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[uhtrinity]

So, on the sense resistors, my take is they are strictly there so the BCM can get "two subpack" averages. This would allow it to sense if the pack is out of balance voltage wise or to pick up shorted cells. The math shows that each resistor would have to dissipate about 1/4 watt or more @ 40 mA or higher. The voltage sense wires are also a very small gauge, I would think if they were meant to handle any balancing charging they would be a higher gauge. The 180 ohm resistors seem like they are there for current limiting purposes only, in this case 40mA - 50mA per subpack pair which would be 360 ohms.

When I build my real time voltage load display I'm thinking of using a multi meg ohm voltage divider to route battery pack values to the front of the car. Every 14.4 volt (18 volt peak) subpack pair will produce a voltage value to the front of about 1/2 (7.2 volts / 9 volts peak). I will be tapping off of the C connector on both packs using the same values the BCM sees. The other option I have considered is using optoisolators, though they cost more. I'm planning on 10 gauges per battery pack for a total of 20. It should look pretty and give me the real time balance monitoring I need