T87A can't read, needs update?
A friend from the local Camaro club has the same v6 as I do, but 2017 (mine is 2016). He has the same E82 that I can read with MPVI3 with no issues, but he has T87A vs T87 in my car and it fails to read and requests a GM service update. AFAIK the locked TCMs of the A series could be read, but could not be written. Did I get this wrong and it should be unreadable? I was not able to read any trans related parameters correctly with the Scanner except for the gear and shaft RPM - they were all stuck at 0 or default value. But using the Xtool GM service tool replica it sees all the modules correctly and performs clutches relearn and other service procedures.
His car had issues when he bought it - before he went to GM official service here in Ukraine and updated the TCM block he was not able to switch to Sport mode for the trans and exhaust (he has NPP). Guys at the dealership told him that the trans "was not seing the engine properly" or something like that, he doesn't remember. Could it be that his TCM is from a donor and someone messed up the original? Or maybe someone has encountered the similar issues? Please weigh in if you have any info on this
Thanks
