Hey guys, I've looked into all of your feedback and have made a couple of changes and am going to try another one based on my findings.
I ran into another post that was getting high readings. It basically said to try a pulldown resistor, which I understand to mean that it leaks current to ground from output of the PIR sensor.
What I'm noticing is that in the very moment either the 12v ground or voltage wires are connected, the PIR immediately goes high (with the PIR well protected from motion). I won't pretend to understand why. If that is making the PIR output too high, then a pulldown resistor makes sense (am I thinking about this right?).
from the other forum:
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when it detects nothing , it shows ON ON ON OFF OFF OFF ON ON ON OFF OFF OFF
... I would guess that my guess (!) was right...
The device probably is okay to pull the Arduino input high, but it is not "sinking enough current" (to use the technobabble) when in the low state.
Try the pull down resistor, and all may be well.
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