I picked up my 2001 Diplomat from the paint shop but have a problem.
Problem: Onan 7500 diesel Gen start switch on dash is dead – does nothing. Same with switch on the genset.
Coincidentally, the radio switch on the dash (right next to gen sw on dash) is also dead.
What I found at home: No 12v in the house: the 200 amp fuse for the house batteries was blown. I replaced the fuse and all 12v and 110v in the coach appear to work.
What I think happened: while at the paint shop, they left the key on and killed the chassis batteries (6 years old so not surprised). I delivered 2 new batteries so they could stop jumping it to get the coach started. While jumping or swapping out batteries, they caused a short somewhere and blew the 200 amp fuse. The new 200 amp fuse is holding.
I installed new house batteries when I got her home – took a pic so I know I’m spot on. However, I am not sure that they have the chassis batteries wired correctly. I was not allowed in the shop to do it myself.
If someone has a similar or same coach and can send a pic of what the chassis batteries and wiring look like, it would be a big help in troubleshooting. Below is a pic of how things are and they look correct to me. 2 different angles so you can get the whole picture.
I realize that if they have a negative to positive or vice versa, they possibly killed the mother board in the generator. I found a shop that can diagnose that, but can’t verify that the batteries are connected properly. There’s no sense in removing the genset, installing a new board, only to blow it again if the batteries are not connected properly.
All that said, if the batteries are connected properly and the board tests OK or put a new one in, what else could be the problem?
This is a totally foreign problem to be and so I have zero knowledge here.