Hi,
If everything were tight and in good condition, there could be a voltage issue to the actuator itself. The actuator receives voltage from the controller. Based on the request, different voltages are sent to the actuator for cooling. That is how the actuator knows how far to open. When you want heat, the polarity is switched to the actuator which causes the motor to turn in the opposite direction. How much of a difference is there between the two sides?
If you want to check the voltage signal, I attached the directions below. Note that you will be checking voltage to the actuator and not from the actuator.
The specs are at the bottom of the pic.
Here is a link you may find helpful:
https://www.2carpros.com/articles/how-to-check-wiring
Let me know if you have questions or what you find.
Take care,
Joe
See pic below.
Image (Click to make bigger)
Sunday, June 26th, 2022 AT 8:00 PM