HVAC problem with 2001, blend doors not calibrating automatically goin into defrost default mode

[Whitelx1]

What started off as my heat only blowing on the face vents, now the system is in default.
I replaced the mode actuator with a GM one and tried to calibrate it and after installation it only goes to defrost.
I thought it might be a bad control panel bought one and now when you plug the new one in, it cycles thru all the cycles and Goes back  to default.
At first I was getting a BCM code of a aspritator only to find out mine was unplugged. I plug it in and now the code is gone but still only defrost...
Has anyone experienced this before. I am completely lost right now and I even had a friend from Chevy look at it on a GMscanner. He manually opened all the blend doors and when you shut the truck off back into default...

[Formulabruce]

Pulse motor is blocked, and trying to reset. Grab a cheap Scope for your smartphone and find out what fell into the defroster duct.

[vandenbroekjj]

I have a similar issue with hot and cold blend door if I pull the circuit breaker on the driver side it will work for a couple minutes then stuck in whatever it’s last position was.

What is the calibration method you mentioned?


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[swathdiver]

On 12/10/2018 at 2:08 AM, Whitelx1 said:

At first I was getting a BCM code of a aspritator only to find out mine was unplugged. I plug it in and now the code is gone but still only defrost...
Has anyone experienced this before. I am completely lost right now and I even had a friend from Chevy look at it on a GMscanner. He manually opened all the blend doors and when you shut the truck off back into default...

What BCM codes are/were you seeing and what kind of tool are you using to pull them up?