E-bike Battery is 42v chargerd but there is 0v power to the outlet and charging port

[Drajko]

Greetings guys,
I am new here. recently i got an second hand E-bike Riverside 500e aaand the problem is, it cant be turned on. there is nothing on the display. i checked all the display cables, watched few viedos of similar problems but I couldnt find anything similar to my problem. I think the problem is in the battery. there is no power to the charging port and the outlet. I charged tha battery for more than 4h (it was 50-60% chargerd before I started charging it)its full now and after that I checked the voltage of the battery on the BMS( there is picture of the multimeter) and its 42v~.I measured every baterry block separately and they are aprox 4v~ each. there is no fuse anywhere exept one soldered on the board (40A) but its working properly. indicator is working fine (the diodes are not blinking) and now i have no idea what to do. there was post saying it could be from a dead cell, and i measured all of them(without removing it from the circuit) and i couldnt find a dead one. is it possible to be a dead fuse somewhere on the board that i cant find ? please if someone could help we i will be very greatfull.

 

[docw009]

How many wires connect the battery to the bike? Are there just two, power and ground? If there are more, there may be some communications between the battery and bike needed to start the battery. That gets into some bigger issues.

If there are only just the two power wires, then it's probably a BMS issue. Did you charge it thru the charge port or direct to the cells?

 

[Drajko]

I am adding some pictures(sorry for the quallity) on one of them is shown the connector port and on the other are the wires connected from the connector to the BMS. Is there anything on the bike that could stop the battery voltage going trough? i didnt checked the controller of the bike itself.?

 

[docw009]

I am adding some pictures(sorry for the quallity) on one of them is shown the connector port and on the other are the wires connected from the connector to the BMS. Is there anything on the bike that could stop the battery voltage going trough? i didnt checked the controller of the bike itself.?View attachment 359939

This must be the connection to the ebike. Are those tiny wire connections in slots 2 and 4? Is slot 5 empty?

 

[Drajko]

yes those ary tiny conections and yes slot 5 is empty

 

[docw009]

The small wires says that there is data shared between the bike and battery. You've done everything right on the battery checking the health of the cells, but the bicycle controller isn't letting the battery power up. I have no idea what kind of data is wanted here. Perhaps there are thermal sensors.

With these extra complicated proprietary systems, you need the manufacturer's documentation to diagnose them. WIthout that, it's just guessing,

 

[Drajko]

i thried something else. i have another 42v battery from electric scooter and i disconnected to positive and negative wire from the original bike battery and connected it to the scooter batery. only the positive and the negative wires nothing else. i disconected the connector that is wired to the BMS of the bike battery .... aand there is 42v on that big connector going to the bike controller. aaand everything worked fine with the scooter battery. i guess the problem is in the bike battery.... i cant be shure but:
Next thing that I observed is, when i touch the big transistors with my bare finger the voltage starts increasing. i guess they are sensitive to resistanse that i create with my finger but i dont know why is happening. is it possible to measure an element or something... i am a bit confused

 

[Drajko]

Another strange thing that i noticed is, on the marked transistors pins there is 0 voltage. On every onther one there is 42v~ . is it possible a dead cells to interupt the voltage to the transistors? its very strange. do i need to change those two?

 

[Drajko]

i still need help and i cant figure out what the problem is

 

[docw009]

Have you proven that all you need to run the scooter is 42 volts? The display turned on and the scooter ran with you sitting on it?

If that is true, you could install a generic BMS for the first battery and run it that way.

I don't advise changing out parts at random on a surface mount circuit board, or making judgements about what happens when you touch something, You would need a parts list and schematic diagram to fix a BMS,