Hey!
I have a CBXR which is exhibiting identical symptoms. Outside temperatures around 6 C or lower and the board starts throwing error 17, even though diagnostics show battery temp around 15-17 C.
I have measured the resistance of the thermistors and they seemed fine-ish (between 10.2 and 10.3 kOhm at room temperature), but I went ahead and installed a new set of thermistors anyway. I have yet to test it out as the glue is still drying.
Here they are visible after plucking them out of the pack. It was strange to find them just hanging there, without actually being attached to anything, and covered by a thin layer of tape. I've decided to glue them to the cells to get a more accurate reading.
But I am still hesitant that this will fix the issue.
Is there a known problem with the BMS where its internal resistance becomes too high with cold weather that it triggers the fault itself, even with working thermistors?
Anything else I could check?
The board is a 4209 without a chip. Battery is around 4 years old and I am a new owner. Previous owner said he has never ridden in weather colder than 15 C ambient...
Thanks for any input!