Kitchen gray sensor always shows empty?

[MojaveJoe]

All of a sudden this summer, my kitchen gray tank sensor lights quit working. Even when the gray tank is full the light shows empty. The other sensor lights for the shower and toilet operate properly.

I understand how toilet paper stuck on the sensors in the black tank can cause it to show fuller than it is. But could grease etc also cause this opposite problem in my gray tank?

Any and all suggestions of what I should check appreciated.

Thanks,
Joe

[MojaveJoe]

All of a sudden this summer, my kitchen gray tank sensor lights quit working. Even when the gray tank is full the light shows empty. The other sensor lights for the shower and toilet operate properly.

I understand how toilet paper stuck on the sensors in the black tank can cause it to show fuller than it is. But could grease etc also cause this opposite problem in my gray tank?

Any and all suggestions of what I should check appreciated.

Thanks,
Joe

[450Donn]

dead sensor probe or a broken wire would be my first guesses.

[Ray,IN]

As Donn says, check the probe for voltage first; there will only be voltage present while the button is depressed. Use TSP cleaner in your tanks to clean them out. Dissolve the appropriate amount for your tank in a gallon of hot water, pour into tank, then fill to 3/4 (ya you gotta guess) with clear water. Drive around (or to your next nights stop) to slosh the cleaning mixture in the tank, then allow to sit overnight - if practical.
If you're considering upgrading to a reliable tank monitoring system: See-level gauges have a good reputation in the RVing community.