I was wondering if the dealer could detect if I have flashed the ECU but flashed it back to stock before I go in for a service or somthing?

D3 says Toyota hasn’t started doing that yet

 

Highly unlikely unless you have a CEL or they rev your car to 7200. Get all my service done at the dealer and no issues.

 

I agree on this or not unless the service that is being done is ECU related (like CEL). Worst would just be the dealer flashing your ECU to stock without even telling you.

My first experience on my IS with the dealer was awesome - went there for a tranny leak and the GPS recall. They ended up fixing my request + replacing my passenger engine mount, which I didn't reported (and didn't even know). The only comment I heard was - lexus tech noticed a vibration in the cabin (due to my after market exhaust - PPE headers + Ark Grip). I'm sure they all knew the ECU has to be tuned to prevent CEL errors from PPE headers.

I even got a compliment when I picked up my car (kindda little embarrassing coz my car was the only loud car in the service center). It really felt like a bastard child returning home .

Correct me if I'm wrong, but I think the rev to 7200 only unlocks in a 3rd and 4th gear with a combination settings (manual+ sport/sport+ + vsc off) so they will have to drive the car to see it.

 

IS 200t and ISF both tuned, neither detected.

 

Since mine isn't tuned yet but I plan on doing so, I just asked the mechanic at the Lexus dealer if the car would tattle one me. He told me they would not see a tune and they would have to look for it in order to see that it's tuned (throttle maps and timing curves and such).

 

I did not design or programmed a lexus ECU, but I do work as a software engineer. If I were to implement re-flashing, I would add the means of detecting what version of the software is installed on the ecu, including some form of a hash. Any change to the program(one symbol change would be enough to be detectable) would cause the the entire hash value to change, thus indicating that it was tempered with. I am fairly sure they can detect it. But being as lazy as they are, dealer technicians might not be that bothered to check it in reality, unless they absolutely have to.

 

At this time Toyota has no means to detect ECU tunes. Maybe in the future they may develop that ability within the Techstream software, but right now it doesn't have that feature.
Considering the focus of which Toyota builds vehicles, the vast majority not being performance orientated, ECU flashes is probably not a item that's even on their radar, or so far down the list of things to address, that it's probably never going to happen.
Looking at the entire Toyota lineup, I could see someone tuning an FRS (or whatever it's called now) and the new Supra. All those other cars that you would have tuned: any Supra, MR2, Celica GTS Turbo AWD, Celica GTS/Matrix XRS, etc. are all long out of warranty.
Flipping over to the Lexus side, looking at vehicles within warranty, thing that may get tunes are: IS (duh!), GS/F/RC/F, LC, LFA. Looking at that list, except the IS the remainder are not high number selling vehicles...so once again, do you pour effort into flash detection software.

If you look at Audi and Subaru (mainly WRX/STI), right away they are looking for ECU flashes, but they also don't build vehicles with the same focus as Toyota...and the WRX/STI have significant numbers on the road.

 

Im not a Toyota tech or software engineer but there is absolutely no way they can’t detect a tune...IMO.
They might not look for it for exhaust, or suspension, or brake work etc but I’m sure if someone blew their engine or tranny or major component and they suspected abuse/mods they would absolutely be able to see if the ECU was modified. They probably don’t look often, but I’d bet anything they have the capability to check if the ecu has been flashed.

Hopefully someone who knows 100% can chime in but I just don’t see how it’s possible that Lexus can’t see if you’ve modified your ecu.

 

you might be right. But it also could be that techstream simply does not pull that from the ecu memory. The moment Toyota realizes that a significant chunk of money goes toward covering tuned up blown engines, they will either modify how they store / reflash the ecus or will simply start pulling data from the existing ecus, stored as some obscure hex/binary data counter/string no one thought as useful (other than toyota eng team members).

you would be surprized how much additional data engineers sometimes could use/store in addition to that which you can see and have access to. Black box crash recording comes to mind. I dont know if techstream hardware can look into that data, but Toyota def can and does tell you that in the manual.

 

I guess we have to first land on what we mean by "detect".
For Audi, as per my buddy that works there as a tech, once they plug in there diagnostic computer, it automatically scans the ECU software looking for a tune, and once confirmed sends the data directly to Germany to flag that VIN...he, as the tech, doesn't need to do anything.
For Subaru, as per my buddy that used to work there, basically it's the same scenario, but the info goes directly to Subaru Canada...would be kinda weird sending it to Germany lol
For Toyota/Lexus, the Techstream software doesn't send anything anywhere...not to Japan, not to Toyota Canada...and it doesn't scan for tunes, cause it doesn't have that capability.
If someone blew their motor or tranny, might they think a tune was the cause? Maybe, depending on the vehicle. If a Highlander blew a motor, guaranteed no one cares...just put a long block in it and out the door it goes. Toyota will recall the engine to determine what the mechanical failure was...if it's a one off or first time that it has happened.
If someone blew a motor in a new Supra, I'm sure someone is going to care. At the dealer level could they detect a tune? No. Could Toyota Canada recall the ECU to head office for further checking, or even send it out to a third party to verify it is has been tampered with...absolutely. If they are footing the warranty bill they can do whatever they want.

If the vehicle is operating normally when brought for regular service, there is no reason to connect the Techstream to the vehicle...hence right there no one is checking for anything.
If the vehicle suffered some catastrophic failure and was towed to the dealer, for sure the first thing they will do is look for codes in the system that might explain the failure.
Attached to those codes is Freeze Frame data...basically a recording of the fault...just prior to it happening, when it happened, and shortly after.
That Freeze Frame Data will capture all the operating parameters of the engine and transmission at the time of the failure...now, could someone looking at that determine that the engine rev'ed to 7500RPM...sure, and they might even realize that the car isn't supposed to rev past 7200RPM. This will likely raise a flag...but to outright say that the car has a tune...it's just not possible.
Techstream isn't tuning software...so it can't see fuel and ignition maps...you can see injector volume and ignition timing as it's occurring, among the hundreds of other data fields, but unless someone is well versed in what they are looking for, and when a parameter is out of spec., no one is going to know.

Techstream identifies the engine and tranny software via a Calibration ID number for each. Unless someone changes that ID number, it will all look the same on the Techstream, tuned or not.
I think the question should be posed to the tuners, are they changing that ID number...my personal opinion is no.
Also at the dealer level there is not a list of ID numbers that they can compare to and see if the car has the correct ID numbers or not...at head office they can certainly confirm that...whether they have the data or it has to be retrieved from Japan.

Believe it or not...but it is what it is.
If someone else who knows 110% for sure...feel free to chime in and agree with me (lol!)

 

That is some nuclear option right there, lol. Someone at Audi def got fed up with tuning ruining their business model, lol.

 

7200 Rev limiter is available at anytime. 1st, 6th, N, P, etc. All they have to do is bury the needle and they will be able to tell

 

I dont think Lexus or Toyota has reached that level of advancement yet where they have ECU black box with data logs etc......Lexus can't even get a forced induction performance car out the door

 

well, that is how they were able to prove that they were not responsible for some very famous “unintended acceleration” cases. They log the data in a continuous loop before the “impact” event. The data includes vehicle speed, brake and throttle positions, engine rpm, and other pertinent data points. That data is only accessible by toyota, and the data is persistent if the power goes out. Toyota dont have to be “that advanced” to do that. All the data points are there already, they just have to collect them and store them in some persistent memory, which they evidently do.

 

All that is true about the “unintended acceleration” cases except for one thing...all that data you speak of is in the Airbag ECU, not the engine ECM. The ECM does not record crash data, only the Airbag ECU.
Should a DTC have been set due to a fault, then the engine ECM could record data...and if that DTC was set as part of an accident, then the DTC may contain Freeze Frame Data...but it's not guarantee every time a DTC is set that there is Freeze Frame Data.
All the data that Toyota pulled from the vehicles was actually pulled from the Airbag ECU, after it is removed from the vehicle and connected to specialized equipment.