My blend door actuator on 99 chevy blazer only turns one way. (opens door for heat and cold air). I changed out my blend door actuator twice and the computer climate control is new. With the blend door out of the dash and still plugged in it just turns one way. I keep changing the temp, but the actuator just goes clockwise, then stops. Both of these parts are brand new. I don't know what else to check. Can anyone tell what else could be wrong? Is there anything else you think that might need to be change, that could cause this? I'm not very electrical.

 

same problem here

 

If anyone has figured this out, it would be great to know!

 

The computer climate control when power has been lost for awhile will do an initialization of the position of the blend door. This can only happen when it is installed.

And note that there are different blend doors depending on if you have a manual or computer controlled climate system.

I've attached scans from my 99 service manual that describe the initialization procedure.

 

Mine seems to get colder air on the TWO ARROWS setting vs AC or MAX AC.