Ducati City Pearl - BMS bms KL3688CR3 issues

[giles202]

Hello to all

A friend of mine bring me this bike to get it back on the road. After checking the battery totaly dead, I open the case and I've found the cells completely rusted.
The bike as a litle display on the hands bar showing the number of cycles and the battery capacity, allong other informations.
I've build one external battery aside to check if the problem was only the battery. I've use the original BMS inside. Everything was fine, so, I've order new cells.

After full assembled, the bike is not working. There is 3V of voltage drop between the battery and the BMS output. The BMS is build with 2 boards, with connection to 2 temperature sendors glued on the battery, ON/OFF switch, charger port, and the 2 lines for data transmission. One of the pcb's as the reference KL3688CR3. Those type of BMS, ususly called as "smart BMS" are always a probllem because then I can not find them on the market and I have to swapp To a regular BMS. The point here, is that if I do that, I will not have access to the informations on the original display.
Do you know were I can get one of this ?
The ballancing wires are correct wired with the good voltages values. Set of 40 cells, 36V, thats to say 10S4P assembly.

Thanks to all for your support.

 

[neptronix]

cells rusted? you have significant water intrusion and getting the battery to work will very likely involve rebuilding that battery and only using the case.

Given that this is a name brand ebike, it's very likely that you have a battery that's locked to the controller and therefore can't be replaced without some firmware hacking etc ( if at all possible )

Your safest bet is to buy another battery or BMS from Ducati ( if they sell it ).
If you can't do that, you need to replace: bms ( or just battery ), all wiring harnesses, controller, display, probably throttle, ebrake lever, PAS sensors, and anything else electronic that isn't the motor.

Hope some random firmware/electronics hacker finds this post and helps you!

Too bad this isn't a DIY bike; you'd simply be looking at a battery replacement from 100's of different makers if so.

 

[giles202]

"cells rusted? you have significant water intrusion and getting the battery to work will very likely involve rebuilding that battery and only using the case."

Yes, thats exctelly what I'm doing and I have the pack already finished.
The motor it is a usual gear front hub motor, so it is not difficult to override the system. But, in reality I would prefer to keep the same bms because they are 2 wires going to the display. I remember portapower had that kind of display too and they controllers with this feature. If I don't get, I will put one ordinary BMS and keep the display off. Let's wait if someone can add more info's about these "special" BMS. Thank you.