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Discussion Starter #1
My Commander hit 200k miles yesterday and things are going wrong. I have needed new cats for a while and am gettings those next week.
The newest issue appears to be the PCM.
Has anyone used one of the online dealers? the price of a re-man is tempting.
 

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O.K.....I'll ask....what is a PCM??


Basically it's the computer that controls everything. Used to call'em ecu's .

The computer for the commanders are so involved in out of my depth dealing with them. I see them online where they have to be programmed to the vin #


Sent from my iPhone using Tapatalk
 

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I've got one I'm going to be getting rid of soon. I have to send it off with my 5.7 ecu to get the 5.7 ecu flashed with some stuff off my 4.7 ecu. it probably wont be anytime in the next couple weeks but if you're interested in it let me know

Edit: It's off a 2008 Sport Flex fuel 4.7
 

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Basically it's the computer that controls everything. Used to call'em ecu's .

The computer for the commanders are so involved in out of my depth dealing with them. I see them online where they have to be programmed to the vin #


Sent from my iPhone using Tapatalk
ECU is a term I'm familiar with; I've never heard of it referred to as a PCM before.

Thanks for clarifying.
 

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Powertrain Control Moduel (PCM)
There are computer modules (which you could call ECU's) all over the Commander and they communicate over a data bus. The PCM is the one that controls the engine.

People often jump to conclusions when they can't figure out the problem and think the PCM is bad. But they do go bad. So for the original poster how do you know the PCM is bad?

For the guy that says he's getting a 5.7L PCM flashed to be 4.7L or at least have some of the 4.7L programming? How? The system is set up by part number that prevents you from flashing one set of software into another PCM, even if the PCM's are identical hardware wise. Are you sending it to some specialty shop that hacks PCM's?
 

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Powertrain Control Moduel (PCM)
There are computer modules (which you could call ECU's) all over the Commander and they communicate over a data bus. The PCM is the one that controls the engine.

People often jump to conclusions when they can't figure out the problem and think the PCM is bad. But they do go bad. So for the original poster how do you know the PCM is bad?

For the guy that says he's getting a 5.7L PCM flashed to be 4.7L or at least have some of the 4.7L programming? How? The system is set up by part number that prevents you from flashing one set of software into another PCM, even if the PCM's are identical hardware wise. Are you sending it to some specialty shop that hacks PCM's?
Just the mileage and VIN (So I can start my commander)

I'm in the process of an SRT swap.
 

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Just the mileage and VIN (So I can start my commander)

I'm in the process of an SRT swap.
Ah, yep, because of security and anti-theft immobility system, the PCM has to have the VIN# for the vehicle programmed into it. It compares the VIN# with the VIN# of other modules in the vehicle, if they are the same, it will allow the vehicle to start, if it is different the PCM won't let the engine start or run.


As far as I know, the dealer tool has to plug into the OBDII port to do this. Meaning, if you install the PCM yourself, the vehicle will NOT start and run, you would have to have it towed to the Dealership to have the VIN# programmed into the PCM.


The mileage is needed to get the Odometer to read correctly on Commanders, NOT true on all vehicles. Most of the later vehicles have the VIN# thing, but early vehicles, like '99, don't have to have the VIN# programmed into them to start and run the vehicle.
 
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