LMM Programming History & CVN's Explained

[GMPX]

Since the introduction of the LMM we have been getting many questions about the so called 'Programming History Tracking' and CVN's.
First, what is a CVN?, it's a 'Calibration Verification Number' which is really a fancy GM name for a type of checksum number used to validate a stock or modified tune.

To understand what this is all about you need to understand a little about checksums. A checksum in it's simplest form is a calculation of a range of numbers that must equal a known 'checksum' value.
For example assume our checksum = 10, if we add 2+2+2+2+2 the value equals 10, therefore our checksum matches. If we added 2+2+2+2+3 we get 11, therefore this would be a mismatch of the expected checksum of 10.
GM knows the expected checksums (or CVN's) of the various ECM segments, Fuel, Speedo, Engine etc. So when the ECM adds all the calibration data within a segment it must match a predefined checksum (CVN) value, if they don't match then either the calibration data has changed or there is an error with the flash memory.

If you go to this website - http://tis2web.service.gm.com/tis2web
You can enter in your VIN, choose the ECM as the module and you can then see the expected CVN's for each calibration segment.
This is what your local dealer will look for, the TechII is able to retrieve the checksums (CVN's) of each segment on the LMM, as far as your dealer is concerned these numbers must match what CalID shows, if they don't then the calibration data is not correct (not stock).
Below is a screen shot showing typical stock CVN's, these CVN's will match what CalID shows for these part numbers -
http://download2.efilive.com/Staff/GMPX/Stock.JPG

The next screen shot is what TechII will show on a tuned ECM -
http://download2.efilive.com/Staff/GMPX/Tuned.JPG

You can see in the second screen shot the part number 12628693 shows 9 different CVN's, this clearly shows this ECM has at some stage had many non stock tunes put in it.

The main problem with CVN's is they aren't a simple 2+2+2+2+2 = 10 style checksum as was shown above, they are what is called a CRC which can't be fooled. See here for more details - http://en.wikipedia.org/wiki/Cyclic_redundancy_check

Some of the common questions we are asked are -

Q - Can GM really detect if my LMM ECM has ever had a non stock tune even if I've put my stock tune back in?
A - Yes as the ECM will log the CVN's of the calibration segments each time it is reprogrammed and store them (up to 10).

Q - Can I just reflash the stock tune back in 10 times?
A - No, the ECM is too smart, it only updates it's internal list if the CVN is different to one already stored.

Q - Can the programming history be erased with TechII if I slip my mechanic a $100 bill?
A - No, the ECM does not allow the history to be erased for obvious reasons.

Q - Can the CVN's be fooled on a non stock tune?
A - No, CRC type checksums cannot be fooled within the constraints of the flash memory space / layout of the ECM.

Currently the LMM is the only vehicle this programming history is activated on, but it would be a safe bet this will expand in to all new models over the coming years.

This topic was previously talked about here -
http://forum.efilive.com/showthread.php?t=7461

Cheers,
Ross

[rcr1978]

Ross, now that you have explained it will there ever be any hope of erasing this with EFI live.

[GMPX]

Sorry, I don't want to say anything with any certainty on that just yet :angel_innocent:

The tough part is there is a number of very valid reasons you would want to erase the history, one such reason would be a used ECM pulled from a wrecked truck that had been tuned, but was to go in to a stock truck to replace a failed ECM. The stock truck in this case would have warranty voided because of what was done to the other truck in the past.
That would be like the ECM gets a bad credit rating with one owner, the next owner of the ECM happens to be Donald Trump but the bad credit stays, in that case the bad credit should be able to be wiped.
However, chances are 90% of people will only use it for the (IMHO) wrong reasons when disputing warranty claims.
It's a tough call because I fully understand where GM are coming from implementing this, but, it also catches out innocent parties. But I am not here to be the morals police.

Cheers,
Ross

[rcr1978]

Thans Ross, I understand were you are coming from especialy when some body blows stuff up with a big ass tune and expects GM to pat him on the back and say we gotcha covered. But when you go in for a simple ECM-BCM reflash and they give you the :bad: on any future warranty because you have a little history in the ecm that sucks.

[stacks04]

you wont see any info on clearing the data on an ecm for some time. logic tells me that until the lmm is done getting updates from gm, and the first models are done with the 100000 mile warranty you see it. because if an ecm fails under warranty gm pays any way so no need for a junkyard unit.

[69camaro5speed]

what happens if you read the stock tune then take that ecm out and get a differant ecm tune on that one if there is some warranty work needed or recall then put the stock ecm back in befor you take it to the dealer ?

[joecar]

what happens if you read the stock tune then take that ecm out and get a differant ecm, tune on that one, if there is some warranty work needed or recall then put the stock ecm back in before you take it to the dealer ?That is the "best" way to do it. :cheers:

[McRat]

Ross.

I'm getting the same CVN with a HEAVILY modified tune and with a stock tune flashed with a Tech2.

This is on a 2005 Duramax.

Seems the Tech2 doesn't "calculate" the CVN on this model, it just reads it. If EFILive does not alter those 2 bytes, it won't change? Dunno for sure.

If it's the ECM that is generating these CVN's and the Tech2 just reads their stored location, the ECM should have a value that tells the Tech2 where to look for these. Move the pointer?

[Cougar281]

IMO, the problem with the flash history isn't so much the people that blow something up with a huge tune then want GM to fix it, but the people that run a 65hp Predator tune (for example) and have the unfortunate luck of an injector hanging open and nuking a piston (again, for example). The problem is the tuner did not cause the failure, but because of the programming history showing a non-stock program, GM could/would tell you to pound sand.... I'm all for the "you play, you pay", but when something happens like an injector hanging causes a motor to fail and GM says no becasue you had *any* programmer, I don't agree with. JMO.

[Duramax 6.6L]

Ross.

I'm getting the same CVN with a HEAVILY modified tune and with a stock tune flashed with a Tech2.

This is on a 2005 Duramax.

Seems the Tech2 doesn't "calculate" the CVN on this model, it just reads it. If EFILive does not alter those 2 bytes, it won't change? Dunno for sure.

If it's the ECM that is generating these CVN's and the Tech2 just reads their stored location, the ECM should have a value that tells the Tech2 where to look for these. Move the pointer?


Currently the LMM is the only vehicle this programming history is activated on, but it would be a safe bet this will expand in to all new models over the coming years.

[Cougar281]

Currently the LMM is the only vehicle this programming history is activated on, but it would be a safe bet this will expand in to all new models over the coming years.

I think his point was that a heavily modded tune was showing a stock CVN...

[Duramax 6.6L]

I don't know this first hand, But a very good friend of mine that works at a Chevrolet dealer that is performance friendly, has never been able to tell if a truck has been programed, even with a hand help programmer. I know that this dealership has warranted a few transmissions and transfer cases, that were blown because of modifications. This dealer does not even care if you have a lift kit installed with oversized tires

I have sold to this dealer and they have installed quite a few finger stick / blocker plate combos.

[MMLMM]

current solution right now is the fry your ecm and tow truck in for service....yes, no?

[vortecfcar]

current solution right now is the fry your ecm and tow truck in for service....yes, no?

Don't click the 'Dealer Visit' button on the DVT panel until you blow out the dipstick tube.


:hihi::fluffy:

[Redline Motorsports]

I guess install a pre-computer controler, like Edge etc...., will beat that system......

[GMPX]

Ross.

I'm getting the same CVN with a HEAVILY modified tune and with a stock tune flashed with a Tech2.

This is on a 2005 Duramax.

Seems the Tech2 doesn't "calculate" the CVN on this model, it just reads it. If EFILive does not alter those 2 bytes, it won't change? Dunno for sure.

If it's the ECM that is generating these CVN's and the Tech2 just reads their stored location, the ECM should have a value that tells the Tech2 where to look for these. Move the pointer?

Pat, the LMM CVN system is a little more complex. The LLY does use a simple adding checksum system, not CRC, I think it is just reporting the adding checksum value to the TechII. Having said that, I thought it would change!
I know what you mean on fooling the ECM to just send back a known value, however, that means that we would need to know the CVN for EVERY segment GM ever released for the LMM and store them in the ECM somewhere, too hard.
Did you get my Email on this BTW?

Cheers,
Ross

[Cougar281]

Pat, the LMM CVN system is a little more complex. The LLY does use a simple adding checksum system, not CRC, I think it is just reporting the adding checksum value to the TechII. Having said that, I thought it would change!
I know what you mean on fooling the ECM to just send back a known value, however, that means that we would need to know the CVN for EVERY segment GM ever released for the LMM and store them in the ECM somewhere, too hard.
Did you get my Email on this BTW?

Cheers,
Ross

How about if EFILive was programmed to read the "current" GM CVN, then program it into the ECM with the redirect for the Tech2?

[GMPX]

How about if EFILive was programmed to read the "current" GM CVN, then program it into the ECM with the redirect for the Tech2?

My head hurts just thinking about that process :)

Without saying too much we've made some great progress with Bosch ECM's over the last few weeks. Once we get our full flashing working for these ECM's we will probably be able to offer a 'reset ECM' option. :grin:

Cheers,
Ross

[fire0021]

current solution right now is the fry your ecm and tow truck in for service....yes, no?

didint work on mine i put a completley new un modded ecm in my truck and it still showed all my old check sums from my previous ecm. wich meens to me the info is stored also somewhere else. ambey the tcm not sure

[Cougar281]

Probably not TCM.... GPCM would be my guess.

[MMLMM]

didint work on mine i put a completley new un modded ecm in my truck and it still showed all my old check sums from my previous ecm. wich meens to me the info is stored also somewhere else. ambey the tcm not sure

Maybe there hiding a flash drive in the water pump, lol

[ScarabEpic22]

My head hurts just thinking about that process :)

Without saying too much we've made some great progress with Bosch ECM's over the last few weeks. Once we get our full flashing working for these ECM's we will probably be able to offer a 'reset ECM' option. :grin:

Cheers,
Ross

Great to hear Ross, I hope you're ready for the 4.5L Duramax if/when GM decides to release it...:fluffy:

[nonnieselman]

Maybe there hiding a flash drive in the water pump, lol

Now theres a thought.......:cucumber:

[GMPX]

Great to hear Ross, I hope you're ready for the 4.5L Duramax if/when GM decides to release it...:fluffy:

I've only seen what they had at SEMA, beyond that I got no idea.

Cheers,
Ross

[LeadfootDuramax]

Is there a place where this is discussed in more detail with regards to the LBZ? I was close to purcahsing EFI live or PPE and came across this while researching. I just want to be sure I understand this before jumping in.

[GMPX]

For LBZ GM have not enabled programming history logging, it's only LMM.

Cheers,
Ross

[LeadfootDuramax]

Strange, the bulletin looked like it instructed GM to check the LBZ as well and walked them through the steps to do so.

[GMPX]

With my current TechII software (June 2008) when you try to read it on an LBZ the TechII errors and tells you that you have selected the wrong model. Who knows, maybe it's all changed again.

Cheers,
Ross

[Jasondt2001]

Ruh Roh... http://www.dieselplace.com/forum/showthread.php?p=2753335#post2753335

Any word on that 8.0 release of resetting ECMS??? LOL :)

[Chalky]

Ross:

I found this thread on Corvette Forum. I have an int erst in this situation as I now own a new Corvette. I also tend to put my faith in the folks here @ EFILive when it comes to my information.

http://forums.corvetteforum.com/showthread.php?t=2065961

I am no expert on this subject but it seems that some are advancing information that runs contrary to EFI's data regarding re flashing. The implication is that the competition to EFILive have the ability to alter factory tunes without affecting the CVN or that as long as the OS is not changed, no change is made to the CVN .

[bdr2008]

Is there any new news on the full reset of the ECM history??

[LBZ]

didint work on mine i put a completley new un modded ecm in my truck and it still showed all my old check sums from my previous ecm. wich meens to me the info is stored also somewhere else. ambey the tcm not sure

Has anyone else tried this to see if this is true with all of the LMM's or if this was an isolated case?

It might save a bunch of people money if this idea doesn't work.

[Trippin]

I did a back to back test today where I flashed a core LMM ECM with TIS and recorded the programming history. When the core ECM was installed in a truck, the programming history remained unchanged, meaning the core's programming history was there and did not match the history in the trucks original ECM, which had been previously violated with EFILive. :angel_innocent:

Flashing the core ECM with EFILive and a non-stock cal yielded a non-GM CVN #. :frown:

Flashing the ECM back to a stock cal using EFILive, yielded a factory CVN #. :D

However, flashing the ECM multiple times with a stock cal, doesn't increment the history count or listing.

[JoshH]

When the core ECM was installed in a truck, the programming history remained unchanged, meaning the core's programming history was there and did not match the history in the trucks original ECM, which had been previously violated with EFILive. :angel_innocent:So does that mean that the history is contained in the ECM alone? I'm having a little trouble following exactly what you're saying.

If someone were to flash an LMM ECM with a bench harness and swap it with the stock ECM in a truck that had never been tuned, when they put the original, stock, never tuned ECM back in would the history show the CVN from the modded ECM?

[Trippin]

So does that mean that the history is contained in the ECM alone?

Yes, in the ECM alone.


If someone were to flash an LMM ECM with a bench harness and swap it with the stock ECM in a truck that had never been tuned, when they put the original, stock, never tuned ECM back in would the history show the CVN from the modded ECM?

The history follows the ECM. If the ECM was modded the history will reflect the mod.

Swapping in a virgin ECM will show a virgin history.

[LBZ]

Yes, in the ECM alone.



The history follows the ECM. If the ECM was modded the history will reflect the mod.

Swapping in a virgin ECM will show a virgin history.

So this method should also work with an LBZ then correct?

[winter200]

Thanks Guy.

[Cougar281]

So this method should also work with an LBZ then correct?

As someone else put it, "The LMM is the only one so far that has this little gem".

[Trippin]

So this method should also work with an LBZ then correct?

According to the documentation only the LMM OS contains the history. I'll check some LBZ Ecms with the latest Tech 2 software tomorrow.

[GMPX]

I agree with Guy, the history stays with the ECM, I am 99% sure it is not stored in any other module in the truck.

LMM is the only vehicle to keep track, the option is not even TechII to read history from an LBZ.

Cheers,
Ross

[LBZ]

According to the documentation only the LMM OS contains the history. I'll check some LBZ Ecms with the latest Tech 2 software tomorrow.

Thanks Guy!

[bdr2008]

I am new to the EFI game so sorry, but can the history be cleared with EFI yet?? Future??

[MadMaxx61]

not yet and maybe never as the there is only a few reasons to clear it one is to rip off the General and the other is getting a used ECM to replace a faulty one in a stock truck.


So it may one day but I dont think it is on a list of things that needs to be worked on yet.

[GMPX]

The other thing to think about is this, 'If' everyone starts clearing the programming history GM / Bosch will probably respond with something even more sinister that makes programming next to impossible.
Bosch have this level of technology for BMW, it's already started to creep in to the Bosch MED9.6 Direct Injection ECM's in the HHR/Solstice. Nobody who tunes GM trucks for a living wants that to happen.

Cheers,
Ross

[rcr1978]

not yet and maybe never as the there is only a few reasons to clear it one is to rip off the General and the other is getting a used ECM to replace a faulty one in a stock truck.


So it may one day but I dont think it is on a list of things that needs to be worked on yet.

Here I go :bawl: again but here's one for ya! Your nice new LMM that maybe you just changed the tire size or something on with "EFI live" now new pretty truck won't start due to the security no start issue and your in a hurry taking the nice girly or kiddies somewhere. Do you think GM should give you the :banana: when you go in to get it reflashed on that particular issue and put the end to any warranty thereafter?

OK I'm done whining Keep up the good work guys and I also see your point about the end to all tuning but you guys have always been the type if there is a will there's a way.

[N0DIH]

Most definitely they could make our lives heck. I could give you tons of ideas how (won't for obvious reasons!). Look at Dodge, they are making it difficult right now, just the delay to get a solution out is proving to be slow going compared to what we have now.....



The other thing to think about is this, 'If' everyone starts clearing the programming history GM / Bosch will probably respond with something even more sinister that makes programming next to impossible.
Bosch have this level of technology for BMW, it's already started to creep in to the Bosch MED9.6 Direct Injection ECM's in the HHR/Solstice. Nobody who tunes GM trucks for a living wants that to happen.

Cheers,
Ross

[bdr2008]

In my situation I am not looking to ripp-off GM but I did have a PPE tune in my truck for about a week and didn't like it. I am now afraid that if something happens 2 years down the road that GM will say pound salt because of the history....Just a thought... Yes I do see your point, but if someone can make that software then someone can ..... you see... Great site!!!!!!!!!!!!

[GMPX]

Well, we can clear it, it's been done here on our test LMM ECM, part of the 'fun' was the challenge of being able to do it.
But I sat back and thought about what could result from allowing people to do it and really no good can come from it.

If you have made a change to 'just' the speedo section to adjust for wheel sizes then you should be safe with GM as the ECM will only store that the Speedo segment was changed. It is that smart, it knows what segment was changed.

I also understand in your situation bdr2008 that you would want it cleared.
I don't want to shelve the idea of doing it, but so far the only thing I can see it doing is getting EFILive sued or GM making it 10 times harder to program these vehicles. Currently compared to other manufacturers GM have made it reasonably open for programming, they could turn that around very fast, especially using Bosch ECM's.
Have a look what the Europeans have to do to program some of the Bosch ECM's -
http://www.evc.de/en/product/ols/bdm/default.asp
Yep, remove the bottom cover every time they want to program something as the OBD-II programming system the BMW's etc use is impossible to hack. GM could always go down that path too.

We will be at SEMA this year so I am sure we will get a feel for what we should do from users and industry people...GM have a stand there right!

Cheers,
Ross

[joecar]

GM currently has 2 motivating forces:
1. not getting sued by the EPA;
2. slowing down financial losses;

User flashing of the ECM makes GM unhappy wrt both points...
otherwise GM could not really care at all if users flashed.

[bdr2008]

Not sure if i understand yet, but does a piggyback system like the Edge show up in the history. Sorry I am not near as computer smart as the people on this site but I am slowly learning...

[MadMaxx61]

no the Edge will not show up as it does not tune your truck but fools the ECM.

[Sparky8370]

Well, we can clear it, it's been done here on our test LMM ECM, part of the 'fun' was the challenge of being able to do it.
But I sat back and thought about what could result from allowing people to do it and really no good can come from it.

If you have made a change to 'just' the speedo section to adjust for wheel sizes then you should be safe with GM as the ECM will only store that the Speedo segment was changed. It is that smart, it knows what segment was changed.

I also understand in your situation bdr2008 that you would want it cleared.
I don't want to shelve the idea of doing it, but so far the only thing I can see it doing is getting EFILive sued or GM making it 10 times harder to program these vehicles. Currently compared to other manufacturers GM have made it reasonably open for programming, they could turn that around very fast, especially using Bosch ECM's.
Have a look what the Europeans have to do to program some of the Bosch ECM's -
http://www.evc.de/en/product/ols/bdm/default.asp
Yep, remove the bottom cover every time they want to program something as the OBD-II programming system the BMW's etc use is impossible to hack. GM could always go down that path too.

We will be at SEMA this year so I am sure we will get a feel for what we should do from users and industry people...GM have a stand there right!

Cheers,
Ross

Well, what a quandary. If that's the way you feel, shouldn't you just recommend that we stop tuning our GM products, and stop selling efi live? That seems to be what you're advocating in this post. Yet we know you as one of the "tuning Gods" that brings us this product.

[GMPX]

If you paid $40K+ for something you should have every right to do whatever you want to your vehicle.
This whole concept runs along the same path as people 'chipping' Playstations, XBox's etc. People seem quite willing to accept that if they mess that up or the console dies (after it's chipped) then the manufacturer will not honor the warranty.
Take it one step further, lets assume you buy an aftermarket radio for your truck, you wire it up and it burns out a wiring harness in the truck because you did it wrong, should GM replace the harness under warranty? IMHO, No. GM's warranty is not there to also cover user 'experimentation'.
Whilst our software gives users the potential to 'safely' tweak the trucks tune for better power, MPG etc, you are also a few clicks away from causing major damage.
I'm not saying stop tuning your truck, chances are 95% of people tuning LMM's are just putting in a tune with some extra HP with better economy, that will probably not damage anything and will never cause any issues, but someone who is trying to spin the engine to 5000RPM with a 300Hp tune who races every weekend should be willing to accept that if / when it all turns bad they will accept GM won't cover the warranty.

Cheers,
Ross

[LBZ]

If......
......I'm not saying stop tuning your truck, chances are 95% of people tuning LMM's are just putting in a tune with some extra HP with better economy, that will probably not damage anything and will never cause any issues, but someone who is trying to spin the engine to 5000RPM with a 300Hp tune who races every weekend should be willing to accept that if / when it all turns bad they will accept GM won't cover the warranty.

Cheers,
Ross

Well on my calculator, this is the majority no? Why not let the majority rule and give them the option.

The guys that do the 300hp 5000rpm tuning will get caught anyhow when they try for warranty.

Let God sort them out is what I say!!:gossip:

[bdr2008]

It would be nice if GM would make the warranty an option!! Thats not going to happen, so I guess I will hope and pray that EFI can help those of use that are not the extreme. I agree that if you do major damage with a tune that dealers and tech. people will be able to tell with out any trouble, just don't want to see GM getting an easy out on something that they should be paying for.

[Cougar281]

It would be nice if GM would make the warranty an option!! Thats not going to happen, so I guess I will hope and pray that EFI can help those of use that are not the extreme. I agree that if you do major damage with a tune that dealers and tech. people will be able to tell with out any trouble, just don't want to see GM getting an easy out on something that they should be paying for.

Think of how much money they could save if they did that. I think the best option would be to be able to delete the drivetrain warranty, while keeping the rest (we know how flaky some of the electronics can be).

[Chalky]

Interesting thread and I can understand EFI's position regarding being sued. I also believe that someone will release a work-around sooner or later, possibly someone with little to lose. Our government has already shut down the makers/distributors of 02 sims.

Here is my position, I bought an 08 Z06 for the 5/100 warranty. Really wanted an 06 with the 3/36 warranty and would have bought an aftermarket warranty for the drivetrain.

I really have no desire to mod this car but would like to be able clean up AFR/PE a bit after adding new intake. The problem I have is what will GM tolerate if anything? My guess is nothing. With that assumption, yes, I would like the ability to cover my tracks with EFI once I go inside and do my tweaking. Otherwise EFI has become a paper weight for me.

If I understand this, GM now has the ability to look at the E38 as well as the LMM for modifications. I would like to be wrong on the E38 at least!

Paul and Ross, kind of a damned if you do and damned if you don't.

[GMPX]

Our government has already shut down the makers/distributors of 02 sims.

Paul and Ross, kind of a damned if you do and damned if you don't.

Exactly, it's not like this would sneak under the radar. It's easy to complain about 'your rights' etc, etc when it's not you that would potentially be the one getting sued from the might of GM, let's face, they could probably do with the money at the moment :grin:
Think of it this way, if I told you how it was done, would you be willing to start up a company that advertised and offered an LMM ECM reset service knowing the potential litigation of doing so.

I sort of feel like the kid standing on top of the roof with everyone yelling jump, jump, you'll be fine, then when you do everyone says, wow glad it wasn't me.

Cheers,
Ross

[dynarex]

well if you guys figured it out-chances are sooner or later other less ecm orientated guys will figure it out-but somehow it will be available sooner or later -so you might as well just go ahead and release it.the general and bosch arent that naive to think someone cant figure out how to clear the ecm-its just a test to see how long it would take-bosch/gm is gonna put a stop to this stuff soon-weather we like it or not
so i say release the hounds!:cheers:

[bdr2008]

I do understand and don't blame you a bit, but how is everyone doing the delete with out getting sued from the gov. or the EPA? Cover you own butt cause nobody else will. Trust me I know..... But I sure will be one who is cheering you on if you jump!!!!!!!!!

[Chalky]

Ross:

I do have some good news. I think I can put you in touch with a lawyer that would be willing to spend your very last dollar to prove your innocence.

[GMPX]

This industry does seem to be obsessed with the 'we were first' concept, it's not something I loose sleep over, so if another tuner was to offer history clearing first and in a months time after they did they weren't begging for change outside a pizza shop then I'd be happy to release it :music_whistling_1:

Cheers,
Ross

[The Neens]

Well, what a quandary. If that's the way you feel, shouldn't you just recommend that we stop tuning our GM products, and stop selling efi live? That seems to be what you're advocating in this post. Yet we know you as one of the "tuning Gods" that brings us this product.

I don't see it as a "quandary"...I'll continue to modify my vehicle(s) and happily deal with any issues that I am responsible for...It's called hotrodding and I'm willing to deal with consequences...

Those who aren't, perhaps you, should leave their vehicles stock...

[McRat]

My prediction is that the handheld market will defeat it, or diesel folk will switch to harness boxes. If I were a harness box company, I'd be solidly targetting the gasoline market about now.

[Chalky]

There is a tuner on the G8 forum who claims he has the technology and is using it in his tunes to arrive at the proper CVN even after tuning. He calls it a stealth tune. I didn't follow the posts far enough but so far, he has not been challenged.

If there is a void for this feature, someone will rush into fill it. Possibly someone with much less to lose and more to gain by being the first to market. It may already be starting. Paul/Ross have evidently shown that it can be done. It might have also been the easy part of the equation. :)

[fire0021]

I don't see it as a "quandary"...I'll continue to modify my vehicle(s) and happily deal with any issues that I am responsible for...It's called hotrodding and I'm willing to deal with consequences...

Those who aren't, perhaps you, should leave their vehicles stock...


x2.

[Chalky]

Well, we can clear it, it's been done here on our test LMM ECM, part of the 'fun' was the challenge of being able to do it.
But I sat back and thought about what could result from allowing people to do it and really no good can come from it.

If you have made a change to 'just' the speedo section to adjust for wheel sizes then you should be safe with GM as the ECM will only store that the Speedo segment was changed. It is that smart, it knows what segment was changed.

I also understand in your situation bdr2008 that you would want it cleared.
I don't want to shelve the idea of doing it, but so far the only thing I can see it doing is getting EFILive sued or GM making it 10 times harder to program these vehicles. Currently compared to other manufacturers GM have made it reasonably open for programming, they could turn that around very fast, especially using Bosch ECM's.
Have a look what the Europeans have to do to program some of the Bosch ECM's -
http://www.evc.de/en/product/ols/bdm/default.asp
Yep, remove the bottom cover every time they want to program something as the OBD-II programming system the BMW's etc use is impossible to hack. GM could always go down that path too.

We will be at SEMA this year so I am sure we will get a feel for what we should do from users and industry people...GM have a stand there right!

Cheers,
Ross

Ross:

Just reviewing this thread again and have a question for you. As it currently stands, do you know believe that GM may be leaving the door open for tuners such as EFILive by not embracing a stricter/more difficult technology in regards to ECM tuning?

If you do nothing, what is to stop GM from changing their technology again to make your current tuning package obsolete anyway?

[MMLMM]

I don't see it as a "quandary"...I'll continue to modify my vehicle(s) and happily deal with any issues that I am responsible for...It's called hotrodding and I'm willing to deal with consequences...

Those who aren't, perhaps you, should leave their vehicles stock...

Exacty, We make our own choices with the options givin to us.

Besides, GM/Bosh will lock up the ECM as much as they want to. They know it can be cracked, if they want to implement more security they can and will, other wise, there bacicly are getting the security "they're paying for" so to speak....


If I were to find a crack I'd publicly let it out, if they didnt like that, there problem for not making it tougher...Correct?

[GMPX]

Just reviewing this thread again and have a question for you. As it currently stands, do you know believe that GM may be leaving the door open for tuners such as EFILive by not embracing a stricter/more difficult technology in regards to ECM tuning?

If you do nothing, what is to stop GM from changing their technology again to make your current tuning package obsolete anyway?
Not so much leaving the door open but more hiding the door key under the mat. They don't use any encryption or compression systems in the programming process, some Bosch ECM's do, so the technology is there (at least from one ECM supplier). You are right, maybe the ECM used in the 4.5L Dmax will be locked down beyond anything we have seen before, I have no idea.
The reverse engineering process could be made considerably harder if they wanted to make it so. Thing is, everything is hackable, look at Vista, M$ said that nobody could hack the licensing, I think within days people were posting hacks for it!, imagine how much M$ spent trying to stop that happening.
You have to keep in mind the only reason GM now have this programming tracking is to stop bogus warranty claims, by removing this you are going to upset the General, surely.

As we learned from the O2 Sims company that got shutdown, disclaimers are apparently worthless.

We had a similar discussion on the DPF/Cat removal, yes it is illegal in the US to do this, but, as a real world example, there is a company in New Zealand fitting Duramax's to boats, they needed to remove VATS, DPF, CAT etc, sometimes there is genuine reasons to remove such items where it is not practical to use them or they are not needed.
What will be interesting is what happens with GM's ECM exchange process, normally if you buy a new ECM you can give them your old 'core' and get a discount, so does this mean the spare parts stores will be selling refurbished ECM's will a bad history or will Bosch erase it for them?

Either way, this is an interesting dicussion and it's good to see that our customers are divided on this issue too, I don't feel so bad.

Cheers,
Ross

[Sparky8370]

I don't see it as a "quandary"...I'll continue to modify my vehicle(s) and happily deal with any issues that I am responsible for...It's called hotrodding and I'm willing to deal with consequences...

Those who aren't, perhaps you, should leave their vehicles stock...

Not for you, for Ross. To release or not release, that is the question I was referring to.
Because, yes there are legitimate reasons to erase it. If the whole warranty gets voided because of a tune that did not cause damage, well that's BS.

Do you think GM will fail more legitimate claims because of this, or avoid more erroneous claims because of this. Just think if they had this technology in 2001.
Dear Valued Customer, We are denying your claim for warranty on your injectors because of your tow tune. There is no problem with our injectors, regardless of what you may read on the internet.
Wow, they could have saved a ton of money by ripping people off back then.
And I have an older vehicle. I don't care about warranty. I'm just playing devil's advocate here. When I play, I do pay.

[MMLMM]

......Thing is, everything is hackable, look at Vista, M$ said that nobody could hack the lic.....



Ross

:rotflmao:
1337

[The Neens]

If the whole warranty gets voided because of a tune that did not cause damage, well that's BS.


I completely agree...With my '05 & '07, I've had 1 stereo, 2 sideview mirrors, 2 headrests and 1 seat replaced...I'm fairly certain my tuning didn't have anything to do with the failures...

[LBZ]

I completely agree...With my '05 & '07, I've had 1 stereo, 2 sideview mirrors, 2 headrests and 1 seat replaced...I'm fairly certain my tuning didn't have anything to do with the failures...

I have your race tune, are you sure the headrests and seat weren't caused by your tuning??:grin:

[tjwong]

Not so much leaving the door open but more hiding the door key under the mat. They don't use any encryption or compression systems in the programming process, some Bosch ECM's do, so the technology is there (at least from one ECM supplier). You are right, maybe the ECM used in the 4.5L Dmax will be locked down beyond anything we have seen before, I have no idea.
The reverse engineering process could be made considerably harder if they wanted to make it so. Thing is, everything is hackable, look at Vista, M$ said that nobody could hack the licensing, I think within days people were posting hacks for it!, imagine how much M$ spent trying to stop that happening.
You have to keep in mind the only reason GM now have this programming tracking is to stop bogus warranty claims, by removing this you are going to upset the General, surely.

As we learned from the O2 Sims company that got shutdown, disclaimers are apparently worthless.

We had a similar discussion on the DPF/Cat removal, yes it is illegal in the US to do this, but, as a real world example, there is a company in New Zealand fitting Duramax's to boats, they needed to remove VATS, DPF, CAT etc, sometimes there is genuine reasons to remove such items where it is not practical to use them or they are not needed.
What will be interesting is what happens with GM's ECM exchange process, normally if you buy a new ECM you can give them your old 'core' and get a discount, so does this mean the spare parts stores will be selling refurbished ECM's will a bad history or will Bosch erase it for them?

Either way, this is an interesting dicussion and it's good to see that our customers are divided on this issue too, I don't feel so bad.

Cheers,
Ross


Hi Ross, I am new to this board but I have been actively tuning cars since long before EFI Live, HPT or other OBD2 software pacakges. Way back when there was still removable proms in the ECMs that were used in the GM cars and trucks. I tried to protect my tunes on some cars by changing the check sums so that the commonly available tuner software such as TunerCat wouldn't ID the the binary file. Of course for the people that were good enough it was very easy to defeat my little modified check sum trick.

Since then now we have this CVN issue. Warranty issues for me is not an issue. I know if I mod my engines internals my warranty is done which is exactly what I have done to a brand new Z06. I also have customers that have brought their cars to me with less than a 1000 miles on them to have me install a Magggie blower kit or another with a brand new C6 Convertible that I recently installed a LS7 engine with a wet sump lubrication system. These customers are obviously not concerned with warranty concerns.

My issue is that 99% of my customers drive their modded cars on a regular basis. So my concern is them passing their annual or bi-annual emissions test so that they can license their cars. I realize that by the book a heavily cammed engine with ported heads, and headers won't be passing a SMOG inspection, this is especially true in the Republic of California where even headers are illegal. However do to the corrupt there is even a go around for headers if one has the cash :lol: So what I am concerned with is if the EPA or the local authorities mandates that their inspection programs start checking CVNs, then the entire business of doing this sort of work is at stake. I have heard that California is already checking CVNs but I have not verified that at this time. I can see the writing on the wall, that it is most likely coming. As one member already mentioned, one tuner who is in Michigan is already creating custom tunes that has the correct CVNs. So the hack is done, but yet to be implemented in the commonly available software.

Just how hard is it to crack their CVN strategy? I am going to SEMA this year, perhaps if you are there I would like to meet and talk. I worked for a couple Austrailian firms in my old engineering days. One of them is Austrailias largest paper manufacturers. I helped to design and build a 100% recycle paper mill in New Mexico for them. I was responsible for engineering the plants process control system.

[joecar]

TJW, welcome to the forum... :cheers:

[GMPX]

Hi TJW, thanks for your input. I too remember the days of UV light tuning :-) , it was easier back then. The size of two spark tables in the E38 is about the same size as a whole engine calibration from days gone by.

Whilst I can't speak on behalf of the Governator I am sure that since selling he's Hummers (which were probably tuned) that the idea is to stop people modifying their cars totally so they meet the emission requirements GM are forced to comply with as long as possible. But the after market is too big to let that one get through, surely?

Keep in mind that the ECM is just running a computer program written by humans, so, that means another human can modify it to do something different. That is not really the problem (for us), it's the concept of knowingly bypassing that where the problem is.
Even by fooling the CVN's you are treading on deadly ground.
It would be quite simple to hack the ECM code to report whatever CVN you wanted it to, but somewhere down the line someone at GM might figure out what is going on and then you are back to this issue of knowingly bypassing a check GM / EPA have put in place to detect tuned vehicles. In the eyes of the EPA that is probably as bad as pulling the cats off and running AVGas.

Yes we are at SEMA, please feel free to call by our booth, we will be in the main hall.

Cheers,
Ross

[Trippin]

According to www.semashow.com (http://www.semashow.com) EFILive will be in SEMA booth 21951 in the "Racing and Performance" section. :)

Ross,

It occurred to me that when EFILive releases the full reflash capability for the LMM ECM, (Before SEMA right?) we could then alternate flashing different stock calibrations and OS# until the history is filled with legit CVNs. :angel_innocent:

Are you listening Paul? :pokey:

Anyone?

Anyone?

Bueller?

[Sparky8370]

How many flashes does the history hold? Does it record dates or other info besides cvn number? That could take a while.

[joecar]

I wasn't paying attention (or I forgot... I dunno which...)... what happens after the 10th [different] flash...?

[1998ws6]

After the 10th flash, the last one is not displayed, and a new one is stored in its place.

The CVN and the part number are both shown at least with current tech 2 software. Since there seems to be only 2-4 correct OS ID's for any given LMM/LBZ vehicle. It is unlikely you could get 10 correct, in sequence updates to reflash in order to fake a dealer.

While there are several correct enigne calibration sections, a dealer could still question why your pcm had engine operations history from a van, kodiac, and truck all in history.

The company in michigan also locks the pcm/tcm, so dealer would know really quick that something was up if they went to reflash it.

[tjwong]

After the 10th flash, the last one is not displayed, and a new one is stored in its place.

The CVN and the part number are both shown at least with current tech 2 software. Since there seems to be only 2-4 correct OS ID's for any given LMM/LBZ vehicle. It is unlikely you could get 10 correct, in sequence updates to reflash in order to fake a dealer.

While there are several correct enigne calibration sections, a dealer could still question why your pcm had engine operations history from a van, kodiac, and truck all in history.

The company in michigan also locks the pcm/tcm, so dealer would know really quick that something was up if they went to reflash it.

Does that companys name start with a "V".......and they thought that they were so sneaky with their stealth tune and the correct CVNs :laugh:

[Chalky]

This industry does seem to be obsessed with the 'we were first' concept, it's not something I loose sleep over, so if another tuner was to offer history clearing first and in a months time after they did they weren't begging for change outside a pizza shop then I'd be happy to release it :music_whistling_1:

Cheers,
Ross

Does this count?

http://www.vectormotorsports.com/index.php?option=com_frontpage&Itemid=1

http://www.g8board.com/forums/showthread.php?t=4684

[bdr2008]

I just had the truck in two weeks ago to have the reflash. Nothing was said, but is that info. stored at GM for the future that they could look back at in the future if I had a major break down? Was it downloaded and stored????

[GMPX]

http://www.vectormotorsports.com/index.php?option=com_frontpage&Itemid=1

http://www.g8board.com/forums/showthread.php?t=4684


Well, first thing is this is not for a Bosch ECM, that is a very important point!
But I'll give them credit where it is due, the fact that they don't turn off the checksums and still have the matching CVN is good.
But the point I am trying to make is bypassing all these 'checks' GM puts in will only keep us safe for so long.

Cheers,
Ross

[Sparky8370]

Well, first thing is this is not for a Bosch ECM, that is a very important point!
But I'll give them credit where it is due, the fact that they don't turn off the checksums and still have the matching CVN is good.
But the point I am trying to make is bypassing all these 'checks' GM puts in will only keep us safe for so long.

Cheers,
Ross

So that's how you'd do it?

[tjwong]

Well, first thing is this is not for a Bosch ECM, that is a very important point!
But I'll give them credit where it is due, the fact that they don't turn off the checksums and still have the matching CVN is good.
But the point I am trying to make is bypassing all these 'checks' GM puts in will only keep us safe for so long.

Cheers,
Ross

Ross, it is kind of like the hacked Direct TV H and HU cards a few years back. Some one hacks the code, then everyone can get free satellite TV, then Direct TV blasts the hacked cards with a signal wich renders them useless, then someone else comes up with a new hack and the cycle goes on and on. Finally Direct TV got a hold of some of the records of where the hacker equipment was sold and Direct TV hired lawyers to sue people for theft of services, some caved in and paid off DTV others held out and won. I see this coming to our world now and its only going to get worse as rules tighten up in the world of the EPA standards that govern the OBD2 regulations.

[GMPX]

So that's how you'd do it?
Not how I would do it, having the checksums functional is pretty important, but it could be done that way.


Ross, it is kind of like the hacked Direct TV H and HU cards a few years back. Some one hacks the code, then everyone can get free satellite TV, then Direct TV blasts the hacked cards with a signal wich renders them useless, then someone else comes up with a new hack and the cycle goes on and on. Finally Direct TV got a hold of some of the records of where the hacker equipment was sold and Direct TV hired lawyers to sue people for theft of services, some caved in and paid off DTV others held out and won. I see this coming to our world now and its only going to get worse as rules tighten up in the world of the EPA standards that govern the OBD2 regulations.
Exactly, they could make this whole tuning game too hard for companies like us. Piss them off enough and they will, that is how I view it.

Cheers,
Ross

[joecar]

The OEM 's have very strong motivations for preventing hacking:
1. EPA is on their case (the EPA can prevent the OEM from selling vehicles in USA),
2. Loss of revenue from warranty misclaims.

[bdr2008]

Jump Jump Jump!!!!!!!!

[Chalky]

Not how I would do it, having the checksums functional is pretty important, but it could be done that way.


Exactly, they could make this whole tuning game too hard for companies like us. Piss them off enough and they will, that is how I view it.

Cheers,
Ross

The point I am making is that others have already made work arounds available. Others will follow.

[bdr2008]

Can anyone tell me can they tell how long or when the tunes were installed?

[GMPX]

The point I am making is that others have already made work arounds available. Others will follow.

If it becomes common amongst tuners then we will follow too, but right now we don't know the impact of this 'bypass'. I'd rather not be the one poking the hornets nest right now thanks.

Cheers,
Ross

[N0DIH]

Thank you....


If it becomes common amongst tuners then we will follow too, but right now we don't know the impact of this 'bypass'. I'd rather not be the one poking the hornets nest right now thanks.

Cheers,
Ross

[jchev502]

If it becomes common amongst tuners then we will follow too, but right now we don't know the impact of this 'bypass'. I'd rather not be the one poking the hornets nest right now thanks.

Cheers,
Ross


Ross thanks for working hard on all of are needs with EFI, kicking the hornets nest is not what we need. Nice info on LLM and what we can all exspect down the road, I have a LBZ and hope your right on tracking LMMS only by GM.

[Chalky]

If it becomes common amongst tuners then we will follow too, but right now we don't know the impact of this 'bypass'. I'd rather not be the one poking the hornets nest right now thanks.

Cheers,
Ross

:)<

[GMPX]

Oh and by waiting for others to test the water doesn't mean waiting to see how it's done. Spoofing CRC's is common enough, it's not exactly 1+1 maths, but it's possible to do.

Cheers,
Ross

[schuter]

Well, we can clear it, it's been done here on our test LMM ECM, part of the 'fun' was the challenge of being able to do it.
But I sat back and thought about what could result from allowing people to do it and really no good can come from it.

If you have made a change to 'just' the speedo section to adjust for wheel sizes then you should be safe with GM as the ECM will only store that the Speedo segment was changed. It is that smart, it knows what segment was changed.

I also understand in your situation bdr2008 that you would want it cleared.
I don't want to shelve the idea of doing it, but so far the only thing I can see it doing is getting EFILive sued or GM making it 10 times harder to program these vehicles. Currently compared to other manufacturers GM have made it reasonably open for programming, they could turn that around very fast, especially using Bosch ECM's.
Have a look what the Europeans have to do to program some of the Bosch ECM's -
http://www.evc.de/en/product/ols/bdm/default.asp
Yep, remove the bottom cover every time they want to program something as the OBD-II programming system the BMW's etc use is impossible to hack. GM could always go down that path too.

We will be at SEMA this year so I am sure we will get a feel for what we should do from users and industry people...GM have a stand there right!

Cheers,
Ross


So could a guy just reprogram 10 times with different tire size each time.......

[DURAtotheMAX]

So could a guy just reprogram 10 times with different tire size each time.......


no I dont think so because that would only change the speedometer segment...? I might be totally wrong

ben

[GMPX]

It does seem to be hit and miss when it logs a change (which is weird), if you changed the speedo segment 10 times then 'in theory' that should work, but I found that sometimes it didn't seem to log a change to other segments.

Cheers,
Ross

[rcr1978]

Would you guys ever have the ability to read the last 10 cals with EFI live?

[GMPX]

CVN display is being written in to V2's firmware right now, I'll see if Paul might be able to add that too.

Cheers,
Ross

[rcr1978]

Thanks guys!

[GMPX]

Sorry, but CVN display on the V2 didn't make it in to the next release, next time.

Cheers,
Ross

[RayMich]

I did a back to back test today where I flashed a core LMM ECM with TIS and recorded the programming history. When the core ECM was installed in a truck, the programming history remained unchanged, meaning the core's programming history was there and did not match the history in the trucks original ECM, which had been previously violated with EFILive. :angel_innocent:

Flashing the core ECM with EFILive and a non-stock cal yielded a non-GM CVN #. :frown:

Flashing the ECM back to a stock cal using EFILive, yielded a factory CVN #. :D

However, flashing the ECM multiple times with a stock cal, doesn't increment the history count or listing.

What would happen if you were to alternate between two legal stock CALS? Could you then end up with the CVN history looking something like this?

AAAAA
BBBBB
AAAAA
BBBBB
AAAAA
BBBBB
AAAAA
BBBBB
AAAAA
BBBBB


I wonder if that would work.

[GMPX]

Probably might, then you would need to explain why your ECM has had so many different factory tunes programmed in to it.

[1998ws6]

That should not work, but I can give it a try. The information I heard states the engine cal OS CVN only gets written, if it is not one of the last 10 in memory

[GMPX]

Well, I can tell you that there is STILL a bug in the way TechII displays the CVN v's the segment, the numbers are jumbled compared to the order shown on CalID. You need to do this crazy cross reference to match up the segment to the CVN.
I'm sure in my testing I have also seen speedo segement updates be recorded in the history list, though for some reason that does seem hit and miss too.

Cheers,
Ross

[RayMich]

That should not work, but I can give it a try. The information I heard states the engine cal OS CVN only gets written, if it is not one of the last 10 in memory
It is possible that it may not write a CVN if it already exists, but I would think that at the very least, the current Cal (the last one programmed) and its corresponding CVN would be the last one showing.

It sure would be interesting to see what would happen in a situation where two stock cals are alternated.

If this works and they asked why the same two cals so many times, one could say that you were testing driveability differences between the two cals. :angel_innocent: :grin:

[ECUoutlet.com]

Those of you worried about this please note that we stock the 2007.5-2010 ECM's by the CASE at a rate considerably lower than dealer cost and lower than others selling used ones as cores! If you need an ECM we'll be happy to flash one to OEM specs with the up to the minute release for your use as a spare or one to tune so you can save your stock one for dealer trips.

We picked up a TON of these just for this issue so if you need one please let us know!

[RayMich]

Those of you worried about this please note that we stock the 2007.5-2010 ECM's by the CASE at a rate considerably lower than dealer cost and lower than others selling used ones as cores! If you need an ECM we'll be happy to flash one to OEM specs with the up to the minute release for your use as a spare or one to tune so you can save your stock one for dealer trips.

We picked up a TON of these just for this issue so if you need one please let us know!
Do you carry ECM's for the 2006 LBZ's? If so, how much are they?

What would you need in order to program one with all the latest OEM specs for a particular truck?

Thanks.
-Ray-

[ECUoutlet.com]

Currently we do not carry them, we are looking at the possibility of carrying them however buying them in bulk this long after production is over is more than likely impossible. If we can get a few we will of course post up.

Programming wise the only thing we would need is your VIN.

[RayMich]

OK.

Please, let me know if you are able to get one.

Thanks.

[ECUoutlet.com]

Will do, thanks for the interest!

[LBZ]

ok.

Please, let me know if you are able to get one.

Thanks.

x2!!

[bdr2008]

Anything new on this subject?

[GMPX]

You mean getting LBZ ECM's or clearing the programming history?
On the LBZ ECM's, not sure, on the programming history you might want to have a read of this thread to know it won't happen with EFILive.

http://forum.efilive.com/showthread.php?t=7657&highlight=CVN&page=4

Read my post on the CVN correction removal from the software.

Cheers,
Ross

[Jasondt2001]

Here's something on the LBZ (and LMM):


INFORMATION

Bulletin No.: 08-06-04-006C

Date: October 29, 2008
Subject:
Information on Identifying Non-GM Calibration Usages for LBZ, LLY, LMM Duramax(R) Diesel Engine

Models:
2005-2009 Chevrolet Express, Kodiak, Silverado
2005-2009 GMC Savana, Sierra, TopKick

with 6.6L Duramax(R) Diesel Engine (VINs D, 2 , 6 - RPOs LBZ, LLY, LMM)

Supercede:

This bulletin is being revised to add the 2009 model year. Transmission programming information on potential Non-GM ECM Calibration or Power Up Hardware that does not involve ECM reprogramming was added. Please discard Corporate Bulletin Number 08-06-04-006B (Section 06 - Engine/Propulsion System).
Caution: Customers should be informed that even after the calibration has been returned to a GM certified configuration, it is likely that engine, transmission, transfer case and/or other driveline components were weakened to the point of premature failure while subjected to the higher stresses from the non-GM calibration (Power-Up Kit). Engine, transmission, transfer case and/or other driveline components where a non-GM engine calibration has been verified are not covered under the terms of the New Vehicle Warranty.

Power-Up Kit Detection - All 2007-2009 RPO LMM

For 2007-2009 applications, an Engine Control Module (ECM) algorithm was implemented that records the engine calibration part number and Calibration Verification Number (CVN) for the last 10 flash programming events. The ECM only records the engine calibration part number because it contains the parameters for increasing torque and fueling rates.

Some customers may have re-programmed the ECM with a non-GM released calibration. The (Power-Up Kit) powertrain calibration changes fueling and timing parameters and likely contributes to the following vehicle conditions:
^ Poor Performance

^ Black Smoke (This symptom is not valid for the 6.6L (LMM) diesel equipped with the diesel particulate filter (DPF). The DPF will trap black smoke unless the DPF is cracked, melted or has been removed from the exhaust system.)

^ Knocking Noise

^ Engine Damage (Refer to Service Bulletin Number 06-06-01-007 for additional information.)

If a vehicle comes in for service for a driveability/powertrain concern as a result of a Power-Up Kit installation, the dealership technician now can read the last 10 engine calibration part numbers and CVN history using a Tech 2(R).

The dealership technician would input each ECM calibration part number into the SPS/TIS2WEB CVN database to confirm the CVN history information. Refer to Tech 2(R) path table in this bulletin to verify ECM calibration.

2007-2009 LMM Tech 2 Powertrain Output Controls Path Table for NON-GM ECM Calibration
1. Build the vehicle with the Tech 2(R).

2 Select F0: Engine Control Module.

3. Select F5: Module Identification Information.

4. Select F1: Programming History.

5. Turn Ignition On and Engine Off. Press ENTER Key to Continue.

Important: An original production engine operation part number programmed in the ECM from the supplier, which is the last part number shown, would not be in the SPS/TIS2WEB database.

6. Record the Calibration I.D. Numbers and Verification Numbers from the Tech 2(R) Vehicle Information/Programming History Screen. If the list of Calibration Part Numbers is less than 10, the first Calibration I.D. Number (bottom of the list) will not be in SPS/TIS2WEB. In this case, the first Calibration I.D. Number is programmed at the Engine Control Module production factory and is re-programmed at the vehicle assembly plant.

7. From SPS/TIS2WEB, record the Calibration Part Number into the CVN Database. Get CVN.

^ If the CVN does not match the CVN database, an unauthorized engine calibration part was flash programmed into the ECM.

^ If the CVN matches the CVN database, we can assume a Power-Up Kit that flash programs engine calibrations was not used.

2005-2007 LLY and LBZ Instructions for Confirming Calibration Verification Number (CVN)
1. Go to TIS2WEB

2. Select "Calibration Information (SPS Info)"

3. Enter VIN

4. Select "Get Cal ID"

5. Select "ECM Engine Control Module"

6. Select "Next"

7. Select "Complete History"

8. Print

9. Take the printout to the vehicle along with the Tech 2(R)

10. Plug in the Tech 2(R)

11. Go to diagnostics and build the vehicle

12. Select "Powertrain"

13. Select "Engine"

14. *Select "Engine Control Module"

15. *Select "Module ID Information" or "I/M Information System" if module ID information selection is not available.

16. *If "I/M information System" was selected in step 15, it may be necessary to select "Vehicle Information" in order to display the calibration information.

17. Compare the calibration ID and Calibration Verification Numbers (CVN) to the Calibration Verification Numbers (CVN) on the printout.

* Steps may vary by controller.

Although the part numbers will be the same for each, it's the CVN that will determine if the calibration is GM issued. If ALL of the CVN's are EXACTLY the same, the calibration is GM issued.

If the part numbers match and ANY CVN's DO NOT match the printout, it is likely that a non-GM certified calibration has been installed.

If the CVN information is displayed as "N/A", it will be necessary to contact the TCSC to obtain the CVN information.

If a non-GM calibration is found to be in the ECM (CVN's on the Tech 2(R) do not match TIS printout) - In order to document the case -- a CLEAR digital picture should be taken of the Tech 2(R) screen showing the VIN and the CVN's (Programming History Calibration ID and Verification Numbers) that do not match the TIS2WEB printout. A copy of the digital pictures showing the Tech2(R) Vehicle Information/Programming History Calibration ID Numbers, Verification Numbers, Transmission Data, Tech2(R) VIN and reason the vehicle is currently in for service should be emailed for verification. Please copy your GM District Service Manager (DVM) in Canada (DSM) on the e-mail. GM will verify if the CVN's are not GM issued and respond via e-mail within 72 hours.

Tech 2 Transmission Data Path Steps for potential NON-GM ECM Calibration or Power-Up Hardware that does not involve ECM reprogramming.

An example of this hardware is a propane injection system. Data only available with the 2007-2009 GMC Sierra, TopKick and 2007-2009 Chevrolet Kodiak, Silverado.

The Transmission Control Module (TCM) algorithm is implemented that records a maximum calculated input torque. This information is available via the Tech 2(R).
1. Build the vehicle with the Tech 2(R).

2. Select F3: Transmission Control Module

3. Select F1: Data Display

4. Select F0: Transmission Data

5. Max Transmission Calc Engine Torque

6. The dealership should contact the PQC, open a case to review the findings. Before a final decision on warranty coverage is made.

A CLEAR digital picture should be taken of the Tech 2(R) screen showing the transmission data, Tech2(R) VIN and reason the vehicle is currently in for service should be emailed for verification. Please copy your GM District Service Manager (DVM) in Canada (DSM) on the e-mail. GM will analyze the transmission data and respond via e-mail within 72 hours.

So let the panic ensue :P

[kp]

Was the ability to read the current CVN ever implemented?

I assume when the stock tune is loaded back in with EFILive (LBZ) the CVN should return to stock?

[LBZ]

Although that bulletin does say LLY,LBZ,LMM at the top, it only lists a procedure for checking the LMM so I ASSume that GM is only checking LMM's-which we have known for awhile. I did not know about the recorded torque input history in the TCM so maybe a guy needs to reflash the trans as well as installing a non tuned ECM.

[kp]

Although that bulletin does say LLY,LBZ,LMM at the top, it only lists a procedure for checking the LMM so I ASSume that GM is only checking LMM's-which we have known for awhile. I did not know about the recorded torque input history in the TCM so maybe a guy needs to reflash the trans as well as installing a non tuned ECM.

"2005-2007 LLY and LBZ Instructions for Confirming Calibration Verification Number (CVN)
1. Go to TIS2WEB

2. Select "Calibration Information (SPS Info)"

3. Enter VIN

4. Select "Get Cal ID"

5. Select "ECM Engine Control Module"

6. Select "Next"

7. Select "Complete History"

8. Print

9. Take the printout to the vehicle along with the Tech 2(R)

10. Plug in the Tech 2(R)

11. Go to diagnostics and build the vehicle

12. Select "Powertrain"

13. Select "Engine"

14. *Select "Engine Control Module"

15. *Select "Module ID Information" or "I/M Information System" if module ID information selection is not available.

16. *If "I/M information System" was selected in step 15, it may be necessary to select "Vehicle Information" in order to display the calibration information.

17. Compare the calibration ID and Calibration Verification Numbers (CVN) to the Calibration Verification Numbers (CVN) on the printout."

They are going to check the cal against the CVN on the older trucks according to this, not a big deal like the LMMs but if one of those segment CVNs are off on an LBZ you are screwed I guess.

It would be nice to check the CVNs without having to get a Tech 2 involved.

[LBZ]

Well F#$%!

[kp]

Well F#$%!

Same thing I thought lol, I tried a 'mileage' tune in mine last year when diesel was 5.00 a gallon, since I already had EF!live for my LS1 car I figured why not try it on the LBZ. It didnt do anything really so I put it back to stock a week or so later.

So last week I was bored, reading around this site and noticed this thread. After seeing the last post I took my truck to a friend at a local dealer and had him check the CVN numbers on all the segments and one was wrong. Even though I flashed the stock tune back in a year ago and the truck has never been to the dealer or programmed since.

The 'Engine' segment (PN 12610878) CVN was wrong. I assume since EFIlive tune says its not used you cant even change anything in it so I have no idea why it changed. The 'engine' checksum on EFIlive from my original read and the one in the truck were different as well, I have no idea why or how. I flashed the original stock tune again and now all the checksums in EFIlive are back to the same as the original read. I am going to check it again on a tech 2 soon and see if all the CVNs match. I read/flashed it with one of the first releases of EFIlive for the LBZ so maybe thats how it got messed up, I had to re-save the .tun file before it would let me flash it in with the lastest EFIlive release.

[LBZ]

I am going to check it again on a tech 2 soon and see if all the CVNs match. I read/flashed it with one of the first releases of EFIlive for the LBZ so maybe thats how it got messed up, I had to re-save the .tun file before it would let me flash it in with the lastest EFIlive release.


Can you please let us know how this turns out?

[kp]

Can you please let us know how this turns out?

Not real high priority since there is nothing wrong with the truck so it may be a while. I was hoping I was missing something and there was a way to see the CVNs in EFIlive and save me a 100 mile round trip but I guess not.

[LBZ]

No problem. Whenever you or someone else can check this it would be nice if it could be shared-no rush!

[kp]

Went there this afternoon and did the GM procedure with the tech 2 and two CVNs didnt match. The 'engine' and 'CPU' segment were both different. Downloaded a couple stock tunes from dieselplace and then some others didnt match. I then did a full reflash with the original file I took from mine and the same 2 CVNs didnt match.

To sum it up, on my LBZ putting the stock tune back in will NOT pass all the CVN segment checks on a tech 2 as described in the bulletin on post 117.

Your results may vary of course and dont use this as absolute fact, maybe someone else will try it and verify it. I didnt want the newest OS flashed in so I just left it, I'm out of warranty soon on miles anyhow but I'm sure many arent..

[LBZ]

Ok thanks for the heads up. I guess I should buy a new ECM from GM then.

[kp]

Ok thanks for the heads up. I guess I should buy a new ECM from GM then.

Like I said dont take my word for it, since I read my stock OS with the earliest LBZ software maybe something got screwed up along the way. Its funny though the one segment that was always off with no matter what I loaded in was the 'engine' one and according to EFIlive that isnt even used.

I would wait until someone else with a tech 2 and LBZ tries this before buying a new ECM.

[LBZ]

The one segment that was different was likely the one you changed for the mileage test proving that CVN counts are stored and can be recalled by GM. I think your test was perfect!

[kp]

The one segment that was different was likely the one you changed for the mileage test proving that CVN counts are stored and can be recalled by GM. I think your test was perfect!

I dont think multiple counts are stored or retrieveable like an LMM, the CVN is just a CRC, all it takes is one bit of data to be off and the number doesnt match. There was no way to retrieve any previous flashes, even with the MDI, just the segments/CVN list with the tech 2. The procedure for the LBZ is to retrieve the calbration part numbers from TIS, print them out, take the tech 2 and printout to the truck and manually check each CVN against the PN.

Easiest thing to do would be if you have an older OS just pay to have the neswest OS flashed in and dont touch it after that and swap another PCM in to tune on. At least the LBZ guys can fix it with a GM reflash I assume, the LMM guys are screwed.

[zackbennett]

Has anyone found a way to get rid of the history in the LMM's yet?! Im just curious because it is a computer.. and any computer can be figured out and beat.

[MadMaxx61]

Yes, it is known and No you will not see it added to EFI-Live.

[rcr1978]

The ECM is the easy part just buy a new $200 one and program that one, but your regen counter will be off. Now supposedly the TCM tracks a max torque input so your beat again. Everybody is just going to have to get over the fact that your warranty is gone if you tinker with it. This sucks that some have abused the system so badly that if something non tuning related is broke and you want it fixed your screwed. I guess just buy a ECM and TCM and be honest don't ruin motor's, trannies turbo's, and expect warranty

[zackbennett]

Well My dealer is pretty friendly about it, they told me that they will fix anything that would OBVIOUSLY not be caused by a tune.. IE if my AC breaks or power steering something of that nature. Although if I have a powertrain issue it may be up for debate. I guess it'll just be my excuse to upgrade to better components. I just dont feel its very fair that they can void my warrenty because I deleted the DPF. I only run stock tuning with the DPF programmed out, and there are no emissions laws here..

[LBZ]

I dont think multiple counts are stored or retrieveable like an LMM, the CVN is just a CRC, all it takes is one bit of data to be off and the number doesnt match. There was no way to retrieve any previous flashes, even with the MDI, just the segments/CVN list with the tech 2. The procedure for the LBZ is to retrieve the calbration part numbers from TIS, print them out, take the tech 2 and printout to the truck and manually check each CVN against the PN.

Easiest thing to do would be if you have an older OS just pay to have the neswest OS flashed in and dont touch it after that and swap another PCM in to tune on. At least the LBZ guys can fix it with a GM reflash I assume, the LMM guys are screwed.

Or just buy a new flashed PCM and keep tuning the one you got in until it needs to go in for warranty.:grin:

Either way, I think the egr delete pipe and boost tube I'm putting in may void my warranty anyhow!! The C&C's pistons definetly will when I build the engine!!:grin:

[L31Sleeper]

didint work on mine i put a completley new un modded ecm in my truck and it still showed all my old check sums from my previous ecm. wich meens to me the info is stored also somewhere else. ambey the tcm not sure

What gives ??

[txchevy]

Old thread.Sorry,edited!!

[L31Sleeper]

GM needs to average the warranty costs per vehicle and allow buyers to OPT out of the Warranty.