We had the same "Return Levelers for Service" warning. Push both Enter and Retract at the same time and hold for a few seconds to clear the error message. In my case, the error message keeps coming back. We have had the control board and the sensor unit replaced. It is annoying even though the jacks work as they should.
2016 Thor Hurricane 35C with pups Piper and Annabelle
2013 Ford Fiesta toad
FMCA - F457085
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