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A 518/46RH trans only has a two wire plug for the OD. Power to one wire and ground the other. Its just a controll solenoid. It doesn't care which wire is hot or ground.
If your not using the PCM on your swap the TPS is not needed. That sensor feeds a signal to the PCM. The trans itself has no use for that signal.
To control OD just pickup a Hobbs adjustable pressure switch. Plumb it into the test port for the governer on the trans. Then adjust it to the MPH you want OD to come in at. The down side to this way of hooking it up is it will only go into OD at the set MPH. There will be no part throttle upshift. It will work if the main thing. Any time you would drop below the set point it would down shift to 3rd.
But the TPS has the ability to semi adjust shift points.
The PCM controls the OD shift. Without a PCM there is no need for the TPS. The solenoid inside the trans is a on/off electric solenoid. The TPS is nothing but a variable voltage signal for the PCM.
All the trans sees from the PCM is one of the wires going to ground to engage the soleniod. The trans has no idea it is controlled by a PCM. All it wants is a ground signal on one wire from the solenoid to engage OD. What controlls the ground doesn't matter. It could be a PCM or a single toggle switch or a Hobb's switch.
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