The 'n' display indicates that there's a problem with the control circuitry. Try resetting the control board by turning the fridge off, then back on again. If this does'nt solve the problem, go to www.rvtechlibrary.com, and follow the instructions for a 'hard reset'. If this fails, you'll need to have the problem diagnosed by a RV refrigeration technician. Most RV dealership have one on their staff.
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