06/10/2026
Before going on your trip, if your RV or camper has a gas or LP generator, make sure you start it and let it run for at least an hour or more under a load (ideally once a month when in storage or not in use). If the generator won't start up right away;
1. are your 12V batteries fully charged and is the disconnect switch in the off position? If they don't have enough voltage, it will not start.
2. If yes, but nothing, do you have enough fuel? Less than 1/4 of gas, typically won't allow them to start either, or if the gas is old and may have sediment or debris in it.
3. Have you checked the oil level? (some generators will not start or will try to start and shut down if there isn't enough oil)
4. If it runs and there isn't any electricity being produced (you can check the microwave), are the breakers on the generator off or tripped?
5. Also, on older coaches the 30/50 amp cord had to be plugged into the unit to provide the camper with power once the generator was running.
6. There is also an Onan Troubleshooting guide that is free online that may also solve some of these issues and or others as well as YT videos.
If you have checked all of these above and are still having issues, you may want to contact an RV dealer that services Onan generators or other types of generators.
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