blend door problem on 2000 Buick Century

[billschillin]

IAfter viewing the posting here [ http://www.pontiacbonnevilleclub.com/fo ... ew&p=39609 ] concerning the blend door not opperating properly.
I located my blend door actuator and removed it and it is not broken. I can apply 12 volts directly to the motor and it functions ( spins the motor and transmission, reverse the wires and it reverses the motor. ) . I don't know if the potmeter is bad or if the sending unit on the dash board is bad. Is there a way to either test the line that plugs into the actuator for the correct signal or a way to test the actuator? ( besides using specialized or propriatary testing equipment) This is on a 2000 Buick Century, I know it is not a Pontiac but it is still a GM product and the procedure should be the same. I thank you for any advice you can offer ( I know I can go and buy an actuator then plug it in to see if that solves the problem but money is tight and I don't want to buy anything till I narrow it down more )