2012 lml os 12644096?

Hi Guys,

I tried to tune my second LML last night and ran into nothing but issues with the truck. It had H&S on it previously and when I ran the VIN through TIS it said the OS should have been 12649244. I could not find this OS in any of the file repositories so I tried to flash in the 12649244OS and the truck would not run right. Has anyone had any experiance with this? Does H&S change the OS on the truck? I did a 2014 a few days before and everything lined up and worked perfectly. But for whatever reason this truck did not like the 12649244. I ended up just flashing a stock 12649244 into the truck and then reinstalled the H&S and he was on his way.

Could there be some sort of issue with H&S trucks something like the dodge setup? Does the H&S possibly flash other controllers on top of just the ECM?


Thanks

Mitch

I would call H&S and ask what the procedure is when returning to stock.

I am sure they can explain how it works, but since no READ of the ecm is available they may only provide a single tune/OS for all 2011-2014 trucks regardless of the OS that came from the factory.

Good Luck

I shall do that. Normally something like that shouldn't be an issue but I full flashed back in the GM OS and the truck started throwing codes and having a hay day. It almost seems like H&S has updated some controllers behind the scenes so to speak and when you flash it back to stock with EFILive your only getting the one module (Similar to the whole dodge mess).

Can anyone confirm that 12644096 is a GM OS? Has anyone flashed a truck after it has had H&S in it?

Thanks for your help.

I just spoke with H&S.

They said that they are using one OS per year of truck, which I would assume for the 2012s is 4096. However in the TIS listing there is no mention of a 4096 anywhere and I cannot find one online to check. I quizzed him a bit and like GMC-2002-Dmax said they just have a default OS for each year and the truck is just flashed with a stock version of that OS. He also said that H&S does not touch any other modules but the ECM at this time.

I would have liked to get my hands on this 4096 just to try it with EFI Live and see how it went, but I dont think its one of the ones provided to us.

That OS is a very early 2011 OS and is not available anymore from TIS, if it were I could obtain a copy but if you flash the correct OS/YEAR it should be happy even stock/non deleted should still be fine as all you are doing is programming a stock OS back in, it must be a FULL FLASH to work correctly to change the OS/Segments.

Deleted is a different story altogether as there is nothing you can do with EFI-LIVE to delete the LML's.

Tony

Tony, that all makes sense. I find it weird that in the TIS setup there is no mention of that 4096OS which is why I thought maybe it was a custom sort of OS. I did full flash in both a 2012 and a 2014 OS, but its starting to look like my problems were elsewhere in the tune. I appreciate the help.

Thanks

Mitch

It shows up if you punch a early 2011 VIN# into TIS

The 4096 is the BOOT not the OS

Awesome Tony, Good to know.

Thanks a bunch