This 2001 Dodge 1500 Pickup came in with a complaint that the a/c would blow cold for about 30 seconds and then it would shift to full hot. I started with inspecting the temperature door actuator. It is located under the passenger side of the dash near the transmission hump in the floor board. I turned the key on and set the temperature at full cold while watching for the actuator shaft to turn. To my surprise it started turning and never stopped. I knew that was not right so I removed the actuator expecting to find that the door, inside the a/c heater box would be broken. Thankfully it was okay.
What I found instead was that the plastic adaptor was broken. Why did it break? Was it just normal fatigue or something more? Turns out it was something more the motor is supposed to have electronic stops built into it and that function was gone. I decided to also install a new actuator.
With the old actuator removed, I aligned the new adaptor on the door shaft and pushed it into place. I also reached on top of the box through the glove box opening (I removed the glove box assembly) and pushed down on the door shaft while pushing up on the adaptor. I also was rotating and wiggling the assembly until I felt the adaptor fully seat into place as shown below.
I slid the actuator into place and lined up the door shaft and then rotated the actuator housing until it lined up on the alignment peg. With every thing lined up I installed the front (easy) mounting screw.
Then I had to be creative and I used a combination of several tools and finger tip coordination to install the difficult rear screw. I put the phillips bit in a ratcheting wrench, slid it into position, held the bit in place with a small screw driver and rotated the ratchet until the screw was tight. It took several times of trying until I got everything aligned just right for this to work but it beats several hours to remove the box assembly or doing and incomplete repair. I used the same procedure when I removed this screw during disassembly.
These are the tools I used to install the rear screw.
