I am able to generate and read CAN messges.... Don't know what to send . Can you help. ( FYI - I did same thing with PCI bus a long time ago)
 

All Good info - I have been going down this route for some time now. I have used 2005, 2008 NGC PCMs ( PCI & CAN) to do swaps. Understand exactly the challenges with A/C, Cruise and cooling Fans.
I am trying to use 2009 Dodge charger or 2012 Jeep GC ( NGC4A) to update a swap. In past only used a PCM.

Now with 2009+ I'm stuck on the Engine Start CAN signal required. Need to learn more about the CAN messages reguired by PCM so that it will turn on ASD, coils and injectors. I am able to generate and read CAN messges.... Don't know what to send . Can you help. ( FYI - I did same thing with PCI bus a long time ago)

You need to go into the PCM and turn off Start Signal on CANBus (or something like that).

But you still need to send the start switch signal to the PCM, and you have to wire a relay to the PCM so it can control the starter. So now the PCM get's a start signal via a wire, and then it knows to close the ASD relay to power the coils and injectors and it turns the motor over.

This video was very helpful to me.

 
I guess I was thinking that if I already had a computer in place, why not use it to control the AC (if possible). What I don't want to have to add another module, guess I will have to look further into it.

Honestly, AC knowledge is fairly weak for me beyond the basic principle of how it works. But I think most OEM EFI systems control the AC clutch so it can do thinks like turn it off when you go to full throttle. Could be that is all they do, don't know. Further research required.

Thanks.
With my Sublime harness, it does have an AC input trigger but I believe it is just that.. It allows me to utilize the factory engine harness, to control the AC wiring to the compressor. It routes through a seperate relay to keep any load off the ecm. I don't believe it turns off at WOT. The compressor that must be used is the single plug style and not the variable version, with 2 plugs. ANd turning the AC on, does not kick my fans on. My fans pretty much run constant, once it reaches temp.. so I just let it hit temp, which happens pretty quick, and then turn on AC. WHen I asked Blake if it could be set to control fans, he said it's possible through the SGA trans controller , but there's a few hoops. I could also add a relay to kick the fans on, off the AC trigger, but I'd need to add diodes so it doesn't backfeed into the ecm

Basically, you can run a wire from your panel, through a binary or trinary switch and to the compressor.
 
A far as GPEC2 vs NGC... Ask Chat GPT. I just did and it gave me a whole rundown and it turned into a rabbit hole that is far too much to explain LOL. I do know that the 2014 GPEC2 ECM is a brick. I have one on the shelf and it's good for nothing. It's the bastard of ecms. It's supported by HP Tuners but there's something about it that's different. It's my understanding that in order for the GPEC2 to be used in a swap, it basically has to be flashed to mimic the Mopar crate version of a ecm. There's body control modules, skim, cluster etc that are used in conjunction . The NGC doesn't link to any of that stuff.
 
Funny, I thought this was a different thread. I see what it is now. :D

With my Sublime harness, it does have an AC input trigger but I believe it is just that.. It allows me to utilize the factory engine harness, to control the AC wiring to the compressor. It routes through a seperate relay to keep any load off the ecm. I don't believe it turns off at WOT. The compressor that must be used is the single plug style and not the variable version, with 2 plugs. ANd turning the AC on, does not kick my fans on. My fans pretty much run constant, once it reaches temp.. so I just let it hit temp, which happens pretty quick, and then turn on AC. WHen I asked Blake if it could be set to control fans, he said it's possible through the SGA trans controller , but there's a few hoops. I could also add a relay to kick the fans on, off the AC trigger, but I'd need to add diodes so it doesn't backfeed into the ecm

Basically, you can run a wire from your panel, through a binary or trinary switch and to the compressor.

I guess I assumed that the Sublime kit would run it through the PCM. The wiring diagram I have for a '15-18 Charger shows the PCM controlling the AC clutch, but I probably assumed too much. As I look at it now, I don't see a way for the PCM to know that the AC has been turned on beyond the CANBus network so it's probably pointless to hook the PCM to the AC clutch if there isn't a way to tell it to turn it on. Maybe that's what Blake meant with the SGA controller, it could send the signal to turn it on?

I do know that the 2014 GPEC2 ECM is a brick. I have one on the shelf and it's good for nothing.

Is that the one you have been running and was missing the tables you needed?

It's my understanding that in order for the GPEC2 to be used in a swap, it basically has to be flashed to mimic the Mopar crate version of a ecm. There's body control modules, skim, cluster etc that are used in conjunction .

That was my conclusion as well. Best I can tell, if it weren't for the start signal being on the CANBus and the need for an SSR, it might be easier to use a GPEC2, but it's just a guess on my part. Either way, it's mostly why I ended up planning for an NGC controller.

Sure seems like an SSR shouldn't be that hard to do. I know Blake said in a video at some point (on FB maybe??) that the only currewnt source for an SSR was not a good solution and that if it doesn't fail, it floods the network with the message, clogging it up and making it impossible to use the OBD2 port to do anything. Sure seems like someone could easily build a module that sends the message like 5 time (or less?) when it get's voltage on a wire and then goes silent. But maybe I am over simplifying things.
 
Funny, I thought this was a different thread. I see what it is now. :D



I guess I assumed that the Sublime kit would run it through the PCM. The wiring diagram I have for a '15-18 Charger shows the PCM controlling the AC clutch, but I probably assumed too much. As I look at it now, I don't see a way for the PCM to know that the AC has been turned on beyond the CANBus network so it's probably pointless to hook the PCM to the AC clutch if there isn't a way to tell it to turn it on. Maybe that's what Blake meant with the SGA controller, it could send the signal to turn it on?



Is that the one you have been running and was missing the tables you needed?



That was my conclusion as well. Best I can tell, if it weren't for the start signal being on the CANBus and the need for an SSR, it might be easier to use a GPEC2, but it's just a guess on my part. Either way, it's mostly why I ended up planning for an NGC controller.

Sure seems like an SSR shouldn't be that hard to do. I know Blake said in a video at some point (on FB maybe??) that the only currewnt source for an SSR was not a good solution and that if it doesn't fail, it floods the network with the message, clogging it up and making it impossible to use the OBD2 port to do anything. Sure seems like someone could easily build a module that sends the message like 5 time (or less?) when it get's voltage on a wire and then goes silent. But maybe I am over simplifying things.
The 2014 ECM that I have, was in the charger that I scrapped. I kept the 5.7 for Hoopty. Blake didn't even want the ecm for free lol. I use it for mock up now. I can't remember exactly what it is with the 2014.. I think it was something in the skim. I did get all of my tables btw. HP Tuner pushed an update to me. Added 108 tables to my VCM editor.

As for SGAs ability to kick on the fans, ity has something to do with copying the signal code and placing it into the SGA as an input signal to kick the fans through the starlink canbus. It's been a while since I talked to blake about it, but that's my recollection. He's gotten pretty savvy with the SGA stuff and is supposed to be putting out some videos, like fan control etc. It's a time thing.. which nobody has
 
Is gpec2 29bit CAN and so very different ?? too new for me ...

I already have the unit to read CAN, PCI, CCD bus and control fans, CC etc and generate tach and VVS signals.
I want to add the CAN start signal message if I new what it was.
 
Is gpec2 29bit CAN and so very different ?? too new for me ...

I already have the unit to read CAN, PCI, CCD bus and control fans, CC etc and generate tach and VVS signals.
I want to add the CAN start signal message if I new what it was.
32
 
My bad.. You're right.
I thought CAN was 11 bit or 29 bit (extended)
I read a while back about it being 32.
I've got to stop relying on my brain...
 
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