So, I received a blank MM3 and got it wired in with no issues.
I communicated with ECM, got the stock file, and saw that the digital gauges worked.
I also successfully updated the firmware of the MM3 using the MM3 Agent.
Once I got the tunes, I loaded it onto the card and into the MM3.
I proceeded to program the custom tune, which started but never reached 0%.
It said low voltage, but I had a battery charger connected, so I connected a stronger battery charger and tried again.
It failed several times, and NOW whenever I press ECM on the MM3, it immediately shows an error and says, “ECM is not in Application mode!”.
Several posts indicated that I should put the MM3 in the fridge for 30 minutes, so I tried that and got the same result.
I also tried unplugging the OBD port several times for a couple of minutes, and there were no dice.
At this point, I’ve emailed MM3 and am waiting to hear back, but my truck won’t start, and I’m a little concerned.
Has this happened to anyone else?
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