I have the same "high setting" issue with my A/C. We replaced the connector to the resistor because of all the burns we had seen on it. All wires soldered&heat shrinked and everything.
Also, replaced the blower motor and the fan resistor .
Our mechanic had stated that there is no power going to the "thick" wire. Ive seen everyone say to check if theres power going to it and there is not.
How do we even solve this issue without bypassing , or jerry rigging anything. I am not too good with mechanic work, nor electrical issues. But its really hot out now and our astro is our work horse and we need it fixed asap. Thanks