62kwh BMS Pinout Help

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New member
Dec 27, 2023
Hey everyone, I’m in the process of converting my BMW E30 to electric using a 62kwh 2019 Leaf Pack. I’m currently splicing all of the BMS wiring to fit the longer distances they need to travel. To assist me in doing this, I am using a 2016 wiring diagram as pictured below, which gives me most of the information I need. Nissan does not like to change things, the BMS is the same as in the other packs (black and grey connectors). I have come across a terminal which I can‘t seem to identify using the diagram. The terminal is pictured below, I have traced it to pin 89 on connector LB15. This is the only terminal like this in the pack, so if anyone knows or can determine its purpose I would be very grateful.

Should I connect it to any positive terminal on the pack like it’s connected, or does it have to be connected at a specific point in the pack?
Should I bother connecting it?


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It looks to me that it might be important to connect it to that exact spot. It might even be measuring voltage drop across a busbar, although that seems unlikely. Is that spot not convenient?
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It's not that it's inconvenient, it's a pretty easy thing to add. I just wanted to know what the purpose of the terminal was so I could make sure the BMS has the right info. Thanks.
According to your diagram it's connected to the + terminal of cell 49 via the bus bar, while 110 connects to the - terminal of cell 49.

I would guess it's needed to monitor cell 49, so would assume it's pretty essential.