Koowheel keeps totally stopping after using the brakes

Hi all,

I’m pretty new to building custom boards and need help. I’ve got a 3rd gen koowheel kooboard (I know, terrible board) and changed the connector on both the motherboard as the battery, because the connector kept breaking. Since I did that it worked like a charm. I wanted a second battery, but the gen 1 aren’t made anymore. So I asked the seller if the bms was the same on the second gen and he told me it was. So I changed the connector on the gen2 battery as well and connected it. It seemed to work just fine until I had to use the breaks. Every time I use the breaks the controller starts to vibrate and the wheels block until the board has stopped completely. Only then I can continue to drive it again. Until I need to use the breaks again. I checked the connectors and everything seems to be fine. I didn’t do any bms bypass. Didn’t change anything on the board and battery except from the connectors. There I literally cut at the end of the wire and replaced the connectors. I am using the original remote as well. Its still working with the gen 1 battery.

Does anyone have any idea what this could be and how to solve this?

Here some pictures:

The gen 1 battery

The gen 2 battery

The new connectors on both the battery as the motherboard

And the voltage on both the gen 1 and 2 battery’s

Thanks for your reply in advance.