Thank you !!!View attachment 48633After searching a bunch of threads here, I found my BMS had different ports. The two pins circled above turned mine on. 100amp / 4s / 12v recently arrived from China. So they must have changed the boards again.
Connecting the cables did not work for this BMS, and I spent an hour of frustration figuring it out.
Just received 4pcs of the same 100Ah 12vdc 4S Smart BMS's and same connector configuration.
First one turned on by connecting P- and B- and worked for 2hrs, went offline after I disconnected it from the battery (balance leads first)
Then it would not turn on, not shorting out the P- / B-. Not by adding a charge when connected. Finally threw in the towel, and
took the next one.
This one, nothing by shorting P-/B- or adding a charge (like lined out in the google translator paper that came with the shipment)(also instructions for a 16S bms, not the 4S version)
Now i was getting a bit upset and started to search here and there, as the bms's both showed 10.55vdc on pack + / bms P- so i tought it
was a bad balance lead cluster and replaced that one first, and no matter if balance leads were connected or not it showed 10.55-11.55vdc
but no current and the bt-dongle would not turn on.
Then I found this thread and your answer. Took a small screwdriver and shorted out hte opins in your picture, and voila! the bms came to life.
Thank you once more !
Now I can continue with my project.