A/C Actuator Motor Calibration Shortcut Topic is solved

[jimmy57]

The potentiometer resistance measurement assures that you are on the right flat on the square shaft. The motor has internal stop for 180 degrees travel. On at least one of the locations the damper motor is used the needed travel is less than 90 degrees. It is possible for you to move it for that and other locations where it will fit but will run to travel stop or not be in the pot output voltage range. The pot can be measured via those pins to allow it to be moved with the 9v batt and get it in the correct place to assure you do not install out of phase.

[RickHaleParker]

That sounds like setting a Datum (a fixed starting point of a scale or operation).