lb7 ecm flash trouble

03 lb7...downloaded ecm cal has out of range c0301. got ecm tuned as needed with dsp5 os but it will not flash. It cannot erase ecm flash memory(reason:negative response $31). does this even when trying to flash stock file in. ive never had this issue before and don't want to go to far and brick the ecm. any help is much appreciated.

yes I do have most recent updates and have pulled fuses for different acc. will not even read ecm in high speed so its not being tried flashing either. truck starts and runs

I often have problems with the lb7. I find that if the truck has an aftermarket radio I just pull it out and disconnect the harness and that always works for me. If it has a remote start or alarm they need to have their fuses pulled out as well. Aftermarket electronics has gave me a lot of problems with the lb7 and lly so first thing I do when I tune one is remove them all.

Good advice, that is what we say too and 90% of the time it solves the problem.