you might check your error codes.
Right after a failure the lights will flash.
or You can check the last code by pressing the off button three times.
the light will flash 3 times, then press the off button once.
it will flash a two digit code
as in
one flash followed by three flashes for "13"
the light is on the switch right on the generator itself. Mine also flashes the "run" indicator light inside by the remote switch too.
The codes are listed in your manual, look here...
http://power.cummins.com/sites/defau.../F-1123-EN.pdf
Honestly, I've not learned much yet from the codes the times mine has faulted, but maybe it'll help you.
Oh, couple other comments
My genny lately has been faulting in the heat of the day. It runs fine other times, so I'm thinking a cooling issue. Apparently somewhat common
Generators are plumbed so that it won't pull down your MH's gas too much..... something less than a half or maybe 1/4 tank and the genny won't work.... so you have enough gas to get to a gas station!