Opened the board. Fets on one side blown. Lovely.
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Which stormy?
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60D+
how many motor amps were you pushing, may I ask?
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- This was my lower power reliable board…
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Thats a resistor tho right?
Wonder if its only that… would be an easy fix.
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I have a donor board. I’m gonna try fixing it.
I’m thinking fets also blew bc of the motor short. Will c
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twinsies!
I have no idea what happened. I’m using radium 205s, put my board down, gave it a good throttle, shuttered and would not turn off. Only one side was rotating and so I opened it up and saw that. Ordering makerX anyways 
Similar thing here. Turned it on and it wouldn’t turn off, only one side spun
I never see anyone running a trace wire to repair this kind of thing, given the cost you would think there would be a demand
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Anyone skilled enough to do this repair well probably is already working a very lucrative job and wouldn’t do this kind of stuff for less than the cost of an ESC.
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Maybe if I get good enough at this stuff in the next year or few, I can offer it as a service
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Extremely frustrating how easy the experts make the required slight of hand look
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I wanna try fixing this. If all it needs is that lead fixed I think I can do it
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Charles! I have a question. Can’t think of anyone better suited for. Lacroix Jaws 2.0 version. After I switched out the stock belt drive for the BN M1-AT Gear Drive and replacing the stock 6389 190kv’s for 63100 190 kv’s the board would not charge. Charger showed green as if fully charged but was no charge left.
After downloading the xiaoxiangBMS app it started to charge properly again!
But now It will not charge again. The battery shows fully charged in xiao & stormcore app and shows green light on charger again but it is not fully charged.
I’m seeing:
- a MOSFET software locked alarm
and also:
- A cell over voltage protection alarm
Any ideas?
Preesh!
I answered on reddit, but I’ll copy the answer here too.
To recap: The board charges completely normally until the battery is right near full charge, then the BMS voltage readings start becoming sporadic. This is then triggering over voltage faults and shutting charging off even tho the charger is connected. That is why you see the normal balancing screenshot and then the next screenshot, in the same minute, with two cells showing massively over voltage.
Obviously that voltage jump is impossible to have actually happened, so it is clearly an issue with the BMS accurately reading the voltages of the cells.
To be frank I don’t know for sure how to fix this as I’ve never implemented a fix for it before, however I can tell you from my vast experience with this BMS that this is a Lacroix application specific problem. That leads me to the belief that the lacroix sentinel is the root of this issue as no other board has that device in it.
I know for a fact the BMS needs a strong ground to the pack negative or you will get funky readings at all voltages. I have no idea how/why the sentinel would cause this specific kind of issue, but my theory on how to fix this issues is to add a wire from the battery pack negative to the BMS directly (B-) bypassing the flow through the sentinel as it’s wired from lacroix.
Hope that helps, and if you do try and implement this please, let everyone know how it went.
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I sincerely appreciate the detailed reply. I’m hoping to find an easier fix as physically rewiring or adding wiring is rather intimidating for me as I am not the most technically experienced guy. (my first board). Are there are any other possible options?
Xiao app seems to show full charge but its really only at about 65%. If I drained more of the battery before trying to recharge would that help? Thanks!