My PIR sensor has two yellow potmeters both labeled 105. Just like this:
The right one seems to kind-of change the sensitivity. If it’s rotated 100% clockwise it seems to work as expected. The out pin is high when movement is detected. Rotating the potmeter just a tiny bit back counter-clockwise makes the sensor to sensitive, the out pin is always high no matter what.
This doesn’t make much sense to me.
I have no idea what the other potmeter does. Seems to do nothing really.