[RonS] I have the same problem, and I think all do if the unit is over a couple years old. I am waiting for others to reply to your post so I can try what they offer. I have added a number of cleaners but nothing worked so far. I have been told, but not yet given it a shot is to after flushing tank add about three gallons water then dump down a couple bags of ice cubes into the toilet and drive down a bumpy road. The ice bouncing around is to clean up the inside of the sensors by knocking off all the crud. Then they melt and all is well.
[john] It seems like the grey water tank has given me the most trouble and have had some success using different cleaners. I think the clue was to leave the tank partially full and travel for a full day. But it doesn't work long after that. Good luck.
[Jerry] This is to add to my orginal query. The type sensors that I have are taped to exterior of the tanks with al duct tape. I sort of got the feeling that some of the feed back was for interior type sensors. Thanks, yall
[Butch] Most sensors are on the outside of the holding tanks. The ice cube trick does work but dump it after you drive it. Cleans the tank up nicely. Better than chemicals and faster. Happy motoring, Butch.
[Jerry Groah] Have located webb site for sensors if they are made by Acu Gage.They have a webb site under the name of Snake River electronics. Their phone no. is 208-233-7290. This is their tech section. My contact was with Dennis. He was extremely helpful. Called by phone and discussed my problem at lenght. He advised calling above phone no. for further assistance. Jerry
[Chris Grangeaud] Butch!!! weren't you one of those who was ribbing me about this idea last year on the rvamerica website?!
Glad to see this idea is catching on. The ice cube trick really does work.