The WOT circuit on the SC1000 is designed to be used with a contact closure switch, not a powered application like you've suggested here. In order to correctly log the release of the trans brake on that circuit, you would have to use the power from the trans brake solenoid to operate some type of a relay that would open or close the circuit.
As far as the switch connection on the SC1000 harness goes, you are correct; the switch simply completes the circuit, allowing current to flow and turn the unit on. By supplying 12v to both sides of this input, you are effectively "back-feeding" the system by introducing 12v power to the harness here as well as on the fused "battery" input on the harness. Since the unit sees 12v on the switch circuit, it will power on. However, this is not the recommended method, as your 12v supply coming in on the switch input is likely not fused and could potentially damage the logger and its components.
Let me know if you have any other questions.
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