PCM, how know what OS it has without connecting?

[general23cmp]

I have a 411 PCM from a 2002 Escalade. I’ve heard that depending on the time of year it was made, it could have one of two operating systems. The latter OS is more desired and allows for a 4L80e segment swap, which I’d like to do. Is there a way to look at a PCM physically and determine which OS is on it? For example, if I go to a salvage yard and find another PCM, can I tell if it has XYZ OS on it. I do see a calibration number stamped on the current PCM, but did not know if the same calibration can be found on different OS (or in my case, both OS).

I understand I can take my current PCM and change the OS, but that also takes more credits. I have a friend with a salvage yard and connections, so finding a better starting PCM is an option rather than burning through credits. I just need to know how to ID before connecting if possible.

[5FDP]

No, you have to read the computer to figure out the OS. A bench harness would make that easy.

Many vehicles would get OS changes when they went to a dealership for a service or a recall on the vehicle.

No matter what it will costs you credits if you don't have unlimited licenses. Either you get a different computer and license that or you use a GM tool to flash your computer with the OS you want and license the new file again.

[general23cmp]

Thanks. I haven’t plugged my current one in yet, so it could be the desired OS, but so far have used zero credits on it. So, if there was a way to know before, I was going to do that. I’m new to this (actually, not new, but been away a while)....does it cost any credits to simply plug in and read what OS I have?

[5FDP]

Nope, it only costs credits to license the file.

[general23cmp]

So I assume Hptuners cannot write the calibration/os over to my computer from a same year Escalade that had the more desirable OS?

[5FDP]

Yes, it can but this is where you run the risk of wasting more money.

First you have to license your computer, then you'd have to license the file with the OS you want. So we are at 4 credits already. You'd have to write that other OS into your computer which would create a new OS on your original computer. It's possible it will ask you to license this new file again that you created and it may be 6 credits now. The other risk is that something doesn't go right, things don't jive and it turns your computer into a door stop.

If possible it's always best to use a GM tool to flash the computer with the file you want and only license it once. If you know a guy it will probably be cheaper than the minimum $200 in credits you need to spend to try it the other way.



Things would be slightly different if you had unlimited licenses for GEN 3 trucks, but we won't have to get into that.

[general23cmp]

Thanks. You just gave me more detail that it almost answers a question I just asked elsewhere. So if I’ve never written/licensed my pcm and found the desired OS/cal on the repository, in order to entirely write it to my pcm, it’s going to hit me for 4 credits minimum?

I thought I read somewhere that the credits are tied to the SN in the pcm, which shouldn’t change. So, I wasn’t really expecting more credits as long as my pcm was the same. I know changing VINs has different credit rules.

Thanks again.

[5FDP]

Yes, it would cost you 4 credits to do that.

I think doing it the other way is the best option. Have the computer flashed with the OS you need and only license that, so it would be 2 credits plus the cost to have someone flash it with the OS you need.

[blindsquirrel]

The credits are tied to a code generated from a combination of a OS ID and the PCM serial. Change either one and the licensed code changes.

[general23cmp]

Thx all for the help