That board will not support PWM. It has a 10k resistor on the gate
tlisek:
I've checked all the connections on board and made a schematic. The transistor turns on and stays on all the time (It's off only when my PWM duty cycle is at 0%), not changing the brightness of my LED.
That's not a working circuit. You have made a mistake as the gate is permanently clamped at the negative
rail and thus the MOSFET must always be fully on.
Also the resistor values are way too high for PWM to be possible - this could explain the behaviour
you see.