Ok, I have a Ac unit that has gone out. I have changed the selector switch, since it would not cycle from off to high, still want work. I have swapped the relays under the good, nothing has changed. How can I test that the blower fan is working and maybe someone can tell me how to change out the controller unit, I havent seen anything here that explains that. The I can get back to replacing my compressor, dryer and hoses that is going out.