2016 Gem Factory BMS

Hey I thought I would share some info and Ask a Question, First I will start with asking a question

We have 2" 2017 Gems. car #1 Had the 4 12v Battery’s linked together for a 48v system
car #2 Had the 6 8v Battery’s linked together for a 48v system

We swapped the Battery’s from car #1 with car #2 but the Factory BMS is still showing the range and distance available from the previous battery pack EXAMPLE the car with the larger battery pack(6 8volts) is still showing the range that the previous smaller battery pack would give you, I was told that the BMS needed to be reprogrammed to show the larger pack? Is this true

Where is the Factory BMS located? Question if I was to swap out the factory controller from car #1 with car #2 would that fix the problem?

Ok here is the sharing some info, The Distance Batterys (6 8volts) sue a complety diffrent (removable battery tray, So if you have the Smaller battery pack and you decide to put the larger battery pack in you car your gonna need the New battery tray, and Vica Versa

So I have not seen a part for the BMS in any of the parts diagrams in putting my 16’ back together. To the best of my knowledge the Sevcon’s are not capable of BMS functionality, but they do have a setting for number of cells and max min voltages. That might be where the range is coming from, you can check each controller in DVT in the tree under “Battery”.

I’m quite sure bms is a discrete part. In any case it’s all part of the can control system.
I have my doubts that any of the can modules can be swapped without issues. On the other hand, try it and see.
Friends don’t let friends use lead!

As normal - David is correct it appears -
This is listed as a part - I assume BMC is Battery Management Control or something like that.

Here is the pic - Part number 4

This says un-programmed so again I am guessing that they can be programmed for Flooded/AGM/4/6
If you swap those modules, it “might” work.

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Hey Thanks for the Parts break down. I’m assuming this is what reports back to the dash display and gives you a SOC on the display, Ill see if one can be swapped for another

I think it is programmed in the main brain . Pretty sure the dealer can change it .

I have a Gem mechanic that has offered to re program both cars but that would require ME towing each car to the dealer (150 miles away) each way for him to reprogram each car. Totally not worth the hassle. I was looking for a quicker solution. Like swapping out BMC, units
I’ll take a look around and see if it’s easy to get to/swap out. It’s gotta be easyer then towing all over creation

Well I swapped BMS’s between cars. The factory BMS is not in a great place to work and it’s got a pretty large group of wires going to it as well as the plug in the middle. But swapping BMS’s between cars seemed to fix everything. Here is what the factory BMS looks like