Error code 1603-underspeed

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Joined: Wed Mar 03, 2021 2:31 pm

I have a generac 22kw evolution home generator. It is natural gas with a transfer switch. I have it set to run for 30 minutes once every 2 weeks. Lately, I have been getting an error code 1603-underspeed. It is 1.5 years old. I can't seem to find any material on the solution to the problem. Does anyone have thoughts?
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Location: Clawson, MI

The first odd thing I notice is that these won't run 30 minutes for an exercise, only 5, and that duration isn't changeable.

The underspeed is telling you that the engine isn't running fast enough. That is usually fuel related or a stepper motor issue. When you put the unit into Manual mode, do you see the throttle sweep back and forth before it cranks?
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