Detecting a tune
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GLS450
Detecting a tune
So I had a long talk with an MB technician today. Said MB won’t detect a tune if the ECU is returned to stock AND the CVN number match the last update. He said that CVN number match is important because they change it with every software update. Those numbers go to a central database and if they don’t match the car is flagged. The implication is that if you return it to “stock” for another maintenance and use and old CVN even after they’ve done a software update it will flag. Was wondering if any has heard of this??
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2020 McLaren 720s Spider
So I had a long talk with an MB technician today. Said MB won’t detect a tune if the ECU is returned to stock AND the CVN number match the last update. He said that CVN number match is important because they change it with every software update. Those numbers go to a central database and if they don’t match the car is flagged. The implication is that if you return it to “stock” for another maintenance and use and old CVN even after they’ve done a software update it will flag. Was wondering if any has heard of this??
After its done, there may be an issue where you have to send back your ECU or HHT for updating. Again, pretty rare moment...most of us will never have a software update for the life of the vehicle.
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‘24 BMW iX M60
He's referring to the STAR system that is essentially the blueprint for the cars build. Its a master record of all of the aspects of the car. People that have changed to the latest NAV or updated to the facelift headlights will have their mods fail post updates because of this - it resets to what is supposed to be factory settings. These kind of resets, or updates are pretty rare....like count on one hand rare. For your tune, if you had an HHT and returned it to stock before your service, it should go through without an issue.
After its done, there may be an issue where you have to send back your ECU or HHT for updating. Again, pretty rare moment...most of us will never have a software update for the life of the vehicle.
After its done, there may be an issue where you have to send back your ECU or HHT for updating. Again, pretty rare moment...most of us will never have a software update for the life of the vehicle.
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2020 McLaren 720s Spider
The issue isn’t having an official firmware update from MB, but rather getting a tune to modify the ECU, reversing the tune back to OEM for maintenance purposes, and then taking the car in for routine maintenance or say something with the DCT; Suspension, etc. needs looking at. The tech hooks up the Star system to the OBD 2 and bingo, the count, (number of times software has been modified in the ECU?) is off. MB can then state the ECU has been modified and you could well have a warranty coverage right on your hands. It becomes a crapshoot.
That said, SO MUCH of this depends on your dealer and the relationship you keep with them.
Last edited by Skilly; Feb 12, 2023 at 12:37 PM.
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amg gtc
thks so the best way to avoid this is with a Racechip box then https://www.racechip.com/presse-news...-63-amg-s.html as opposed to an ECU tune
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According to the page linked below, they should have released a RaceChip unit for the GTS by now. They were working on one that plugs into the ECU connector due to the difficulty of reaching the sensors (I know it was a chore on the C63 S). I run a RaceChip on our C43 and find that it works well, offers a nice improvement while still being very driveable (street and track). If you drive conservatively, I've also recorded slightly better mileage (with the RaceChip in "full on" mode, which is where it always is, for me). While there are options that provide a greater performance boost, if you're looking for a nice, no-hassle (and removeable) boost option, in my experience RaceChip is a good choice. I also like that it retains most of the safety protections built into the ECU.
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amg gtc
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2020 McLaren 720s Spider
These downstream tunes NEVER integrate to the car like an ECU tune. They have glitches and create inconsistent behaviors with the motor like cut out/hesitation. I've used this product on a C63s and ended up ripping it out.
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AMG GTR
By far the simplest is a second ECU. Any good tuner can do that.
On the 190, the ECU is freely and conveniently accessible.
With 2 x brackets, you don't even need tools. The exchange then takes 30 seconds.
The fewer parts, the fewer things can go wrong. :-)
Best regards
Stenzel
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2020 McLaren 720s Spider
