Looking for a BMS for a Bosch PowerPack 400 Classic

[Andyver]

Hello everyone,

this is my first post on this forum and hopefully someone can help me. My mother has an older ebike that uses an old powerpack 400 classic. Now her battery died and i'm trying to fix it.

I'm pretty shure that the problem lies in the bms so i was wondering if anyone here would have a spare one? from another broken Powerpack?

https://drive.google.com/file/d/1CsaUD2j5em1ivGLVEk87I6aanfR6HwOV/view?usp=sharing

 

[amberwolf]

If the output has shut off, and wont' charge either, it's not usually a dead BMS, it's usually a BMS trying to protect you from a fire by recharging cells that went too low in voltage.

Some BMS's will even permanently "brick" the pack to prevent a fire, not allowing recharge even after the cells have been replaced. In cases like that, you *would* need a new BMS, too. But if the cells are not replaced and had gone too low, it's probably just going to happen again and brick the new one, too.

I don't know if your particular system is the type that requires the original BMS in order to run the bike, but some of them do. In those cases, you may have to replace the pack with another Bosch pack of the same type.


First, you can test the individual cell groups for voltage, to see if any of them are below LVC, and may be causing this probelm.

 

[Andyver]

Thx for the advice.. yesterday all the lights were blinking.. i think to tell me that the battery is slowly discharging. I got up this morning and all the leds where out. i think it's out of my control now .

 

[amberwolf]

What lights?

 

[Andyver]

The led lights that were blinking

 

[amberwolf]

Yes, you said that. But you don't say what LED lights those are. Are they on the battery? Or the bike display? Or the motor? or the BMS? Or the taillight or turn signals? Etc?

Without knowing what they're for, knowing they are blinking isn't useful.

 

[AngryBob]

HOW OLD IS IT AND HOW LONG DID IT SIT WITHOUT CHARGING?

Yes I am shouting because you may be dealing with a serious fire hazard.

If it does need replacement power pack, after you recover from the shock of seeing the replacement cost, you may want to consider a different ebike which avoids the evils of proprietary parts.