[Rich Biebel]

Bob.....I work on these units a lot. They often do random shutdowns and the code sometimes helps and sometimes does not. I usually work on the larger commercial version of what you have but they are similar.

Check the battery positive connection post. There are multiple wires landed on there and if the lower section is loose it can cause a shutdown. That is where the A-1 controller gets it's DC power from.

The A-1 controllers usually last a long time but sometimes one will fail when the unit is nearly new.....like the one I did today. If yours has 750hrs on it....the A-1 is probably still ok.......and your issue is something else. That is just from past experiences.....Most controllers last thousands of hours.

Brushes can wear uneven and cause shutdowns.....Easy to check....


I can help you or anyone that has Onan issues. I have been working on them and lots of other electrical equipment and machines for many years. I kill time amusing myself reading posts on here during the day or at lunch.....some very entertaining stuff usually in the S/SS area....

My self and my friend and service manager at work, Matt Schurman, race and work on these things just about at every race we go to. I have 3 M-H's right now here in my lot.......