@Cougar281 Can one still load a fresh bin into these newer 87A TCM's using older ofline GM tools? Or does it require an unlocking using online TIS account? Guessing HPT tool is how everyone is currently doing it.
While I have raw A bin, along with everything required to make that thing say uncle however ya wish, currently no matching hardware on hand to test against my MDI. After reading some FB posts, seems ATS customers are seeing some com issues. As much as I plan to make this deal plug-N-play, I'll happily write out or modify the parts the TCM pissy about in a custom bin, if that make the whole deal go smoother. Then we can work the bugs out in beta testing.
Besides just sending basic CANbus packets with stuff like RPM, torque values, and throttle position, GM also includes 1bit Validity Status related to these messages. So while the TCM looks for a torque value under ID 0x123 byte 2, it also looks at say bit 7 for a 1/0 to tell it that Torque # is valid or not. Which luckily they use 1 for valid, and 0 for invalid.. IE, no bit or byte present = data invalid..
Knowing where these switches are in the OE bin, one could make it ALWAYS accept the values received, rather than questioning every packet. Or even ignore data we don' want it to use. Basically write it out like a DTC, including the triggers for Limp Home..
