Suburban Rear Air/heat

[sxmax]

I was only getting cold air through the roof vents. Read a post on here that the actuator motors go bad on the blend door and the heat-a/c door. I replaced both motors tonight because after removing the panel, no matter where I had the knobs, the position of the motors did not change. Well even after the motor change things did not really get better? Is there some type of re-learn from the climate control as to the position of the blend doors with the new motors? Is there something else wrong? Anything else I can check or need to know about the workings of this rear air/heat system? I have access to a pretty good scan tool but it did not read the HVAC codes or motor position in the BCM.. Please help...

[melchior]

I am trying to fix the same problem, I even replaced the rear heater core and it didn't fix the problem.