davepl

Dude it's not up to me to explain to you why you're wrong, I'm just trying to protect others from your uninformed misinformation. No need to follow me around and respond to every post I make.

It's flattering but considered stalking. So try to resist next time. Pretend you're here because of the cars, not me.

davepl

The answer is no (with a "but"). They can tell how many times, and whether it was an offical tune (flash part number), but if not, they don't know with what, just that it was non-factory. Duramax history is 10 deep, for example. PM me if it's important enough you need details.

So can they tell "precisely" what's been done? No, "but" they can tell what you didn't do (ie: you didn't use a factory signed calibration the 3rd last time, for example).

To be fair, however, I'm not really up to speed on the Gen V. I'd hoped this thread would help remedy that, but no one here really seems to know, so it's all attitude and posturing. The Camaro guys seem more adventurous with the Gen V ecm.

Higgs Boson

First answer no, second answer yes. You are correct.

You're the kind of person that needs his ego stroked and since I'm not doing it, you are now telling yourself this? And out loud on a public forum? Wow.

The sad part is, I can determine if you have a good day or a bad day.

Higgs Boson

Are you under the impression it takes more than that to deny a warranty claim? Sure you can claim whatever Act you want but when it's cheaper to just rebuild your engine than simply raise the point in court, what are you going to do? Be a man of principle?

"Looks like you monkey'd with the calibrations" is all it takes. They don't care if you swapped vins or swapped motors or turned the fan on 1 degree cooler.

My point earlier about an independent shop being "allowed/able" to swap ecms is not even in contention with your point but you make it to be, that's the only issue I have with you, you're just seemingly looking for a fight. Let me spell it out all the way for you so hopefully you don't try to find emotions.....an independent can swap ECMs.....but from a warranty perspective, why would a customer PAY an independent to swap ecms when it is free at a Chevy dealer when you have an issue? You wouldn't.....unless you're playing games. So if you replaced an ecm on a vehicle that's under warranty and paid an independent out of pocket then you have already implicated yourself by default. GM knows this, it's common sense.

And let's be real.....without being emotional, answer this question....Why do you want the ability to swap ECMs?

davepl

Sorry Higgs, you no longer impress or concern. Why randomize threads with your dime store psychoanalysis?

Like I said, get over yourself, get over me, and talk about cars. I don't really want every post I make to be haunted by your annoying ghost.

Go find something productive to do instead of sitting by your computer waiting for the beep when I post.

I've for $2 says you use Outlook and have a rule set up to flag my messages so you can get on top of them as soon as I post.

I've got a cool project I want to work on. I'd tell you about it, but you'd somehow make it about "feelings" and I'm bored of you, so I'll keep it on the other forum. Where people know their stuff, as opposed to your "random speculation dotted with personal attacks". I went to school with guys like you. They didn't turn out well.

Higgs Boson

Case in point.

Don't let me determine your experience. Let it go. As soon as you're over it then we both are.

Higgs Boson

You didn't go to school with guys like me, you couldn't get into my schools.

And to be totally honest, I don't care about your cool project either but I hope you impress yourself, you need it.

What's next, I can't come to your birthday party?

davepl

Rest assured you don't determine my experience. I find you entertaining. Before retiring I had to manage all kinds of people. You're what we call a "two slotter". One slot for a check to go in your door, one slot for the code/work to come back out, and the door stays closed so no one has to interact with you. I bet that hits pretty close to home when you stop and think about it.

Now, do you have anything to contribute technically, or are you going to persist in this weird obsession over me? I'm sure others are bored watching.

It's unfortunate, as I've learned some interesting (to me, anyway) stuff about GMLAN, CAN, J2534, factory tune logging, and so on. But the forum missed out on all of it because you're here.

Now have your childish little "last word" and I'll be back tomorrow to see what it was.

Higgs Boson

Hirohawa

It's sad how petty and combative the CF has gotten and how it was mistakenly thought that "Jealous C6 owners" and "Viper Trolls" were creating all the problems in the C7 Z06 section.

Too bad this thread can't be magically moved to "Other Cars" to hide the infighting.

Higgs Boson

It happens, nothing to be ashamed of. Just people being people, myself included, no one is above it, I have seen almost all of the frequent contributors on the forum get into it with others and sometimes I think, "Dang I'm not even part of this one!"

In fact, I think I have read a few threads with you bickering as well.

At the end of the day, not a bit of it matters.

Hirohawa

For certain I am guilty with mixing it up with people. But that is my point I fell like too many threads devolve into a fight or argument whether it be offense or defense.

People should be able to disagree without it going nuclear. It's just a car forum which we are all fans of at the end of the day.

Gengo

Sorry I read this thread.

But it I will try and contribute something to the original question.

While my my information isn't about the corvette, I think we can look at other brands as an example, since manufacturers have the same interests.

In the Audi and Mitsubishi world where I used to live, a new ECU appears to require some kind of key for a VIN, which exists to precisely to stop people from swapping ECUs. In fact, even the well known tuner APR has a key-based system to protect proprietary code.

While i I don't have technical proof I can point you to, it just seems logical that a manufacturer would take measures to defeat such a simple swap. You are not the first person to have had this idea.

Lastly, again not speaking for GM, but one story from an Audi warranty claim was that they checked the bolts which held the ECU and on the basis of the bolts having been removed, denied a powertrain repair.

So yes, a bit of doom and gloom and no tech but I think it's logical.

Resume internet fight!

pkincy

Actually the C7 forums are very very civilized and those of us that had C6Z06s and had to listen to the fighting over the root causes of the valve guide failures, hence engine failures, know that.

However I am on the side of "Spend the $165 and try it." Clearly the older pcms could be changed ***** nilly and also a tune was not then a warranty problem. Likely there is something in the newer computers that may make that difficult, but if the cost of finding out is that low, then it is worth trying and not even talking about.

I would expect that someone at the Tuning Software Companies knows the answer. The Q just hasn't been asked in the correct place and posed to people with the right knowledge yet. So this debate amongst folks that admit they don't have a clue is nothing but somewhat entertaining but will not result in any answers as Dave has concluded.

pkincy

Ok, some answers. Apparently there is something called a CVN number in the software. If it can be kept the same no reflash would show. Also apparently at least one of the sophisticated tuning software companies was able to tune a computer and keep the CVN the same. A competing company that wasn't able to keep the CVN the same apparently told the EPA and Company 1 had to for liability reasons remove this capability. So now the major tuner software companies all do change the CVN when their tune is loaded. Also apparently, some of the smaller hand held tuning device companies don't value their franchise as much and do use the "Same CVN" trick to fool Mother GM. Apparently many even advertise that this "no change CVN" is part of their device. The information I got named no companies either in the large tuning software providers or handheld providers.

So the deal is not the need for a spare ecm/pcm, but the need to flash with a tune that keeps the CVN (whatever that is). And apparently some of the device manufacturers are claiming their device is for "off road" use only and hence they can have the CVN correction built in without running afoul of the Govt.

Edit: If you have used a handheld tuner (that uses the CVN correction) alwaysflash back to stock if you are having any additional tuning done via other software. Apparently the new software tune will give a checksum error due to the handheld tunes CVN correction and possibly brick your ecm.

davepl

I know I don't appreciate the way this thread went. I not of the opinion that it's harmless, either. It's like graffiti or vandalism to me - a mindless crime of wrecking something for the entertainment of the perpetrator at the expense of the victim. That response will be criticized as too emotional, but it's apt, so TFB.

Back on the topic, however, since that's what I would prefer:

I would think that any third party tune is an off-road-only mod by definition. Doesn't matter who you are, I doubt Diablo gets an Executive Order number from CARB for their tunes (they could, that's not a statement of fact, that's an assumption on my part).

The dealership can see, so far as I can tell, the hash of the tune going back for the last 10 flashes. So they'll see in the history an "Unknown Tune" rather than "Declo Calibration Part Number X". If you've got a powertrain problem and a history that includes an unknown, I don't think you have a warranty.

I wonder if HPTuners licenses to VIN or internal ID? I assume now it's the latter, and that I'll still need two licenses. That actually obviates part of my initial intent (backup ECM using same license as live ECM, so long as both aren't in use at same time).

I'm not advocating it, because my intent is actually not to fool the dealership, but in theory if you had two proper tunes you could (for all I know) flash them alternating 11 times and overwrite the history of your bad tunes with valid ones, but that's a stretch. I figure if you mod your car and break something, admit it and fix it, don't try to hide it.

Now, does anyone know if the Body Control Module (BCM) keeps a history too? :-)

LSX Camaro

I have a guy that comes to my shop anytime I need a stock GM calibration installed when a module is replaced. He is an independent that has all the same equipment that a GM deal has. He told me that if you wanted to have an second ECU that you would also have to replace the BCM-Body Control Module and the Instrument Cluster. All 3 communicate together and share certain codes. The BCM is the gateway between the ECU and IPC. If you were to just switch the ECU out the coding would not match. Each time a switch is made it is documented in the computer. If you were to switch out with 3 new parts and keep them as a set it would work.

mdz06vetter

LSX is correct, which is kinda what I hinted it when this thread was relatively short / new. I mentioned there were "redundant" modules and they were "fail-over" which is basically what was described above.

HighBeta

A thorough answer. Thank you.

bigsapper

The CVN, in more general terms, is known as a hash function or fingerprint. It's a mathematical calculation of all the values in the tune. While its possible to generate the same hash with different values, it's extraordinarily rare, even with half the values present in the E92.

As alluded to in a post above, there apparently are tuning devices/tuners that are capable of re-writing the CVN to be the same as stock. But all that does is state that the signature of the tune is stock. The shop (or GM) has a simple ability to look at the tune itself and tell it's been modified even when the CVN matches a factory tune. Hell, HP Tuners has a compare feature that takes less than a minute to display the actual differences between two tunes.

At the end of the day, if you mod be prepared to self insure or defend why your mods are not at fault. Don't expect to break **** with mods and have Chevy foot the bill.