Waste tank level sensor: spontaneous remission?

Black tanks fill up slow. If you can look down and see how full, why spend money to fix it, esp since the odds are it will quit working anyways.

I have ignored my gauges for years.

BTW, you can buy a endoscope camera for a smart phone for $30 and a sprayer and probably get results.

Also, sensors conduct when wet, so will give false readings after driving. In a day or so, they may start working again.