Chinook RV

All the switches to start the generator are suddenly inactive
Batteries are fully charged but nothing happens when I press on a switch...even on the one on the generator..
No breaker in the genny compartment...or elsewhere...

My Onan 4K generator does have a circuit breaker in it. The image below shows the manual switch, and right below it is a label pointing to the circuit breaker to its right (you can see the handle).
Another possibility is that a grounding wire under the chassis broke off and is no longer in contact with the chassis metal. That would mean there is no return path at all between the battery and generator, so the generator starter wouldn't do anything. Slide under the chassis and slowly work your way around all of it, looking for loose wires, broken or rusted bolts that have wires attached or near them.

Thanks for your input.
I don't have any breaker like the one in your pic or anywhere in the compartment or unde the engine hood.
I crawled under the Chinook & all wires seem ok.
Must be a blown fuse somewhere...but here in France they have never seen a Chinook or anything similar....so no easy help to be expected..

what year is your genset? Mine is 1999, and it has a 5 Amp automotive blade fuse on it.

There is a troubleshooting guide from Onan that can walk you thru the various test to see why the cranking motor does not work. You can also try to probe around with a multimeter if you have the schematic for the genset, which is available on the Reference section as well as on the web or via the Onan service representative.

Very good idea to check the Onan website.
mine is also a 99 but I see no fuse...
Will try pocking around with a multimeter....
Must be a simple fix...once I find the culprit

Check the house battery breaker switch undern the hood on left side.