Yo whats up guys.
I studied 2 books about electronics thoroughly. I thought i was done. Turns out that im still a pathetic beginner. A friend just asked me to repair his electric scooter. Because he cant charge the battery anymore. And frankly I have absolutely no idea what is causing that.
The battery i tested is half discharged. Normally the charger should go from green to red when plugged in. It stays green. I switched with another battery because maybe it could have been the bms. Same thing. At one point though the charger turned red. When i pressed the black wire with my bare finger. This doesnt happen if i press the wire wearing a glove. So anyway it turns red 2 sec then turns green again. I tried with an old charger and this one didnt turn red at all. So im totally lost. Btw this turn red quickly even when using another battery. I hope i made myself clear. Any idea whats happening guys ?

 

If the socket the charger plugs into has three pins make sure that thesocket is completely dry in side. On mine even a little moisture will kill it. I have no idea whether yours is the same.

 

thanks but I connected the wires of the battery directly to the charger. to eliminate the possibility of the socket being the cause.

 

I'd suspect a poor connection inside the battery to one of its terminals.