Not sure if this should be in the tuning section or not, but I have searched here and HP tuners and posted on HP tuners with no luck yet, so thought I would try here for some help as well. I have a 05 and have been using HP tuners to tune it for almost a year with no problems. I was adjusting my speedo settings yesterday and then going for a test drive to check it. I got about a mile from my house and of course I left my phone at home, and I stopped to readjust and in the middle of the write my check engine light started flashing really fast and the write failed. I tried to write again and it says unable to connect to ecm, check cables and key to be in the run position. I walked the mile back and got my old truck and towed it back to the house.I have tried removing radio fuses, disconnecting the battery, etc... no luck still the check engine light flash's really fast and the the truck will not start. This is the first time I have had any problems with using HP Tuners.
Thanks in advance,
Bill

i had this happen to me, but pulling the negative battery cable for a while , then it would let me flash the computer and all was good.

As suggested try pulling the neg battery for a few minutes & then flash with the file that failed previously.

Had it disconnected for about 18hrs. Still no good, when you turn the key on, the check engine light still flash's really fast and it will not crank.
Thanks