Grey and black water indicators wrong

[Stover999]

Our grey and black water indicators are incorrect. When we flush the tanks they stay the same. Are there sensors that need cleaned or something? Any assistance is apprrciated. Thanks in advance.

[JFlightRisk]

The OE sensors are inherently inaccurate due to their design. The inside head of the sensor is close to the tank wall, and anything can easily stick to them and complete the circuit to the ground sensor. Our black tank sensors still work ok. primarily because I flush it out with a wand down the toilet every outing. The gray sensors aren't easily cleaned, and were replaced with Horst Miracle Sensors after eight years, and starting to read 1/3 all the time. You may get some satisfaction from a tank cleaning chemical.

[dxrobertson]

As @JFlightRisk states, they are not accurate after minimal use from the factory.

With the black, learn to listen to the water being dumped into the black tank; when level is low a hollow deep sound, when getting full a more backing up gurgling sound.

The grey sensor tends to work better at/near the upper full level, less accurate with lower level.