OS compatibility 6l80e limp mode

I got an engine and transmition from a 2014 Yukon Denali wreck with 62,000 miles in them to swap in my firebird. Removed VVT, DOD and installed a ls3 crate engine intake/throttle body and injectors. Had a friend of a friend modify my harness and remove vats and never could get it to fire, and HPtuners stopped connecting(think the harness fried the ecm). So got a new harness from Bpautomotive and a new ecm from ebay from a 2009 Corvette and bought HPtuners to try and do everything myself. :doh:

Now it runs and drives but it doesn't shift. Driving it down the road the scanner shows it shifts through the gears but it doesn't.:banghead:

I'm thinking the OS for the ECM and TCM aren't compatible. Can I install a 2009 corvette OS into the 2014 6l80 TCM or am i missing something else.
E38 OS is 12628990 and T43 OS is 24265260

Also getting P0700 and U0100 DTC's

Tried searching the forums but could find a definitive answer and don't want to brick anything. Need help!!!!!!

Thank You.

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The P0700 and U0100 DTCs mean that the ECM and TCM do not communicate properly. This happens with a mismatch of parts or operating systems.

You cannot flash a 2014 T43 TCM with a 2009 calibration - without destroying the TCM.

Thanks for the confirmation. Jon

So now I'm thinking I'll get another ecm(Serv.#12633238) that's a direct replacement to the one that got fried, but was wondering if I would have any problems with the throttle body or anything else? The guy I bought the corvette ecm(Ser.#12625455) from made it sound like it mattered.

thanks again for the help:worship:

Using a Corvette based E38 means also using a Corvette throttle body (like the LS3 that you have) and a Corvette APP (accelerator pedal).

Using a Truck based E38 means also using a Truck throttle body (which hopefully you still have) and a Truck APP.

Depending on which route you go, two of the wires in the APP connector may need to be transposed.

Unfortunately I sold the truck intake and throttle body. So with the cost of a new throttle body, APP, ECM, and credits to tune I could almost get a corvette TCM and install that in the transmition. Would that work or am I just pissing in the wind?

Rule #1 of any LS conversion - never sell off your "spare" parts until you are 100% finished.

The T43 TCM is bolted to the valve body, inside the transmission. You would need to obtain a 2009 model year T43 TCM - to then program it with a 2009 Corvette 6L80 calibration.

A new or reconditioned TCM will often be blank - which means you would need access to GM programming tools for the initial programming. These TCMs are not inexpensive - generally between $500 and $750.

I've been learning a lot with this swap. Unfortunately it's cause I keep making stupid mistakes like this.

Guess I'll get another ecm and hopefully one of my buddies has a truck throttle body that I can get cheap.

Thanks for all the help and advice Jon.