Originally Posted by
Shrek
The E67 ECM is capable of both CanBus and Serial Data communications - so that is not an issue with your specific conversion project.
The tune you posted indicates the following:
The E67 ECM is programmed with a 2009 operating system - from an LH8 5.3L Colorado.
The T42 TCM is programmed with a 2006 operating system - from an LS2 6.0L TBSS - which was original paired with an E40 ECM.
You have an operating system mismatch - which is why the ECM and TCM will not communicate - hence the U0101 DTC.