Apologies, but I suspect my piccy is drawn a bit wrong there.
I just rechecked, and R4 is only 10 ohms so registers as "connected"
when i do a continuity test.
Basically, the outputs from the mosfets go to the pins on the 2 pin motor header.
Between these 2 pins is an RC snubber made up of R4 and C3
that sits in parallel with the motor
( I know these as a "Zobel Network" from loudspeaker designs )
As such, you could do a test to see which ends of R4 connect to C3
The other ends of R4 or C3 must then connect to the header pins.
Do a continuity test to see which is which, but beware, look for a true zero resistance
dont just rely on the beep ( like i appear to have done )
Andrew Johansen Melbourne Australia