As it works on manual and not automatic makes me think it is related to one of the temperature sensors that tells the system how hot or cold the interior is. If it was the compressor it wouldn't work in either mode. The primary sensor is the one behind the panel under and to the right of the steering column. If it fails the controller thinks that it is cold in the vehicle and will not operate the A/C. There is also a sensor on the intake area of the HVAC case that performs a similar function but detects the air temperature inside the case to keep the system from freezing up if it's humid. In this case I would use a scan tool to verify the issue first and be sure that it isn't one of the other sensors, however if you just wanted to toss a sensor in they run about $20.00 or so which is cheaper than most places will do diagnostics for. That would be your call.
To access it you need to remove the lower panel. To start you remove the instrument side trim panel using a trim stick or plastic putty knife.
The panel is attached with clips and hooks, you use a trim tool to gently pry them loose
Broken square indicates: Metal clip Broken circle indicates: Pawl
Now tip the panel down enough that you can remove the sensor wiring and the sensor from the panel. Reverse the process to reinstall the sensor and panel.
Or have a shop run the diagnostic and see what it shows. As the system operates in manual mode it has to be an issue in the automatic controls, not the mechanical side of the system, something like a bad compressor or low charge would make it stop working completely.
Images (Click to enlarge)
Tuesday, May 25th, 2021 AT 11:24 AM