2001 Tahoe - No Blend Door Activity

[corporal_clegg]

greetings. I lost control of hot/cold blending on a lengthy trip last week. after a little troubleshooting, I determined that my rear controls were functioning, while my temp selector for the forward zone was not. the heater core seems to be ok, as are the vent controls and blower speed. I determined that the Blend Door actuator was not functioning. I removed the old Blend Door Actuator and replaced it with a new part (Dorman). before installation I hooked up the plug and got no response with the ignition on and rolling from cool to warm on the selector.

is it possible that the blending control itself is bad?

can the computer be malfunctioning?

is the computer "brain" housed with the 3 controls on the operation panel?

please respond with any advice/answers/experiences with this sort of issue. thanks for your time.

 

[NJTahoe]

I had a problem when I replaced mine a while back. I tested the blend door actuator while it wasn't mounted and caused it to turn all the way in one direction and freeze up. I had to remove it from the plug and then open it and free it up.

When it is plugged in and you put the temp either all the way to the cold or all the way to the hot it will keep going in that direction until it either gets stuck on it's self of breaks the gears. Mount it before testing.