Not sure where to begin with this as I have already figured out what is bricking these batteries, but not as much as to unbrick them. TTI has changed the game on the 40V batteries as you can no longer open them and jump the two pins GND and RST after you have performed your repairs. The new generation of batteries deems themselves permanently faulted by using a host control (NXP-LPC824J) to keep triggering the device_XREADY bit on the actual BMS (Texas Instruments-BQ76930). This scenario is what people are encountering when they "go to use it for the first time this spring and, come to find out my battery is wasted". Once the battery triggers PF state the system will slowly drain the pack over a pair of 750 Ohm resistors until all cells reach zero. The problem at hand is that TTI had enabled CRP on the 824J disabling SWD connectivity. I was able to get into an 824J on a 6AH that failed and pulled pack to 0v, but only after erasing it. This is what tells me CRP is enabled, I have quite a few "failed" packs at my disposal being a 6, 7.5 and a 12 AH. I have been able to preserve the cells by desoldering the 750 Ohm resistors, the 12 is strange in the way it failed as it has not enabled the resistors to pull it down to 0v. I hate when manufacturers pull this kind of thing because these batteries are not even 2 years old and have a lot of life left and just end up in landfills. If anyone has ever gotten them to work again after entering failure state, or knows how to get around CRP please jump on the train and get the word out, this is a huge fist to the face for those who like to fix over replacing.
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