Faulty black water sensor

they rarely are correct, stuff sticks on them an they don't read correctly. Look in the hole to see how full.

Common problem usually the result of toilet paper debris getting caught on the sensor probes. Many just ignore the sensors and just look down into the toilet to judge how full it is. You can purchase a Flexible tank wand which can be used to clean the sensors. Visit Youtube there are plenty of vids that show how to clean the sensors. Some will replace/upgrade the OEM sensors with sensors that are less prone to getting crud on them - many don't think it's worth it.

Check out SeeLevel Gauges. A different type of level sensors. I've put them on our last two mhs.

Dusty

Mine rarely work correctly either; What I do is turn the water pump off - then hold the toilet flap open and peer down to the tank with a flash light. You may need to keep air freshener handy ..

X2 on the SeeLevel II tank monitor system. I much prefer the more accurate percentage readings over the typical "Empty, 1/3, 2/3, Full" setup. And the external sensors are easy to install with reasonable access to the tanks.

For some time Winnebago has been using their version of the SeeLevel system. While it does not have the digital readout (only gives 1/4-1/2-3/4-full), it does have mass sensors mounted on the outside of the tank rather than the through the wall pins that get fouled by tank debris. Do the GEO method with a small bottle of dawn and calgon water softener. Fill your black tank 1/2 full of water and drive some curvy roads to slosh things around. With luck that will clean off the sensor and get your monitor working again. Best chance to keep it working is to never dump the black tank until it is almost full and be sure to dump 2 bowls of water after each "deposit" in the toilet. Lots of water is your friend. Makes for a more forceful dump that is more likely to carry stuff off the sensors.

As stated above, the sensors on the holding tanks very seldom work right. Maybe the first day after being shipped from the factory, but after that, it's anyone's guess.

Reason? Stuff sticks to the sensors giving a false reading.

The solution is really simple however. All you need to do is dump your tanks completely. Rinse them out by adding a full tank of water via the toilet and dump. This cleans out any excess stuff that did not get dumped out initially.

The next step can vary, and maybe do all of these procedures.

The simplest is, now add about 5 gallons of water to the black tank, a bit of dish washing Liquid to the tank. If you want it to smell better, add a cup of bleach, and take the camper for a 20 minute drive over bumpy and curvy roads with lots of stops and turns. This will slosh the contents of tank around, sloshing and cleaning the stuff off the sensors.

When you get home, or your next camp site, drain the tank. You don't want the bleach sitting in there long term. If yo don't use bleach, dish washing liquid won't hurt anything.

Now, if you can't drive, or even if you do, there is an alternative. Assuming your black tank does not have a black tank flusher attached to the trailer, get a toilet wand from any local RV shop or even WalMart. Attach it to a garden hose, shove it down the toilet, turn the water on, and spray the dickens out of the tank, letting it drain as you do. The high impact of the water hitting those sensors, and the inside of the tank, will pulverize anything left clinging to the sensors.

The sensors will work again correct (but only for a while). So the secret to keeping them working is to empty all the contents of your tank before hitting the road every time. Then add about 5 gallons to the tank with a bit of dish washing liquid and drive to your next destination. If you do this (without the bleach), not only will your tanks stay clean, you'll never have smells, and your sensors (should) work.

If your camper is stationary, then use the toilet wand on the garden hose after ever few dumps, or you notice the sensors not working correct again.

This is the least evasive, an in my opinion, the best way to keep the sensors working AND the tank clean.

If this does not work, then there is something wrong with the sensors. If that is the case, then consider switching or replacing the sensor system as suggested by the above posters. No need to spend money yet. Try it, see what happens.

Assuming this is a new camper for you, in time you'll quit using the sensor readings completely. Why? Because in time, you'll know how much water you can use, and as you get more familiar with the camper, it just becomes second nature to keep a mental track of how often things get used, especially water usage. You'll just know when it's time to fill the fresh water tank and dump the holding tanks.

As far as the black tank goes, most camper have the toilet with the foot pedal and the slide valve in the bottom of the bowel. Every time you push that pedal, you can look down the hole and see how full the tank is. Here again, it takes a few times to learn it, but it does happen.

I very seldom use my sensors any more, but after 5 years of owning this camper, the original factory sensors still work. I attribute that to towing the camper with little water in the black tank and the dish washing liquid. And I actually tried them last night, and still work (showing empty right now, which it is.)

It is not the “sensors” they are working just fine. It is the scum or debris on the tank wall between the “sensors” that carries the current. If the bolt, called a sensor, is covered with an insulating material the light(s) would not come on. Clean the tank wall somehow and it will work for a short period of time.

I always use a tank wand when dumping and have never had any problems with my sensors. Knock on wood...