LLY fail to write

[American-Thunder]

Hi All,

I have a 2005 LLY that I recently did head gaskets and while I had it apart I decided to put a larger turbo on it along with a larger intake so I wanted to make some updates to the tune since I had an MPVI3 I had purchased for an LS project I am working on. I downloaded the stock tune file no problem, and made several revisions which successfully were written but on or about the 5th revision I got the message that it had failed. I tried it again using the write entire option and it fails attempting to unlock the bootloader. I tried it fast and slow same result. Sometimes it gets to 100% and fails to verify if I am just writing the calibration. I have the radio/amp/info fuses removed and the batteries on a charger. I believe the problem is the VIN is gone. I now have a no crank situation where it doesn't even attempt to turn the motor over. In a last ditch effort to see what the problem my be I pulled out my scan tool and it won't even read the vin which is what makes me think that is the issue. After reading here and a few other places a bit I attempted to write the VIN information which also failed.

At this point I am lost. Not my first time tuning a vehicle but then again I've never had it fail. Did I brick this thing or is there anything I can try to bring it back to life?

Thanks in advance!

[American-Thunder]

In case anyone is ever searching in the future. I tried everything. Removed every fuse I could ABS, TCM, RADIO, AMP, and others. Then I remember when I flashed the first tune that my steering wheel controls stopped working. I have an aftermarket radio but I figured the radio fuse took care of that. I removed the radio and saw the pac unit still had a green light on so it was powered. I removed it from the truck and was able rewrite the entire tune to the ECU. Moral is if you have one of these disconnect it and it might help ya get flashin!

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