Interesting, I had my LLT bms plugged into my battery for like 6 months and didnt see noticeable drain. Could it be because of the variants of Bluetooth modules that ship with them?
Just gonna link this thread whenever people ask why I don’t use smart BMS in my production builds
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It’s not about smart BMS bad, it’s about CHEAP smart BMS bad.
Ennoid doesn’t seem to have those problems…
Voltage sense to turn it on only when your board is on or when a charger is present - so genius nobody else can do it? 
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ennoid does not have bluetooth module tho which seems to be the main problematic part
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Exactly, that’s why it doesn’t drain your pack.
It uses the bluetooth you already have on your VESC and interfaces with an app you already have on your phone.
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did you end up disconnecting bluetooth? to see if the drain is the same?
I finally saw it…
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It stopped draining while I was at work, no apparent reason
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The reason probably being the bms wasn’t connecting to your phone while you’re not there.
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Ya know I think you might be onto something there 
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If I were a little electronics ninja. I’d make an adapter for the LLT smartBMS serial interfaces that then pretended to be a CAN bus BMS that vesc suppported. (assuming vesc supports some BMS over canbus enoid? vesc bms? ).
Actually maybe i’d just use one of those other BMS or build one that worked as such.
point being vesc BLE ought to let you inspect a BMS over CAN.
Use the 5V pin from the ESC so it’s only on when the ESC is powered on?
The LLT I have has an internal BLE. Hopefully someone could figure what we can do to stop drain. I am also a victim on the drain but in a different LTT with external BLE on a brand new pack I build & left alone for months 
I’d guess that if the ble unit is constantly communicating with the phone it’ll drain faster, use more power?
Be aware that not only the xiaoxiang app keeps the bluetooth connection alive.
If you pair it with your metr module, the metr app keeps the connection open even if the metr module itself is turned off. I suspect that in the background is connection actually goes like this LLT => PHONE and not like this LLT => METR => PHONE, at least after the pairing is done.
Would be nice to terminate the LLT bt connection if the metr module turns off. I will ask in the metr thread if its possible to implement such feature.
On a different note
Do you guys think LLT/JBD would listen if we (I) would approach them with request to make it possible to switch off internal bluetooth modules with desoldering a solderable jumper?
I am thinkin something like this:
Note that those smd components are 0402 sized so this jumper pad is relativelly small and it wouldnt add anything to the BOM cost.
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not everyone wants to open up their board, dig inside their battery pack and do solder work on the bms once the board is out of storage
i rather just plug in the board for 5mins to juice up each month, than to desolder / solder anything on the bms
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Yeah it’s such a non-issue for me that I’m surprised anyone is talking about it
well you are in luck because with the proposed change all things would go the very same way then before 
I am playing with a microcontroller and trying to communicate through the UART port so the baked in bluetooth module would be just something that has the potential to drain my battery. The point would be to not change the behaviour that works very well for almost eveyone else and still have the option to customize it.
I have both the old and new versions in various boards, I haven’t seen any drain from either type.
I always set the BT to turn off after 30secs and the any balancing down to 4000mah at worst then it stops.
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