BMS not charging. S-8254 reset

[Craiden]

Hey all,
I got a e-bike battery 7s4p where 3 of the total 7 serial Battery packs were discharged around 1V - 1,8V. I revived the cells and loaded with a laboratory power supply safetly to 3,5V to 3,6V each. All of the cells are holding the voltage since 1 week. The main problem is, that the BMS is not charging the battery pack.

There are two ic‘s S-8254A on the pcb.

I tried to read the documentation of it, but I couldn‘t find a way to restart the BMS.

What can i do to load the e-bike battery?

Multimeter, oszilloscope and more is available. Except an external cell charger.

 

[A-DamW]

I tried to read the documentation of it, but I couldn‘t find a way to restart the BMS.

Sometimes applying a charging voltage to the charging port of the bms will wake it up.

 

[Craiden]

Sometimes applying a charging voltage to the charging port of the bms will wake it up.

Thanks for your answer,
i have 2 of these on the board.
One for the first 4 cells packet and the second one for the last cells.
Where should I apply the charging voltage?.

Or directly on the ground and positive end of the total cell packet?

 

[fechter]

Apply it to the main red and black wires that go to the controller. You should get some charging current through there. Don't leave it on too long since there won't be any protection for cells going over voltage. After that, see if the regular charge port is working.

 

[Craiden]

Apply it to the main red and black wires that go to the controller. You should get some charging current through there. Don't leave it on too long since there won't be any protection for cells going over voltage. After that, see if the regular charge port is working.

Didn’t work.
I crashed one of my lab power supply before… forgot to install a diode in serial.
Lab power supply is after a repair running fine again. That’s the reason why my answer took a little bit longer than expected.
I have added around 27V on red and black batterie pack while it was either plugged on the BMS and without.
Back to main power supply, not loading

 

[fechter]

The BMS should reset itself when all of the cell voltages are within the allowable range. You can try measuring each cell voltage at the BMS connector to make sure all of the wires are good. If those look OK, then something on the board may have failed. In most cases, repairing the board is not practical and you should get a new BMS.