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Please help! My board won’t charge


I already checked everything that everyone said
I just received the new charger I’ll try it and if that’s not it maybe the bms


If not the charger I might take it apart tomorrow hehe I just get tired of the show I work 7-12 so it’s hard to have time because when I get out I want to see my kids and new baby


It depends because I think @whitepony doesn’t use bms


Ok so it wasn’t a faulty charger and tomorrow I will take it aparte and inspect again the bms


Ok after this movie I will open the beast hehe



So what do I do know I already checked the bms to battery connections they are fine


Individually probe the balance connectors and check the voltages of the individual p groups


I checked each p group on the battery pack and that was fine


How do I check the balance cables ?


So p group is 3.247 I will check in a couple of minutes again



I checked what the charger is putting out. Also did you check the solder joint maybe cold solder joint.


So that’s from the cables from the charging por bms - and battery +


Same p group as before is 3.248 so I will let it charge for a hour and check it again


Your pack is fully charged.


No it’s un charge


Its a faulty BMS. The BMS is like a switch, when it detects that something is wrong or a group is fully charged it will essentially open the switch. The switch is for some reason not closing, either something wrong with the battery that the bms is detecting or the BMS itself. If you checked all the cell voltages on the balance leads and you checked the voltage across the battery mains and they match, the problem must be the BMS.

Where and how were you measuring each P group voltage? My recommendation would be to measure this at the bms xh connector. If the voltages here are fine, then the balance wires in the battery are fine. Pin by pin, the voltage should increase by a set amount, 3.25v I believe you said. Then check that against the voltage on the mains. The voltage on the outermost pins of the xh connector should match the voltage on the XT60 connector. If this is true, you can rule out a bad battery and it’s either a bad BMS or bad charger.

Given that, you already tried a second charger with the same results, the issue must be with the BMS. The BMS must not be allowing charge for some reason. Either it’s faulty or maybe it’s detecting the battery as over discharged


^ what he said


Ok so negative from the volt meter on the balance leads and where do I put the positive ?