Mercedes Dealership Warranty Issue
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c63
Mercedes Dealership Warranty Issue
I heard that MB dealers cant tell if you tuned your ECU unless they flash the car themselves? Does anyone know the details on this topic. I really want to do this but im scared to loose the warranty on the car.
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From: Palos Verdes
'09 C63
Ok instead of asking you to search on this one....
If you get your ECU modded they shouldn't be able to void your warranty just tell them to reflash it to factory setting that's it.
If you get your ECU modded they shouldn't be able to void your warranty just tell them to reflash it to factory setting that's it.
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From: Clifton, NJ
96 and 08 911 turbos
How dumb do you think MB is?
If you go in there with a broken pcv hose, then sure, they probably wont' take the time to check.
A fried tranny or major engine problem, and you better believe they'll go through the software.
If you go in there with a broken pcv hose, then sure, they probably wont' take the time to check.
A fried tranny or major engine problem, and you better believe they'll go through the software.
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c63
I was told from a freind of mine that works in a Bmw delership, that when the cAr comes in for service. They scan the whole car and if an ecu was tuned they detect it, but they don't tell the owner of the vehicle anything, untill somthing goes wrong, then they void the warranty. He said that their stressing this more nowadays because the economy and all.
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I was told from a freind of mine that works in a Bmw delership, that when the cAr comes in for service. They scan the whole car and if an ecu was tuned they detect it, but they don't tell the owner of the vehicle anything, untill somthing goes wrong, then they void the warranty. He said that their stressing this more nowadays because the economy and all.
Most of the guys who do the K1 flashes send A LOT of their customers to tune friendly dealers making those dealerships a lot of money. They would be stupid to start punishing those people.
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I know this is an old debated topic, but this is what was verbatim from dealers in Atl:
RBM North/South: They don't like to deal with modded cars due to issues that can arise from tunes. So, if you have a problem, and they find it was tuned, warranty does not cover.
Buckhead Mercedes: Warranty is in effect if they installed the Kleeman or Renntech package themselves.
Atlanta Classic: Mod friendly, Kleeman and Renntech.
Mercedes South: Ownership has changed, so I am not sure of current status on dealing with tuned cars. Previously, that dealer got on my damn nerves, and apparently a lot of other owners. They lost a lot of business to RBM, guess that's why they are under new ownership now.
It varies so much these days with dealers.
RBM North/South: They don't like to deal with modded cars due to issues that can arise from tunes. So, if you have a problem, and they find it was tuned, warranty does not cover.
Buckhead Mercedes: Warranty is in effect if they installed the Kleeman or Renntech package themselves.
Atlanta Classic: Mod friendly, Kleeman and Renntech.
Mercedes South: Ownership has changed, so I am not sure of current status on dealing with tuned cars. Previously, that dealer got on my damn nerves, and apparently a lot of other owners. They lost a lot of business to RBM, guess that's why they are under new ownership now.
It varies so much these days with dealers.
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12C P85DL
This is a topic near and dear to my heart so here is my two cents worth-
There is a function call that can be issued to the ECU that requests a Software Verification Number from the ECU. This number is a glorified checksum. If you change one bit of the code in the ECU, the SVN will change. Tuning is changing bits, so yes, someone can tell if you have a moded ECU by doing nothing more than connecting to the OBDii port.
I believe the SVN process is mandated by the EPA so that one day emissions stations can plug into your car, do an SVN then compare the number against a data base provided by the manufacturer to see if the software has been changed. Each software release has its own SVN and there is a database for these things.
The EPA is also very insistent that Tuners do not muck with the SVN process to provide the correct answer even if the software is modified. That is a huge no no.
I believe the only solution to this issue is to provide the owner with the capability to choose between stock and modified software. The owner can then make the decision as to when they use the modified software and when stock is appropriate.
Returning a car to the dealer for service would seem an appropriate time to have stock software. If the Tune is not EPA certified, then leaving the track would seem to be an appropriate time to install stock software.
This capability exists. I have asked for and gotten permission from the forum admins to do a technical article on the subject. With luck, I’ll get it done and try to shed some more light on the technical issues involved.
I know this is going to draw fire but I am also a fan of customers being in a position to choose between two different tuned files at will. One example would be a high octane file for drag strip runs and a normal tuned file for track days. The other might be a customer that wants to compare Tuner XYZ's tune with Tuner YZX. Again, just my two cents worth....
There is a function call that can be issued to the ECU that requests a Software Verification Number from the ECU. This number is a glorified checksum. If you change one bit of the code in the ECU, the SVN will change. Tuning is changing bits, so yes, someone can tell if you have a moded ECU by doing nothing more than connecting to the OBDii port.
I believe the SVN process is mandated by the EPA so that one day emissions stations can plug into your car, do an SVN then compare the number against a data base provided by the manufacturer to see if the software has been changed. Each software release has its own SVN and there is a database for these things.
The EPA is also very insistent that Tuners do not muck with the SVN process to provide the correct answer even if the software is modified. That is a huge no no.
I believe the only solution to this issue is to provide the owner with the capability to choose between stock and modified software. The owner can then make the decision as to when they use the modified software and when stock is appropriate.
Returning a car to the dealer for service would seem an appropriate time to have stock software. If the Tune is not EPA certified, then leaving the track would seem to be an appropriate time to install stock software.
This capability exists. I have asked for and gotten permission from the forum admins to do a technical article on the subject. With luck, I’ll get it done and try to shed some more light on the technical issues involved.
I know this is going to draw fire but I am also a fan of customers being in a position to choose between two different tuned files at will. One example would be a high octane file for drag strip runs and a normal tuned file for track days. The other might be a customer that wants to compare Tuner XYZ's tune with Tuner YZX. Again, just my two cents worth....
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E63 P30, CL500 Sport
The shop foreman at a Mercedes dealership told me that the dealer can indeed tell if one has a modified ECU. Technically they are allowed to void the warranty of the modified (or aftermarket) part and all other parts that can fail due to the modified or aftermarket part. However, as others have already mentioned, there very few mod-friendly dealerships who will work with the customer.
Last edited by MB_Forever; Sep 3, 2009 at 06:32 PM.
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This person must not be familiar with MB's theft relevant parts process. As mod friendly as I am I would not sell a customer an ECU. ECUs are the same as EIS/KEYS we do not sell them over the counter the car needs to be in service with an issue with the vehicle's ECU to order the part. He could lose his job if they get audited which they do periodically for these types of sales. If you do plan to go this route I suggest purchasing the ECU prior to modding the vehicle.
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From: Long Island, NY
SL63
Why not just install a Renntech R.A.T. and pop it in and out as needed ?
http://www.renntechmercedes.com/
http://www.youtube.com/watch?v=1zsL3EJzutw
http://www.renntechmercedes.com/
http://www.youtube.com/watch?v=1zsL3EJzutw
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From: Orange County, CA
GMC - Miata - Trek - P-Car
This person must not be familiar with MB's theft relevant parts process. As mod friendly as I am I would not sell a customer an ECU. ECUs are the same as EIS/KEYS we do not sell them over the counter the car needs to be in service with an issue with the vehicle's ECU to order the part. He could lose his job if they get audited which they do periodically for these types of sales. If you do plan to go this route I suggest purchasing the ECU prior to modding the vehicle.
MBUSA has several protocols to be followed when their dealers furnish theft-relevant parts.
TRP documentation…
http://www.startekinfo.com/StarTek/o...tedDocId=10447
http://www.startekinfo.com/StarTek/o...tedDocId=10448
http://www.startekinfo.com/StarTek/o...tedDocId=10446
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12C P85DL
