Remap

[Graeme4130]

After talking at some length with a long established tuner about the warranty problem:
The guy was pretty certain that Audi/BMW/Porsche etc.. can find out whether a car has been tuned even if it has been flashed back without shipping the ECUs off to HQ. - They can .. allegedly... checksum the ECU via ODB and detect the tune. If it has been flashed back to normal the logs will be incorrect and whilst they may not be able to tell what tune has been put on they will probably know something has been done.

There are cases of people saying that they have flashed back but have still had their warranties voided.

http://oppositelock.kinja.com/help-audi ... 1467844528

Conversely I have had more than one dealer telling me to just go ahead and tune the car I've just bought because "everyone" does it . This forum at least isn't full of people saying their warranty has been voided by Audi and there must be a pretty size-able number here who have tuned their cars!

As W8PMC says - a lot of tuners warranty the tune. If this is insurance backed then you are probably ok..

Personally... I generally avoid tuning my cars, just not worth it imo..

http://www.autoblog.com/2010/12/28/5-th ... -warranty/

http://www.reddit.com/r/GolfGTI/comment ... _warranty/

The ECU will record and store any changes, so even if you put it back to standard, it'll still show that there's been an 'unauthorised' change to the software at some point, but obviously won't be able to tell what the changes are. This check, I believe, can be done at UK dealer level
My understanding is that Audi uk Warranty dept, who the dealer have to seek approval from to do any warranty work, are increasingly asking for the ECU's being checked by the dealer and a report submitted with any claim
As is always the case with these things, if you give them a chance to wriggle out of paying for any warranty work, they'll take it, and I can't imagine engine related claims as a result of increased boost are cheap.
But then on the flip side, it's easy work for the dealer, so if you're relationship with them is good...

[W8PMC]

After talking at some length with a long established tuner about the warranty problem:
The guy was pretty certain that Audi/BMW/Porsche etc.. can find out whether a car has been tuned even if it has been flashed back without shipping the ECUs off to HQ. - They can .. allegedly... checksum the ECU via ODB and detect the tune. If it has been flashed back to normal the logs will be incorrect and whilst they may not be able to tell what tune has been put on they will probably know something has been done.

There are cases of people saying that they have flashed back but have still had their warranties voided.

http://oppositelock.kinja.com/help-audi ... 1467844528

Conversely I have had more than one dealer telling me to just go ahead and tune the car I've just bought because "everyone" does it . This forum at least isn't full of people saying their warranty has been voided by Audi and there must be a pretty size-able number here who have tuned their cars!

As W8PMC says - a lot of tuners warranty the tune. If this is insurance backed then you are probably ok..

Personally... I generally avoid tuning my cars, just not worth it imo..

http://www.autoblog.com/2010/12/28/5-th ... -warranty/

http://www.reddit.com/r/GolfGTI/comment ... _warranty/

I'm not in a position to speak for other tuners, as my experiences & loyalty are with DMS who i've used for many years & on a variety of cars. They do NOT flash the ECU which i agree is a little easier to detect (although still not at a dealer level). Totally agree that a reflash is a touch more risky & hence why piggyback Tuning Boxes have started to become more popular, using the benefit of it being plug & play that can be removed when needing to visit the dealer, however you're then losing the benefit of having a custom tune & believe me that some cars are wildly different stock so banging an off the shelf tune on them is perhaps not the best tuning option.

Who was the Tuner that said a dealer can detect a tune?

[BFT - John]

To be clear for all your guys. If you tune the car, even in boot mode (Opening the ECU and flashing in directly) the MED17 ecu will be spotted by Audi Germany. Same with OBD flashing which is available on these.

They will flag it as TD1 warranty code when they do the SWM check.

Note the keyword being Audi Germany. Your dealer & Audi UK have no hardware to detect a decent remap & TBH, you'd have to have a shitty relationship with your dealer for them to remove the ECU's & ship them to Germany just to get one over on you.

If (& believe me it's a monumental if) this did ever happen, assuming you've used a reputable tuner, you'd be covered by their warranty so all this warranty scaremongering is pointless as in the worst case you'd be covered by the tuners warranty & the best case by your Audi/dealer warranty

I can guarantee you that you are 100% wrong sorry!

The dealer has the capability via doing a check which is requested by the factory. Audi UK are controlled by Audi Germany 'the factory!' via the CVN.

They will be able to tell you at what mileage the car was tuned, and put back to standard. Then retuned if required.

Doesn't matter if it has been done in Tricore boot mode (ECU out) or flashed on the bench. IF it goes to Audi with a tune on it, they will spot it if the car is in for warranty work.

[W8PMC]

To be clear for all your guys. If you tune the car, even in boot mode (Opening the ECU and flashing in directly) the MED17 ecu will be spotted by Audi Germany. Same with OBD flashing which is available on these.

They will flag it as TD1 warranty code when they do the SWM check.

Note the keyword being Audi Germany. Your dealer & Audi UK have no hardware to detect a decent remap & TBH, you'd have to have a shitty relationship with your dealer for them to remove the ECU's & ship them to Germany just to get one over on you.

If (& believe me it's a monumental if) this did ever happen, assuming you've used a reputable tuner, you'd be covered by their warranty so all this warranty scaremongering is pointless as in the worst case you'd be covered by the tuners warranty & the best case by your Audi/dealer warranty

I can guarantee you that you are 100% wrong sorry!

The dealer has the capability via doing a check which is requested by the factory. Audi UK are controlled by Audi Germany 'the factory!' via the CVN.

They will be able to tell you at what mileage the car was tuned, and put back to standard. Then retuned if required.

Doesn't matter if it has been done in Tricore boot mode (ECU out) or flashed on the bench. IF it goes to Audi with a tune on it, they will spot it if the car is in for warranty work.

Likewise.

If Audi UK request an ECU Analysis then they'd need removing & sending to either Audi in Germany or the ECU OEM Mfctr (pretty sure it's Bosch but i could be wrong). Some data from the ECU's can be extracted by the dealer on their simple Diagnostics machine, but what lines of code have/have not have been rewritten isn't visible. I do recall to support your point that reflashes are possibly visible at Dealer level, but if not then certainly Audi UK's bigger puter.

As above, i can't speak for other tunes & what footprints they leave behind so i'll caveat by saying some may be far more obvious than others. As also said, if using a reputable tuner this debate becomes pointless as you have a 2nd line of coverage should it ever be needed.

[DragonRR]

After talking at some length with a long established tuner about the warranty problem:
The guy was pretty certain that Audi/BMW/Porsche etc.. can find out whether a car has been tuned even if it has been flashed back without shipping the ECUs off to HQ. - They can .. allegedly... checksum the ECU via ODB and detect the tune. If it has been flashed back to normal the logs will be incorrect and whilst they may not be able to tell what tune has been put on they will probably know something has been done.

There are cases of people saying that they have flashed back but have still had their warranties voided.

http://oppositelock.kinja.com/help-audi ... 1467844528

Conversely I have had more than one dealer telling me to just go ahead and tune the car I've just bought because "everyone" does it . This forum at least isn't full of people saying their warranty has been voided by Audi and there must be a pretty size-able number here who have tuned their cars!

As W8PMC says - a lot of tuners warranty the tune. If this is insurance backed then you are probably ok..

Personally... I generally avoid tuning my cars, just not worth it imo..

http://www.autoblog.com/2010/12/28/5-th ... -warranty/

http://www.reddit.com/r/GolfGTI/comment ... _warranty/

I'm not in a position to speak for other tuners, as my experiences & loyalty are with DMS who i've used for many years & on a variety of cars. They do NOT flash the ECU which i agree is a little easier to detect (although still not at a dealer level). Totally agree that a reflash is a touch more risky & hence why piggyback Tuning Boxes have started to become more popular, using the benefit of it being plug & play that can be removed when needing to visit the dealer, however you're then losing the benefit of having a custom tune & believe me that some cars are wildly different stock so banging an off the shelf tune on them is perhaps not the best tuning option.

Who was the Tuner that said a dealer can detect a tune?

I've done quite a lot of recent investigation with the 911 so I'm really referring to that in my comments. The best tune for the 911 seems to be by GIAC who, according to the UK tuner, take the tune from the car and provide a custom ECU flash for it using the existing data. I was told that it was likely that the modification to the ECU could be detected fairly easily if it was left on. If the ECU was reset to default then it was "likely" that "they" could detect that it had been reset but not what had actually been done.

Logically I am certain that it would be a trivial matter to check that the data/code on the ECU is at factory default settings and there is no technical reason why this couldn't be exposed via ODB. Whether Audi/BMW etc.. actually do this.. I don't know. When I picked up my 911 last year there was a fault and I was told the Porsche Germany were connected into the car and running diagnostics.... This doesn't mean that they can check the contents of the ECU and compare but I wouldn't mind having a small bet!

The same tuner, and others (including you) have suggested that a piggy back style tune is much harder to detect if it is removed because the ECU doesn't get flashed at all and is handed faked readings and/or readings it sends out are adjusted on the fly. However the tuner did say that piggy back tunes are less "reliable" and have a greater chance of causing problems because not all data may be captured and adjusted correctly and as you quite correctly state - they are off the shelf and not customised for the particular vehicle.

Just as a footnote on this general subject - I don't know whether this applies to the RS6 but on the 911 991TTS an exhaust change does nothing for performance because, after a couple of weeks, the 991 variants adapt:

http://www.europipe.be/exhausts.html

[W8PMC]

Totally agree as regards the Piggy Back tunes & the main reason i'd steer well clear unless it was on a 320d or the like.

Like you i can't speak for every marque/brand/tune, but have had many & never encountered any warranty issues. That said perhaps i've just been lucky but worth noting i've had some high value claims on modified vehicles.

I know how my current tune is carried out, hence my level of confidence as it's ECU out & lines of code rewritten. The Software would need comparing line by line to see any change & that isn't something that can be done by a dealer or even in BMW's case in the UK. Also if it's reset, it's the lines of code that are changed back (the stock code is of course held on file) so no reflash & why that too is not noticeable.

I'll caveat that if any Manufacturer really wanted to get one over on a customer then i'm sure they could, but in reality it's extremely rare & as i've said if you use a reputable tuner you'd be covered by their warranty should the unthinkable happen. Also worth noting that if using a quality Custom tune, the chances of any major mechanical issues is extremely rare.

[bam_bam]

The Software would need comparing line by line to see any change & that isn't something that can be done by a dealer or even in BMW's case in the UK. Also if it's reset, it's the lines of code that are changed back (the stock code is of course held on file) so no reflash & why that too is not noticeable.

Wrong. "The Software" does not need to compare code line by line, this is retarded. Programatically a tool is deployed to hash the file/code container, simple as that. The tool would have a known hash set of OEM ECU files, any metadata change such as a create date, modified date or a single character of 'code' is out, the hash will not match, thus denoting a change to the file in question. This is simple statistics and there'd be known hashes for all files created for ECUs. It's how software development works (well, good software development).

[W8PMC]

The Software would need comparing line by line to see any change & that isn't something that can be done by a dealer or even in BMW's case in the UK. Also if it's reset, it's the lines of code that are changed back (the stock code is of course held on file) so no reflash & why that too is not noticeable.

Wrong. "The Software" does not need to compare code line by line, this is retarded. Programatically a tool is deployed to hash the file/code container, simple as that. The tool would have a known hash set of OEM ECU files, any metadata change such as a create date, modified date or a single character of 'code' is out, the hash will not match, thus denoting a change to the file in question. This is simple statistics and there'd be known hashes for all files created for ECUs. It's how software development works (well, good software development).

My explanation was simplified as unless i'm missing a trick Audi dealers (or any dealers for that matter) are not known to be awash with Software Developers. Yes when comparing code you'd of course not make any comparisons line by line, as if this was the case new software would take years to come to market & fault resolution months, however a dealers diagnostic machine does not have such capability & would therefore be looking for obvious differences such as a flash count which in the example i made would not be present.

Unless things have moved on significantly in the last few weeks, a dealers capacity to spot a change to one/several lines of code does not exist & never has, this capability i've been told only resides with (as regards vehicles). If i've been misinformed then fair enough.

[bam_bam]

My explanation was simplified as unless i'm missing a trick Audi dealers (or any dealers for that matter) are not known to be awash with Software Developers.

Wait, what?
But the software and diagnostics tools they use were created/made by software developers. Bosch, Audi AG, 3rd parties, contractors etc etc.
Your comment is like me saying "oh you use a Wintel computer but you don't know how to operate the C# 2.0 Command Line Compiler". No one is accusing an Audi stealer of being a software developer, but the people that made the tools that a stealer has at their disposal, clearly were/are. When an ECU goes live it will be distributed and stored with a hash number or hash file. This hash would be entered into a 'known ECU' database and can be used to perform checks against any ECU, if the checksum fails, the ECU in question is modified.

Yes when comparing code you'd of course not make any comparisons line by line.

Then why did you 'say' this: "The Software would need comparing line by line to see any change & that isn't something that can be done by a dealer or even in BMW's case in the UK"
It's very confusing logic to 'say' one thing then 'say' the opposite in the next post.

...however a dealers diagnostic machine does not have such capability & would therefore be looking for obvious differences such as a flash count which in the example i made would not be present.

The latest VAG/Bosch units don't use flashcounts from what I know, they create a flag when the hash/checksum fails. Most tuners just overwrite this flag but a simple hash of the bin/ECU file would show the ECU as modified from OEM.

Unless things have moved on significantly in the last few weeks, a dealers capacity to spot a change to one/several lines of code does not exist & never has, this capability i've been told only resides with (as regards vehicles). If i've been misinformed then fair enough.

The Internet's currency is opinion, misinformation just cheapens the whole place up, don't hide behind it.

[W8PMC]

My explanation was simplified as unless i'm missing a trick Audi dealers (or any dealers for that matter) are not known to be awash with Software Developers.

Wait, what?
But the software and diagnostics tools they use were created/made by software developers. Bosch, Audi AG, 3rd parties, contractors etc etc.
Your comment is like me saying "oh you use a Wintel computer but you don't know how to operate the C# 2.0 Command Line Compiler". No one is accusing an Audi stealer of being a software developer, but the people that made the tools that a stealer has at their disposal, clearly were/are. When an ECU goes live it will be distributed and stored with a hash number or hash file. This hash would be entered into a 'known ECU' database and can be used to perform checks against any ECU, if the checksum fails, the ECU in question is modified.

Yes when comparing code you'd of course not make any comparisons line by line.

Then why did you 'say' this: "The Software would need comparing line by line to see any change & that isn't something that can be done by a dealer or even in BMW's case in the UK"
It's very confusing logic to 'say' one thing then 'say' the opposite in the next post.

...however a dealers diagnostic machine does not have such capability & would therefore be looking for obvious differences such as a flash count which in the example i made would not be present.

The latest VAG/Bosch units don't use flashcounts from what I know, they create a flag when the hash/checksum fails. Most tuners just overwrite this flag but a simple hash of the bin/ECU file would show the ECU as modified from OEM.

Unless things have moved on significantly in the last few weeks, a dealers capacity to spot a change to one/several lines of code does not exist & never has, this capability i've been told only resides with (as regards vehicles). If i've been misinformed then fair enough.

The Internet's currency is opinion, misinformation just cheapens the whole place up, don't hide behind it.

It's really very simple & somewhat obvious being two totally different scenarios. YES to test code (generic) you'd of course not do this line by line. NO to find a small number of changes to a few lines of code on a cars ECU would need a different approach that as far as i'm aware, only the OEM ECU Mfctr could access.

Perhaps line by line is not the greatest description i could have used, but i tended to think i wasn't trying to satisfy a developer, merely stating what is/isn't noticeable by a dealer on a bench coded ECU.

[RossDagley]

It's really very simple & somewhat obvious being two totally different scenarios. YES to test code (generic) you'd of course not do this line by line. NO to find a small number of changes to a few lines of code on a cars ECU would need a different approach that as far as i'm aware, only the OEM ECU Mfctr could access.

Perhaps line by line is not the greatest description i could have used, but i tended to think i wasn't trying to satisfy a developer, merely stating what is/isn't noticeable by a dealer on a bench coded ECU.

When the whole ECU firmware is coded, a checksum is taken of the completed file. Once done, that checksum hash is stored as a known ECU hash in a database somewhere - in this case, perhaps "2014 RS6 Avant" or something. I'm simplifying this aspect. the bottom line is it's whole file is checksummed and the known hash stored. This has obviously is the same for all identical model cars ECU's.

If ANY single byte anywhere in the file at all, is changed, the checksum changes. When the car is in for a service/warranty/whatever, all that is required is for the dealer to read the checksum from the ECU and compare it to the list of known Audi ECU checksums. They won't match.

They can't read the ECU code itself, and nor do they need to - they simply know something has changed.

Job done.

[W8PMC]

It's really very simple & somewhat obvious being two totally different scenarios. YES to test code (generic) you'd of course not do this line by line. NO to find a small number of changes to a few lines of code on a cars ECU would need a different approach that as far as i'm aware, only the OEM ECU Mfctr could access.

Perhaps line by line is not the greatest description i could have used, but i tended to think i wasn't trying to satisfy a developer, merely stating what is/isn't noticeable by a dealer on a bench coded ECU.

When the whole ECU firmware is coded, a checksum is taken of the completed file. Once done, that checksum hash is stored as a known ECU hash in a database somewhere - in this case, perhaps "2014 RS6 Avant" or something. I'm simplifying this aspect. the bottom line is it's whole file is checksummed and the known hash stored. This has obviously is the same for all identical model cars ECU's.

If ANY single byte anywhere in the file at all, is changed, the checksum changes. When the car is in for a service/warranty/whatever, all that is required is for the dealer to read the checksum from the ECU and compare it to the list of known Audi ECU checksums. They won't match.

They can't read the ECU code itself, and nor do they need to - they simply know something has changed.

Job done.

Great & clear explanation, thank you. I was aware of some of these points but certainly not all.

Does this though in the real world equate to any UK Audi dealer being able to take said approach & spot a change to the ECU?

Going deeper, the code can be changed for several reasons & not all related to a tune, such as a software update which many cars nowadays get fairly frequently, faults codes & certain other data log parameters that are written. This being the case, surely a 'somethings changed' flag is to be expected & would not lead a dealer or Audi to question it? Are all changes logged through the life of the car?

I ask this as my recent experiences are with BMW & although i'd never follow the belief that any tune is undetectable, i am assured that under all but the most extreme investigations it won't be seen & as a safety net mentioned above, a reputable tuner would have this covered under their warranty.

I'm not a Software Developer & neither am i an expert in tuning, but i do trust the various sources i hear the above from.

[bam_bam]

Does this though in the real world equate to any UK Audi dealer being able to take said approach & spot a change to the ECU?

It'd be pretty easy, whether a grease monkey can be bothered to follow a protocol is a different story. I also think there are a load of other powers at play. For example, when using Camberely Audi for Mondial warranty work, they were more than happy to pull the engine for a failed 20p seal but when asked to investigate the beginnings of a torque converter failure, they started to question whether the car had a map. It did. They found it did have a map and they advised I take the matter no further with them, this, after racking up over £3.5k in labour... and 20p in parts. I think certain stealers picker their battles and they know what type of warranty work will come under more scrutiny.

Going deeper, the code can be changed for several reasons & not all related to a tune, such as a software update which many cars nowadays get fairly frequently, faults codes & certain other data log parameters that are written. This being the case, surely a 'somethings changed' flag is to be expected & would not lead a dealer or Audi to question it? Are all changes logged through the life of the car?

Faults and logs would not be stored in the ECU base tune, these values should remain read only. Same with updates, I'd assume it'd be an overwrite, either partial or full, in which case a known hash would be distributed with the update file AND a precalculated hash for the whole file once updated.

Interesting topic though. There's a guy over on the C5 forum that plays around with the files a lot. I'd like to know his take.

[W8PMC]

Does this though in the real world equate to any UK Audi dealer being able to take said approach & spot a change to the ECU?

It'd be pretty easy, whether a grease monkey can be bothered to follow a protocol is a different story. I also think there are a load of other powers at play. For example, when using Camberely Audi for Mondial warranty work, they were more than happy to pull the engine for a failed 20p seal but when asked to investigate the beginnings of a torque converter failure, they started to question whether the car had a map. It did. They found it did have a map and they advised I take the matter no further with them, this, after racking up over £3.5k in labour... and 20p in parts. I think certain stealers picker their battles and they know what type of warranty work will come under more scrutiny.

Going deeper, the code can be changed for several reasons & not all related to a tune, such as a software update which many cars nowadays get fairly frequently, faults codes & certain other data log parameters that are written. This being the case, surely a 'somethings changed' flag is to be expected & would not lead a dealer or Audi to question it? Are all changes logged through the life of the car?

Faults and logs would not be stored in the ECU base tune, these values should remain read only. Same with updates, I'd assume it'd be an overwrite, either partial or full, in which case a known hash would be distributed with the update file AND a precalculated hash for the whole file once updated.

Interesting topic though. There's a guy over on the C5 forum that plays around with the files a lot. I'd like to know his take.

I'd be interested too. I know from previous experience that BMW Software updates wiped the amended code i had on the car & why the Tuner in question offered to rewrite the code to the ECU under just such circumstances. No idea if Audi &/or other marques adopt the same format for Software Updates, but i'd presume they do.

Fault codes & logs i'm not so sure as was told by Nissan that this data is held on the/an ECU in the R35 GT-R & is easily pulled off the car for Warranty issues etc. but the files are not read by the dealer, only by Nissan GB.

Totally agree on whether or not a dealer would bother & i'd guess only a major engine/transmission failure/fault would attract any real scrutiny as it would still need proving or at the very least assuming a tune had caused the fault.

[BFT - John]

This is the CVN number which is stored in the serial eeprom of the ECU. If you write whether it be a stock file or modified, it will change the CVN number.

This number is what the dealership computer can see. You do not need to download the IROM (where the maps are stored) and compare against ori to see this. All they can see is the original file or 'a' modified file has been tuned.

Any software update will overwrite the ecu information and lose the map so to speak.

BMW have been able to spot an ECU remap by OBD, or BDM/Tricore mode since 2009 (Possibly earlier).

I agree it has to be spotted to be voided, but modern day things have changed. Doesn't mean there is a way around them, however once a TD1 stamp is on the car, it cannot be removed.

Likewise.

Well agree to disagree but willing to wager highly on it!