ECU Upgrades-Detectable By Dealers?
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09 Steel Gray C63
ECU Upgrades-Detectable By Dealers?
I have a CPO car and don't want to risk the warranty. Can they tell if you have an ECU mod? Also, would they reflash the ECU during a service event thus wiping out the pricey mod?
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C63 AMG
They wont just reflash your ECU because you took it for a service. Its a 2-3 hour job at the dealer to flash an ECU and they don't look at them unless they are very suspicious or you gave them a hint or reason to look at it.
If you are worried about warranty, get a secondary ECU for your tune and keep the stock unit.
If you are worried about warranty, get a secondary ECU for your tune and keep the stock unit.
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C63 & Mustang Mach1(s)
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C63 AMG
Ya but how can they prove that you actually went and got a tune and used it???
All you have to say is that you bought the ECU, had second thoughts and its been sitting at home ever since.
Or take it to another dealer who you don't regularly go to.
I am doing his exact process and have never had any problems. Just had the car in there for warranty work and its going back tomorrow to have a left bank lean and cam tensioner repaired tomorrow.
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AMG GLC63. Audi R8
Ya but how can they prove that you actually went and got a tune and used it???
All you have to say is that you bought the ECU, had second thoughts and its been sitting at home ever since.
Or take it to another dealer who you don't regularly go to.
I am doing his exact process and have never had any problems. Just had the car in there for warranty work and its going back tomorrow to have a left bank lean and cam tensioner repaired tomorrow.
All you have to say is that you bought the ECU, had second thoughts and its been sitting at home ever since.
Or take it to another dealer who you don't regularly go to.
I am doing his exact process and have never had any problems. Just had the car in there for warranty work and its going back tomorrow to have a left bank lean and cam tensioner repaired tomorrow.
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C63 AMG
ECU cost around 2k then about 300 bucks to program it to the car. You can honestly swap them in under 2minutes with zero tools, they pop right out.
Once my warranty is done I will inquire if its possible to re-write over it for a new car as I will have no need for 2 ECUs then.. (Warranty up in about 7 months)
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2008 CLK 550
Renntech reflash and warranty - 2012
January 2012 - Renntech were very helpful and confirmed that you may have only ONE ECU per vehicle.
They did not elaborate, although I speculate the alarm system is encoded for a specific vehicle/ECU match.
If the dealership flashes the modified ECU, Renntech WILL reflash at no charge
I can not post with any certainty that ECU flashes will not be logged and revealed in a subsequent diagnostic at the dealership.
There are conflicting opinions on that VERY important topic.
The law prevents manufacturers from avoiding warranty claims at their discretion
UNLESS they can demonstrate that any action or inaction by the customer is directly attributable to the specific component failure.
They did not elaborate, although I speculate the alarm system is encoded for a specific vehicle/ECU match.
If the dealership flashes the modified ECU, Renntech WILL reflash at no charge
I can not post with any certainty that ECU flashes will not be logged and revealed in a subsequent diagnostic at the dealership.
There are conflicting opinions on that VERY important topic.
The law prevents manufacturers from avoiding warranty claims at their discretion
UNLESS they can demonstrate that any action or inaction by the customer is directly attributable to the specific component failure.
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2013 E63 AMG
January 2012 - Renntech were very helpful and confirmed that you may have only ONE ECU per vehicle.
They did not elaborate, although I speculate the alarm system is encoded for a specific vehicle/ECU match.
If the dealership flashes the modified ECU, Renntech WILL reflash at no charge
I can not post with any certainty that ECU flashes will not be logged and revealed in a subsequent diagnostic at the dealership.
There are conflicting opinions on that VERY important topic.
The law prevents manufacturers from avoiding warranty claims at their discretion
UNLESS they can demonstrate that any action or inaction by the customer is directly attributable to the specific component failure.
They did not elaborate, although I speculate the alarm system is encoded for a specific vehicle/ECU match.
If the dealership flashes the modified ECU, Renntech WILL reflash at no charge
I can not post with any certainty that ECU flashes will not be logged and revealed in a subsequent diagnostic at the dealership.
There are conflicting opinions on that VERY important topic.
The law prevents manufacturers from avoiding warranty claims at their discretion
UNLESS they can demonstrate that any action or inaction by the customer is directly attributable to the specific component failure.
Maybe you can elaborate on Renntech's official comments on this issue.
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home the point
+1, the warranty claims can't be rejected on the basis of any modification to the manufactured standards; burden of proof is on the shop/manufacturer.
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2017 Mini Cooper S Clubman ALL4 - British Racing Green
Since the ECU controls all aspects of teh drive train, if you have a problem with the engine or transmission, they can, and will void any warranty work, if your window or radio breaks, that would still be covered under warranty.
As others have said, find a dealer with a relationship with a tuner, and utilize that relationship.
As others have said, find a dealer with a relationship with a tuner, and utilize that relationship.
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home the point
Since the ECU controls all aspects of teh drive train, if you have a problem with the engine or transmission, they can, and will void any warranty work, if your window or radio breaks, that would still be covered under warranty.
As others have said, find a dealer with a relationship with a tuner, and utilize that relationship.
As others have said, find a dealer with a relationship with a tuner, and utilize that relationship.
Google "FTC Magnuson-Moss Warranty Act" for more info.
Last edited by cptdaz; Jan 11, 2012 at 01:47 PM.
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From: NA
Yes
Simple answers:
YES they can see if you have a tune.
YES they can reflash over your tune.
YES if the dealer does reflash over your tune for a new software update or some other reason, you can, under most tuners policies, send the ECU back for a free reflash.
NO the dealer cannot void your entire warranty from an ECU tune. they would have to prove that the failed part was directly due to your modification. If your door lock stops working, they will fix it. If they dont, escalate to MB USA. If you throw a CEL, expect them to not honor your warranty if they know it's tuned.
YES some dealers are modification friendly. Some sell Renntech parts for example and will warranty them. Most however do not.
YES many SA's are mod friendly regardless of their dealerships' position.
YES most people just get tuned and go to the dealer like there is no tune at all when issues pop up, the dealer doesnt think to check for a tune to blame the problem on, they just fix the problem and move on.
NO most people dont buy 2 ECU's and swap back and forth. Certainly an option but not realistic for most.
YES they can see if you have a tune.
YES they can reflash over your tune.
YES if the dealer does reflash over your tune for a new software update or some other reason, you can, under most tuners policies, send the ECU back for a free reflash.
NO the dealer cannot void your entire warranty from an ECU tune. they would have to prove that the failed part was directly due to your modification. If your door lock stops working, they will fix it. If they dont, escalate to MB USA. If you throw a CEL, expect them to not honor your warranty if they know it's tuned.
YES some dealers are modification friendly. Some sell Renntech parts for example and will warranty them. Most however do not.
YES many SA's are mod friendly regardless of their dealerships' position.
YES most people just get tuned and go to the dealer like there is no tune at all when issues pop up, the dealer doesnt think to check for a tune to blame the problem on, they just fix the problem and move on.
NO most people dont buy 2 ECU's and swap back and forth. Certainly an option but not realistic for most.
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From: Colorado
2021 E63 S Sedan
They can see your tune, but they have to look for it. They won't see it on normal service A or service B scheduled maintenance visits. Best advice though is to develop a good relationship with the service manager and discuss a tune openly with them. Mine was Kleemen tuned and my service manager completely supported me. It helped that he new of Cory (at Kleeman) and the safety of the Kleeman tune.
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From: Melbourne
(a)'12 C63 P/P, LSD, 19" m/spoke,comfort pack. (b)Astra SRI.
Well, of course you don't have to tell your Dealer that you've had an ECU upgrade, & having had no experience to date with what is/is not done at service time, the dealer may/may not become aware of anything.....but, then, if for any reason, they reflash your ECU, then you would lose your tune would you not.
As far as warranty is concerned, if a serious mechanical issue occured, which could in any way be traced back to the ECU via increased power/torque etc, whether it really was, or was not, caused by the upgrade, I reckon you could have a problem.
Cheers, Pickles.
As far as warranty is concerned, if a serious mechanical issue occured, which could in any way be traced back to the ECU via increased power/torque etc, whether it really was, or was not, caused by the upgrade, I reckon you could have a problem.
Cheers, Pickles.
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2008 CLK 550
Simple answers:
YES they can see if you have a tune.
YES they can reflash over your tune.
YES if the dealer does reflash over your tune for a new software update or some other reason, you can, under most tuners policies, send the ECU back for a free reflash.
NO the dealer cannot void your entire warranty from an ECU tune. they would have to prove that the failed part was directly due to your modification. If your door lock stops working, they will fix it. If they dont, escalate to MB USA. If you throw a CEL, expect them to not honor your warranty if they know it's tuned.
YES some dealers are modification friendly. Some sell Renntech parts for example and will warranty them. Most however do not.
YES many SA's are mod friendly regardless of their dealerships' position.
YES most people just get tuned and go to the dealer like there is no tune at all when issues pop up, the dealer doesnt think to check for a tune to blame the problem on, they just fix the problem and move on.
NO most people dont buy 2 ECU's and swap back and forth. Certainly an option but not realistic for most.
YES they can see if you have a tune.
YES they can reflash over your tune.
YES if the dealer does reflash over your tune for a new software update or some other reason, you can, under most tuners policies, send the ECU back for a free reflash.
NO the dealer cannot void your entire warranty from an ECU tune. they would have to prove that the failed part was directly due to your modification. If your door lock stops working, they will fix it. If they dont, escalate to MB USA. If you throw a CEL, expect them to not honor your warranty if they know it's tuned.
YES some dealers are modification friendly. Some sell Renntech parts for example and will warranty them. Most however do not.
YES many SA's are mod friendly regardless of their dealerships' position.
YES most people just get tuned and go to the dealer like there is no tune at all when issues pop up, the dealer doesnt think to check for a tune to blame the problem on, they just fix the problem and move on.
NO most people dont buy 2 ECU's and swap back and forth. Certainly an option but not realistic for most.
Thanks for clearing up the doubt about whether or not the dealer can see the reflash.
The onus is on the dealer to demonstrate a customer-installed modification caused the failure of a particular component, in rejecting a warranty claim.
I imagine the dealer could successfully rely upon the argument that the customer's actions resulted in physical stress being applied, outside the normal operating parameters of the engine/drivetrain.
Since the reflash claims to provide only 20 hp more at the flywheel, whether this would constitute unacceptable additional physical stress is open to debate.
Too much uncertainty and too much cash at stake, to take a chance, methinks.
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2006 CLS500 - Iridium Silver w/ AMG Sportline
I tell them when I drop off, do NOT reflash without my permission. I have a tune. They don't care nor have them denied me warranty work. And, if they refuse at any point, they have to prove the damage was specifically caused by the tune, something I'm not worried about in the slightest.
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C63 AMG
Wowzers a lot of crazy talk in this thread.
I have TWO ECU's YES that is possible and IMO the best way to do it! Then you always have your UNTOUCHED STOCK ECU you can pop in and get warranty work done!! I got my second ECU tuned.. How the hell do they know I am actually using the second ECU? All they know is the car is stock and its needs warranty work so fix it.
NO, they can not tell you have a tune!!! My GOOD GOOD friend is a tech and works on my car at the dealer, his tools gave him no indication of a tune being on the car. Perhaps they can send it to Germany or something and do some in depth testing, but he has found no way to see a tune at the local dealer!!
I dunno where you guys take your cars but people HAVE been refused warranty work because of modifications to the car!! One guys engine went KA BOOM and he had an exhaust.. He had to buy a whole new complete stock exhaust, have it installed so the car was stock before they would fix anything. So YES they can deny whatever the hell they want.. Unless you want to waste time taking them to court LOL.
I have TWO ECU's YES that is possible and IMO the best way to do it! Then you always have your UNTOUCHED STOCK ECU you can pop in and get warranty work done!! I got my second ECU tuned.. How the hell do they know I am actually using the second ECU? All they know is the car is stock and its needs warranty work so fix it.
NO, they can not tell you have a tune!!! My GOOD GOOD friend is a tech and works on my car at the dealer, his tools gave him no indication of a tune being on the car. Perhaps they can send it to Germany or something and do some in depth testing, but he has found no way to see a tune at the local dealer!!
I dunno where you guys take your cars but people HAVE been refused warranty work because of modifications to the car!! One guys engine went KA BOOM and he had an exhaust.. He had to buy a whole new complete stock exhaust, have it installed so the car was stock before they would fix anything. So YES they can deny whatever the hell they want.. Unless you want to waste time taking them to court LOL.
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From: NA
Yes
Rory...
Thanks for clearing up the doubt about whether or not the dealer can see the reflash.
The onus is on the dealer to demonstrate a customer-installed modification caused the failure of a particular component, in rejecting a warranty claim.
I imagine the dealer could successfully rely upon the argument that the customer's actions resulted in physical stress being applied, outside the normal operating parameters of the engine/drivetrain.
Since the reflash claims to provide only 20 hp more at the flywheel, whether this would constitute unacceptable additional physical stress is open to debate.
Too much uncertainty and too much cash at stake, to take a chance, methinks.
Thanks for clearing up the doubt about whether or not the dealer can see the reflash.
The onus is on the dealer to demonstrate a customer-installed modification caused the failure of a particular component, in rejecting a warranty claim.
I imagine the dealer could successfully rely upon the argument that the customer's actions resulted in physical stress being applied, outside the normal operating parameters of the engine/drivetrain.
Since the reflash claims to provide only 20 hp more at the flywheel, whether this would constitute unacceptable additional physical stress is open to debate.
Too much uncertainty and too much cash at stake, to take a chance, methinks.
BTW - Merc63 what you described is fraud, and if the dealer found out, your buddy would be on the hook for every single penny if not more, unless he could prove that the exhaust had nothing to do with it (which it most certainly didnt, but the quote above describes exactly how they would approach it and he would be screwed). That hassle of secretly swapping stuff out is just not worth it to some of us. Not saying it isnt for you, just speaking on my own feelings.
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2008 CLK 550
Thanx Merc...
See how difficult it is to reach a conclusion when reading unequivocal statements - given in good faith - which directly contradict one another
Today, I specifically asked:
Bob Brady
Senior Product Specialist
Special Projects
RENNtech
(he is a very helpful guy)
whether or not I could keep my stock ECU on the shelf and have them flash a second ECU...
for the very reason YOU mentioned.
___________________________________
Bob replied this could NOT be done - quote:
"I wish it was that easy.
But you can only have one ECU that will work in your car, so we have to
program the one that you currently have."
____________________________________
The other question is the all-important "can the dealership discern if the ECU has been reflashed"...?
My research has revealed contradictory opinions on that yes/no question.
I am also confident that MB will flatly refuse to pick up the tab for warranty claim on a broken, ECU-modified vehicle...
although the customer is welcome to pay a lawyer and take their chances in court.
Thanx again.
See how difficult it is to reach a conclusion when reading unequivocal statements - given in good faith - which directly contradict one another
Today, I specifically asked:
Bob Brady
Senior Product Specialist
Special Projects
RENNtech
(he is a very helpful guy)
whether or not I could keep my stock ECU on the shelf and have them flash a second ECU...
for the very reason YOU mentioned.
___________________________________
Bob replied this could NOT be done - quote:
"I wish it was that easy.
But you can only have one ECU that will work in your car, so we have to
program the one that you currently have."
____________________________________
The other question is the all-important "can the dealership discern if the ECU has been reflashed"...?
My research has revealed contradictory opinions on that yes/no question.
I am also confident that MB will flatly refuse to pick up the tab for warranty claim on a broken, ECU-modified vehicle...
although the customer is welcome to pay a lawyer and take their chances in court.
Thanx again.
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E55, SL63, ML550
Well no, it takes about 11 min. to reflash a ME control unit. Granted, this will not be done for no reason. It can be obvious if the unit has been opened up, and modified. But, like others said, if there is no reason to look then who cares--at my dealer we have installed many "tuned" units. My coworker who has a C63 just had his done by Kleeman. I can say, he went from running a best of 12.7 in the 1/4 to 12.3, matching my stock e55 side by side. (although my best run was 12.2 haha. But basically we run side by side now. Woke his car up.
They wont just reflash your ECU because you took it for a service. Its a 2-3 hour job at the dealer to flash an ECU and they don't look at them unless they are very suspicious or you gave them a hint or reason to look at it.
If you are worried about warranty, get a secondary ECU for your tune and keep the stock unit.
If you are worried about warranty, get a secondary ECU for your tune and keep the stock unit.
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From: Norte America
MBUSA
No dealer will just flash your ECU on basic service unless you are throwing codes and have major malfunctions. And dealer reflashes are done via Germany server, which takes time and effort, neither of which they will waste on your car. Flash away, the only way they will find out is if they open up the ECU and see that it's been opened or you bring it in for a malfunction and they start looking for reasons to deny...
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2012 C63 coupe
Again it's up to them to provide proof that the changes made to the ECU is directly responsible for the component failure. The investigation for that proof is most likely more expensive than honoring the warranty unless it's something very obvious.
Google "FTC Magnuson-Moss Warranty Act" for more info.
Google "FTC Magnuson-Moss Warranty Act" for more info.
