So everything works when on shore power but on generator only front AC works. Does your rig have ATS automatic transfer switch? This automatically switches power whether you are on shore power or on generator. If you do not have ATS, then in the compartment where your power cord is there will be a plug that you can put your shore power cord into. This plug is powered by the generator. So if you are on shore power the cord is plugged into the campground pedestal. And if you are on generator that plug is plugged into the receptacle inside the power cord compartment.
If that is not your situation, then make sure you check the generator itself. Mine has two breakers on the generator that must both be on.
Good luck. ronspradley
1993 Gulfstream Sun Voyager DP 30'
200 HP Cummins B5.9, 4sp Allison AT542
Toad 1998 Honda CRV, 2006 Honda CRV
Life's too short to drink cheap beer