ATS not working and looking for advice

[azpete]

sorry, but good information never dies. maybe someone learned something while reading. i know this is not a plato quote, but its true.
i just copied the diagram for future reference.
ive found loose wires many times. seems vibration loosens them.
this forum is the most useful source i have found in over 59 years of repairing rv's. there is always something to learn. when i stop learning, ill probably be gone and buried.

[Archer2]

Re my post #22 above, I think I finally understand what the OP was trying to say. It was that the ATS was supposed to be “generator dominant” but it was not switching if there was shore power connected. So anytime the 20 Amp shore power extension cord was connected, the ATS remained on shore power regardless of whether the generator was also running or not.
Is that right or am I still misunderstanding what the problem was?
And Travlin2, I’m aware that the problem has been fixed but I still had some questions. In my opinion the point of the forums is only partially to describe how a problem was fixed but also partially to learn something about the system(s).