Yessir, I do happen to have a passing idea on that one!
We just lived off the power it was putting out and I did have to do a bit of looking at it at one point when I pushed it too hard to try to feed more things in my house than it liked!
A couple points to review is how you were trying to start as any engine starts best if we give it the best power we can, so I always try to start the RV engine first as that does lots of good things for the genset starting. When it's cold and I assume it may take longer cranking to start, having the Rv engine running lets the mode solenoid connect both battery strings together as well as lets the engine alternator push power to them, so you get a team of three providing power!
But then if it fails to crank, there may also be some cable chasing to do. This list will help ID which cable as they put different colors of tape at the ends to help ID where they go.
It sounds like you have already got a good handle on the issue but I might mention two things that are easy to overlook.
One is that there is a breaker on the genset, kind of hidden but I also think it is not on the cranking part but on the output so just something to know and file away, perhaps.
Second is that there are super big fuses under the plastic caps that might just look like a cover and one could be blown. The one I got a picture of is just behind the passenger side front wheel and there are some in the battery box. This one has blue tape to show it is for the jacks and not likely to be involved with what you need.
Beyond that, I have only seen the genset cable looks to go back to the frame rail to get to the front, but I've never chased it. Perhaps one of these big fuses along the path?
There is one big fuse which I have not got an ID on which might need checked but it is behind the breakers on the drivers side and near impossible to get to without taking the breakers loose to get behind them.
Click the schematic drawing to read it better but it does show a fuse and it is located next to the disconnect relay where I also see a fuse on the parts drawings. Does that mean it is the same fuse? "MAYBE" ?
Red item is mode solenoid, purple is disconnect relay and the yellow?
But if you chase the cable from the back and find it going into the box there?
Linear Mode
