What’s the verdict on dual ECU’s for M157?




Can we do it? How about the mileage? Isn't it stored in the ECU and swapping ECU’s would cause a mileage discrepancy? Would this be a 100% safe way of avoiding detection?
I really want a tune, but not at the risk of losing the warranty, considering i still have 3 years of it.
Last edited by V-AMG; Dec 20, 2018 at 10:21 PM.
2. Nothing is 100% safe for warranty
3. If you have doubts don't do it
4. AMS cloned my ecu
5. Nothing is 100% safe
6. I have 3 years of ELw warranty left and have no worries
Last edited by PeterUbers; Dec 20, 2018 at 11:05 PM.
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So take the stock ECU, flash a tune, then revert it back to stock the file the file checksums are altered every time. Checksums are how all software files compare and detect data errors in a software file which my understanding is MB Germany (not dealer level) can detect and could explore in a warranty claim if they suspect a tuned ECU causes the engine issues
not sure what they detect with swapping.dual ECU when the original is not altered.....




First of all, thank you for the wealth of information!
Much like yourself, I am not much of a gambler when it comes to the warranty on a $100k car, so I don’t want to dive into this unless it’s a pretty safe bet. Have you swapped your stock ECU back in for dealer service? No issue with mileage discrepancy? Or something else i am overlooking? I wonder if the dealer can tell the stock ECU’s been out of the car, meaning the car ran on a different ECU.
First of all, thank you for the wealth of information!
Much like yourself, I am not much of a gambler when it comes to the warranty on a $100k car, so I don’t want to dive into this unless it’s a pretty safe bet. Have you swapped your stock ECU back in for dealer service? No issue with mileage discrepancy? Or something else i am overlooking? I wonder if the dealer can tell the stock ECU’s been out of the car, meaning the car ran on a different ECU.
yes, just had the 30k service done, stock ecu went in and no one said anything to me. I had $2000 job on the engine ... tensioners replaced ... no issues with warranty
FYI, the said dealer has α 2018 C63s with 6k miles on the clock and it has α ECU tune there now and that is exactly what Mercedes and the Mercedes master tech did to verify if the car was modded and guess what, the owner now needs to foot the bill for the repair.
I am guessing that is why tuners don’t want to mess with the TCU.
Again not trying the scare anyone, but that is how α very reliable dealer/service head with 25 plus years experience explained it to me.
What was one of the first thing I learned from this forum when I got my first AMG was. One, don’t own one without warranty and the second is you got to pay if you want to play. Not trying to be sarcastic, but I have seen it happened to a few owners to hold water.
anyone that tells you otherwise is uninformed or very much in denial.
FYI, the said dealer has α 2018 C63s with 6k miles on the clock and it has α ECU tune there now and that is exactly what Mercedes and the Mercedes master tech did to verify if the car was modded and guess what, the owner now needs to foot the bill for the repair.
I am guessing that is why tuners don’t want to mess with the TCU.
Again not trying the scare anyone, but that is how α very reliable dealer/service head with 25 plus years experience explained it to me.
What was one of the first thing I learned from this forum when I got my first AMG was. One, don’t own one without warranty and the second is you got to pay if you want to play. Not trying to be sarcastic, but I have seen it happened to a few owners to hold water.
But again I’m sure there are allot of owners who does have something go wrong with their engine and don’t have a tune.
Just a draw of the hand I guess?




FYI, the said dealer has α 2018 C63s with 6k miles on the clock and it has α ECU tune there now and that is exactly what Mercedes and the Mercedes master tech did to verify if the car was modded and guess what, the owner now needs to foot the bill for the repair.
I am guessing that is why tuners don’t want to mess with the TCU.
Again not trying the scare anyone, but that is how α very reliable dealer/service head with 25 plus years experience explained it to me.
What was one of the first thing I learned from this forum when I got my first AMG was. One, don’t own one without warranty and the second is you got to pay if you want to play. Not trying to be sarcastic, but I have seen it happened to a few owners to hold water.
My worry is if the ECU keeps mileage. Or some way for them to know the car was ran with a different ECU. If there is not, the 2nd ECU might be the loophole.
Do we have or know of anyone here who’s had an issue with a 2nd ECU and warranty?
Last edited by V-AMG; Dec 24, 2018 at 09:47 PM.







