Ah. Thought strikes
Normally the 120 volt power lead is one continuous run of Romex from the Breaker box to the A/C (however there is no guarantee)
Now rodents love to chow down on romex but I'm inclined to think not
Two issues I have personally seen.
Bad connection.. A/C end of cable (Where the Romex connects to the Flexible wires in the A/C) they often use wire nuts and ... Not the best connectors.
Check for any evidence of arcing or burning NOTE THIS can trip breakers both on the RV's breaker box and the outlet feeding the RV.
Other thing I've seen.. Joke. sort of. many RVers have a few screws loose.
When my rig was New (less than 1 year) I had major A/C issues. Sometimes one worked, Sometimes the other.. both or none.. Ok so I started at the breaker panel.. Noticed when I was pokeing around (Safely.. I'm trained in that kind of thing) wires MOVING in the clamps.. Uh. That's not right.
one screw took a full 3 1/2 turns before I was happy Others took over 2 full turns) Yup they stuck the wire in but never tightened it down.
