I have same problem
Brandon,I bought my Hunter 376 (new) in '97 and started to experience the same problem you have described within a couple of years. I have pulled the sensing units - not a pleasant job on the waste tank -- cleaned everything up, put them back in (and modified the gasket and attachment bolts - but that's another story). They worked for a while then did the same thing. I have given up. Today I just estimate when I will need a pump out or water fill. This method has worked for me. If I decide to install new gages they will definitely not be Wema's - product is totally unreliable and useless in my opinion.Ken