The AC circuit breaker panel is the center and main distribution point of your RV's AC power system. If you are comfortable with working around (testing) AC power, then remove the front trim panel from your breaker box by removing the 4 screws at the corners of the breaker box front trim.
Do not touch any metal surfaces (especially wire conductors) with your bare skin. The best testing device is an electronic multimeter set to measure AC volts up to about 300 volts. Second best is a non-contact live AC voltage non-contact "sniffer" device. The power from the shorepower / or generator comes INTO the big mains breaker(s) on big wires, and is distributed on conductive rails underneath the individual branch circuit breakers, out the connect wires to the AC power loads. You can measure the voltage going out to the AC loads by applying the multimeter or non-contact voltage tester. Work your way from where you DO measure voltage to where you don't.
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