Black/Grey Tanks Not on Panel 2023 Micro Minnie 2018TB

[kdluke]

2023 Micro Minnie 2018TB
Has anyone experienced the grey and black tanks not registering but the fresh tank registering properly? The monitor panel of my 2023 Micro Minnie 2108TB does not register grey or black readings, but the fresh tank works properly. This has never worked from the time I picked up my trailer new from the dealer. I have taken it to the dealer twice for this issue. I waited months for a new panel. they installed it. I tested it on my next trip and it still did not work. I took it back to the dealer and they kept it for a few days and said it worked. I took it home and tested it and it still did not work. This is my second Minnie the first one had the small white panel and it worked perfectly. I am resigned to try to repair it myself. any help is well appreciated!
Thanks,
Ken

 

[Wmlunt-WO]

We have the same issue, but find that now the fresh is not reading correctly. Black and grey are intermittent. Not sure it is worth ripping the underbelly apart for this and sure don’t trust the stealerships!
Bill

 

[kdluke]

I agree Wmlunt, not worth ripping into the underbelly covering. I think we may have a ground issue. Intermittent issues most often involve cabling. I guess the next step is to get a good wiring schematic. my dealership said they replaced the panel. I'm done with the dealership.

 

[PFoss]

Had the same issue on my2014 vista 27n . Tried everything to get them to work. Ended up when I let the gray tank fill enough, it registered.

 

[Wmlunt-WO]

I guess chasing the ground wire fault may be worth a shot, but unsure if it is just stuff on inside of the tank.
I don’t have a good answer as to the type of sensor, probes on the tank or sensors on the outside.
Seems like my tanks are pretty darn clean, just barely 1yr old. The fact that fresh tank is not reading may be a conductivity issue???
Anyone know what sensors are used on MM 2108 fbs, 2024 vintage?
Thx! Bill

 

[reeman]

With the black tank at least one can see the level simply by opening the rolling toilet valve. Hopefully not with a gas mask on. Every year after winterizing it takes a few days for the toilet and gray water to register correctly on our rig. Kind of like a sensor float stinking in place and after having some water load and us walking up and down servicing and spring cleaning the trailer the floats drop down and start to register correctly that the tanks are indeed empty. Then what I do is use the right treatment with about 1/4 of the tank filled and take the unit out for a run then come home and fill the tanks and take it to a sanidump. The process of sloshing a small load around is better than just leaving the tank to dry out as almost certainly the float sensor will stick as any residues left in the tank at the sensors harden. Do not use chlorine bleach in the black water tank along with hydrochloric acid or other acidic black water treatments. One certainly does not want to turn their rig into a gas chamber on wheels by accident! Treating the fresh water tank with one cup of chlorine bleach to 30 gallons of water is a good idea and should pose no issues in the grey water tank but may corrode an electrical heater element if too strong. So what I do is bypass the hot water tank temporarily when chlorine treating the fresh water tank and only rinse the lines not the hot water tank with mild bleach. Aluminum does react to chlorine so hot water tanks can be problematic unless rinsed separately from the fresh water system. Most trailers do have the capacity to bypass the hot water tank for that very reason.

As I have stated the issue with false readings on both the black and gray water tanks is a common one and not a serious one unless the sensors fail completely and then it is back to using old school dip sticks because pulling waste water and black water tanks is a royal pita on most trailers. Some do have sensors that can be changed without dropping the tanks though so that is worth looking into. So far all I have had to do is change the dump valves which is normal and not that hard to do...touch wood that I never have to change the tanks themselves or re plumb the waste gates as happens with trailers that are badly neglected and have the sewage and gray water pipes split in winter!

 

[Wmlunt-WO]

Ken, do you know the type of sensors on the MM 2108? I am curious if they are probes, or sensors on the outside of the tank…
Anyone know of something to add to the tank to increase conductivity? Just a way of checking probe or the circuit electronics.
If it is junk on grey or black tanks wall I guess I could try the ice trick to try to clean the walls…
Thx! Bill

 

[reeman]

Turns out that your newer trailer most likely trailer has electrical contact sensors. Sorry about the misinformation. I checked my tanks and sure enough I have the electrical plug type sensors. There is a ground wire on another lead separate from the three level sensors on each of the tanks, it grounds to the frame of the trailer.
We do not do the ice trick on my trailer's blackwater tank because I know it does not work and is internet nonsense. We do use black water treatments down the toilet and use just plain old dishwashing liquid in larger amounts with a full grey water tank to clean out any grease or food residues in that tank.
Our sensors work, but sometimes do stick for a few days but never stick and not go back to reading tank levels at all. One tech that advised me when we first bought the trailer said that most RV water sensors that read either 2/3 or full all the time are just dirty and the tanks need to be filled and treatment liquid needs to be added to the full black water for at least a good few days before doing a sani dump. The grey water tank just needs to have liquid dish soap put in and then filled with warm water and again left to remove grease and food waste which usually causes the gray water sensors to give the false readings.
I followed that advice and even though they are at times still flakey they do read correctly most of the time.

 

[Wmlunt-WO]

Not sure what you mean by “electrical contact sensors” probes sensors typically measure conductivity to measure the depth of the surface in the tank.
The newer sensors mount on the outside of the tank and use capacitance.
Anyone know what type are used on Micro Minnie 2108 (TBS)???
I have a feeling they are capacitance type sensors and don’t know why they don’t read. 1 year old and religiously use tons of water, calgon beads and pine-sol for additive..
Thx! Bill

 

[reeman]

Here is the type of sensor that I was referring to. Either way one would think that a Winnebago dealer would know the systems. With these type when the water level reaches the exposed conductor it causes a difference in voltage enough to trigger the electronics into turning on a very low wattage led. Yes the new sensors that have a strip that adheres to the tank on the outside works a little differently. Nothing magic though just elementary electronics, fortunately one does not have to worry about a flakey computer interface that can call home or send out bluetooth signals if the toilet or gray water is about to overflow. But no doubt that is what will occur soon so that the price of fixing things will become greater then just trading in the unit, like many do with automobiles!
I would check carefully to make sure that what ever you are using to treat the tanks is not causing exposed ends of through the tank type sensors to corrode. If you do have the external strip type that uses tank capacitance to read water levels then I cannot think of why it is not working other than possibly a grounding fault of a single common ground wire for all the sensors.

 

[Wmlunt-WO]

Thanks, but don’t think RV’s are disposable yet.
The calgon beads/pine-sol is well known RV septic cleaners suggestion.
Would luv to hear from other MM 2108 owners if they found ground fault, and where…
Unwilling to rip apart the coroplast to look, and it may be stiff on inside..