Another ECU swap question

[SSyellowSS]

I will say up front that I have been searching for days regarding the issue and still feel the need to come here for answers. My PCM died in my LSJ cobalt and already have a spare in hand from another LSJ cobalt. I know that I will burn two more credits for the replacement PCM. I also already understand that a security relearn and CASE relearn will be necessary. My question is in regards to writing to the replacement PCM. My thought is once the security relearn is complete that I can write entire my file from the old PCM to the new. Now, does it need to be a stock, unmodified tune or can I write entire my current tune file? Any insight would be appreciated.

Josh

[Dr. Nopps]

I'd swear I've seen someone that must have just preformed a write entire to the ECM from one of those cars on the workbench with their modified tune and it worked fine, probably saved them money. But there is no guarentee that works for everyone. He may have had his licences applied/set up differently, but it really didn't seem that way. This was with an 09 Cobalt Turbo with a 2010 file that got written entire onto it.

[SSyellowSS]

I am still digging so hopefully I find a thread like that. I am not worried about licensing as I know it will cost me two more credits for the replacement PCM. I just want to make sure that I can do a write entire of the modified tune from my old PCM to the replacement without some intermediate steps.

[Sapper]

I am in the same boat. A friends PCM in a swapped jeep fried 2 pins. We were able to get his tune from the original PCM using my desktop harness. Now I need to get his tune on to the the new PCM. His new one was reprogrammed to a 01 Silverado via GM MDI as a base tune to get the correct OS on it. He's a GM Tech and I work in parts. LOL But this HP Tuners is not my forte'.

I need to get his original tune loaded. Please post up if you figure this out.

[SSyellowSS]

Well one way or another I will have an answer this evening. Will report back.

[schpenxel]

Just read the new ECM, open the old tune as a compare file, open comparison viewer (ctrl+5), right click, select "copy over all differences"

And voila, you just copied all the settings from your old file over to the new.

[Markmx6]

That will only work if the two ECM have the same OS, correct?

On my 0411 swap for my 98 suburban I used the PCM from a 2002 v6 (If I rememeber correctly) and did a write entire of a repository tune. (I know that it is not recomended because you can't verify the quality of the tune, and that the wiring is pinned correctly for the operating system) It was my gamble that I was willing to take though... I didn't have the option due to OS differences. If they have the same OS then schpenxel is showing you the better way...

[schpenxel]

It will work regardless of OS, BUT if tables are different (say one tune has one MAF table and another has two MAF tables) then those differences won't transfer over. Only tables that are the same will transfer over using this method.. but if it's the same ECM usually they're close enough for almost everything to transfer.

[Markmx6]

That's good to know, Thank you

[Dave_62]

Just read the new ECM, open the old tune as a compare file, open comparison viewer (ctrl+5), right click, select "copy over all differences"

And voila, you just copied all the settings from your old file over to the new.

In this scenario, does the old tune have to be licensed, or can it be a unlicensed tune that was simply read and saved? (Assuming same hardware # and OS #)

[schpenxel]

Compare file can be any file, licensed or not doesn't matter