Test the mosfets whilst the controller is open with no battery power.
Set meter dial to 20k or 200k ohms and probe the Black battery wire at discharge pin against the three thick phase lines you can see on the board in front of the fets, one should see about 9k ohms for each one or at least they should be all fairly close in reading. Any way out of whack (very low) means a fault.
If ok then try again against the Red discharge pin you may or may not get a similar reading but an ascending one on all or may just a 1, as long as none are zero then thee will be fine on this side.
ok, if you can follow this image:
Green is the black probe (for clarity) to Battery negative (the black wire).
Red ellipse is where I put the red probe.
I get '000' for pins A1, B1 & C1 and '1 ' (see image below - as in the default reading when the probes aren't touching anything) for all the other pins (including D1).
I don't have a Battery positive on the BMS so put the probe directly on the red wire on the end of the cell pack (that goes to the case terminal). I get '1' for every mosfet pin doing it this way.
My multimeter only has 2000 ohm and 2000k ohm settings. I did it on both and got the same readings both times. For ref its a Altai DT830A (fairly basic)
