On a 2012 Sierra

Does the ECM record events from a tune where a tech 2 could tell?
Could I put stock file back and not get caught?

Thanks

 

Yes, there is no memory. Go back to stock then take it in for warranty work.

I had my transmission fail a few month ago and they found the aftermarket calibrations in the computer and still did the warranty work.

 

it all depends on the service manager..
some dont care, some are strict.

 

Do a search on this forum - there have been some robust debates over that issue and some very good information shared. They don't all agree on some of the fine points, so you'll want to read what everybody has said and make up your own mind. Interesting stuff ....

 

I had a warranty issue with my 2010 last year and did alot of research into this subject
including checking the calibration codes in my truck with a tech2.
I can tell you for sure that if the tune is returned to stock after a tune, the correct calibration codes appear on the tech2 screen. This is all they are likely to check.

What I don't know 100% for sure is if there is another way the dealer may find changes if he really, really had a reason to dig deep. Probably not, but no quarantee from me.
Also, I am not sure if this applies to 2012 model year, but it should.

The pcm's in the newer Camaro's, Vettes and I beleive, newer Duramax do record calibration changes.

If the 2012 is the same as a 2010, you should be ok.

 

Duramax ECMs 07 and newer record the last 10 checksum values flashed, but I was told that gas engine ECMs do not currently record this data. I'm not sure if this changed for 2012+ though, since my research was based on 2011.

 

they do record the last 10 or so cal's. it does show up on the tech 2 screen. gm wants a screen shot if they call for it. regardless if you put the stock tune back in it.

 

Area47: where is the flash history visible on a Tech 2? Have you seen it? We have had guys (Allgonoshow being one) go over their reset tune with a Tech 2 with no ability to view past flashes; if you know something we don't about the Tech 2, feel free to share. According to GM's service bulletins, only late-model Duramax and Global A ECMs record flash history.

 

Are you sure? When did they start this for gas engines?

I heard the ECM is capable, but check sums aren't recorded except for latest flash.

I know on diesels it records last 10 check sum values.

...

 

yes, the global a vehicles... new camaros, duramax use GDS. reflashes can be detected.

tech 2, as far as i know our trucks up to and including 2012 can be flashed back to stock without detection. someone correct me if i'm wrong here..

bulletin from camaro5.com:

"#09-06-04-026B: Identifying Non-GM (Aftermarket) Engine and Transmission Calibrations for V8 Gas Engines Using Tech 2 or Global Diagnostic System (GDS) - (Apr 7, 2010)

Subject: Identifying Non-GM (Aftermarket) Engine and Transmission Calibrations for V8 Gas Engines Using Tech 2® or Global Diagnostic System (GDS)


Retrieving Calibrations From a Global A Vehicle

This information applies to the 2010 Camaro and is typical of the procedure that will be used on Global A vehicles.

1. Turn OFF the ignition.
2. Connect the MDI to the Data Link Connector (DLC) of the vehicle.

Note: Use the USB port to make the following MDI connection:
3. Connect the MDI to a PC or laptop that has been downloaded with the GDS application from TIS2WEB.

Note: At least one Diagnostic Package must be installed on the PC to perform diagnostics.
4. If GDS was just installed, select: Add New Diagnostic Package and then select: a Diagnostic Package to download. Click: On the GDS icon on the PC.
5. The Login Page will appear.
6. Select: A User.
7. The ID Screen will appear.
8. Select: The serial number of the MDI being used.
9. Select: Connect.
10. Verify that the system status is ready by observing for a flashing PC light icon on the MDI.
11. Select: Make, Model and Model Year, in order to build the vehicle.
12. Click: Upload VIN, to allow the VIN to be reported to the PC.
13. At: The Verification step, turn ON the ignition, with the engine OFF.
14. Select: Next Action.
15. The Home Page will appear.
16. Select: Next.
17. The Diagnostic Screen will appear.

Note: Due to vehicle build, software and RPO variations, GDS may ask for additional information in Step 18.
18. Select: Engine ID, if prompted.
19. Select: Module Diagnostics.
20. Select: ECM.
21. Select: ID Information.
22. The Diagnostics page will appear.

Note: GDS is capable of displaying up to 10 Calibration History events.
23. Select: Calibration History from the drop down menu in order to display the following items on the screen:
• Calibration History Buffer
• Number of Calibration History Events Stored
• Calibration Part Number History
• Calibration Verification Number History
24. Select: Screenshot.
25. Name and save the file in an appropriate folder.
26. Select : Print, and retain a copy of the screenshot with the repair order.
27. E-mail a copy of the screenshot to xxxxxx@gm.com. In the subject line of the e-mail include the phrase "V8 Cal" as well as the complete VIN and Dealer BAC. In the body of the e-mail, include the VIN, mileage, R.O. number and BAC. Include a brief description of the customer concern and cause of the concern.

Note: The dealer will receive an e-mail reply after the calibrations have been validated. The e-mail reply will advise the dealer if the calibrations are OEM.
28. Allow two hours for the PQC to verify the calibrations and set up the case details.
⇒ If the PQC determines that the calibrations ARE aftermarket calibrations, DO NOT contact GM Technical Assistance to discuss warranty concerns on the aftermarket calibrations. ALL questions and concerns about warranty should be directed to the dealers Fixed Operations Manager (FOM), (Warranty Manager (WM) in Canada).
29. You may call the PQC two hours after submitting the e-mail for authorization to replace the assembly. This will provide them time to receive, review and set up a case on the request. Please be prepared to provide all the usual documentation that is normally required when requesting an assembly authorization from the PQC.

Warranty Information
• The Dealership Service Management must be involved in any situation that would justify the use of labor operation Z1111.
• Notify the Fixed Operations Manager (FOM) (Warranty Manager (WM) in Canada) of the situation.
• All claims will have to be routed to the FOM (WM in Canada) for approval.
• Please refer to Corporate Bulletin Number 09-00-89-016, Labor Operation Z1111 - Suspected Tampering or Vehicle Modifications for important information."