joealackness

My sensors read full on my gray tank. I was at a RV dealer and asked about replacing the sensors. They had new sensor for $.65 each. (The old ones were glue in and could not be removed.) I replace them and the tank still reads full. How does the system work electrically? I would think that there is a positive to the system and the sensors are ground. Joe Alackness 2008 Forrest River Charleston