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Mike V.
Mike V., Auto Mechanic
Category: Dodge
Satisfied Customers: 25514
Experience:  25 years automotive expierience, Nissan factory trained, Subaru factory trained.
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Should I reprogram/reflash the car computer with a used PCM?

This answer was rated:

If I replace the PCM with a used PCM, do I have to reprogram/reflash the computer for the car to run?

Already Tried:
car has gray key so w/security. not worried about mileage being programmed into computer. just need to know if it actually requires reflashing or some trick to reset new/used computer. is it as simple as change the computer, start and drive. thanks.

Yes, the pcm will have to be re flashed for the car to run.Security settings as well as the VIN and millage will be reprogrammed as well.

Hope this helps!

Customer: replied 7 years ago.

I spoke to two different dealers w/ conflicting answers.

One says yes to reprogramming but it is to make sure the mileage on the computer matches the car and nothing else. The other dealer said i would have to " reset everything, it's not re flashing just a trick that our techs no how to do."

So it is i guess multiple parameters and security settings that do require reprogramming? again i am not worried about mileage.

No problem at all. Here is the info I have for it. Now,I am not saying that you can't give it a shot and see what happens, but I expect there to be some issues if you do. I totally understand about the mileage as well. If it was just that I don't think it would be a concern either.


Mike V. and 5 other Dodge Specialists are ready to help you

I am sorry, I just got some info from another expert. You can't change the vin on this pcm.
What he is saying is this. You don't have to re flash for the car to run. However you can't use a pcm from a car that had factory security.
If your car has the factory security, then you have to get a pcm from one that didn't have it and have the pin programmed into it for it to work.
If neither has the security,you can just swap them out and the car will run with no problem.
I got this info from an expert with more experience.