Holding tank red light

[olygirl]

Frequently the red light on the holding tank comes on when we know the tank isn’t nearly full. It happens when we are at a dock so it’s not because we are cruising and stirring things up. This is a problem of course because the system locks after 5 flushes and we can’t use the head. We flush with water every time we pump out and use a cleaning solution. Anyone else have this problem and does anyone have a solution…other than doing a pump out?

 

[dbsea]

Sounds like a sensor problem. Have you checked them to make sure they are still attached to the sides of the tank in the right locations and the wiring is still all good?

 

[olygirl]

No we haven’t done that. Wouldn’t know how but I’ll see what I can find out, thanks!

 

[dbsea]

If you have a Tecma electric toilet, you'll find two rectangular sensors attached to the exterior of your holding tank, one yellow (50%) and one red (full). They are attached with wires that run to the toilet/controller to enable the fill indicator and stop the unit from flushing. It sounds like one or both of them could be experiencing a problem, that's the first thing id check! here's a photo of what it looks like on my C30, from my survey:

https://1drv.ms/u/s!An3QgiOrn39pqWOQuMJ ... i?e=SsBzkC

 

[olygirl]

Thanks so much for the replies! Problem has been solved…there was tape left over the sensors that should have been removed and that was causing the false reading. We’re good to go!!!

 

[GarryH]

Thanks so much for the replies! Problem has been solved…there was tape left over the sensors that should have been removed and that was causing the false reading. We’re good to go!!!

I realize this is an older post, but I would like to ask if the tape referred to in the reply was tape on the adhesive side of the sensor? Thank you.

 

[OlygirlNav]

During boat build tape is placed over the sensors on the outside of the tank. The tape was not removed causing the tank sensors to read incorrectly. Since the tape was removed no further false readings.

 

[watson1987]

My sensors seem glued/epoxied on, they never register that the tank is full, I always just get a green light.

Has another seen that before?

I've cut the wires and the toilet light turns red, so I know they are connected 🙂

 

[American Flyer]

My sensors seem glued/epoxied on, they never register that the tank is full, I always just get a green light.

Has another seen that before?

I've cut the wires and the toilet light turns red, so I know they are connected 🙂

Mine is always green. Useless.

 

[watson1987]

My sensors seem glued/epoxied on, they never register that the tank is full, I always just get a green light.

Has another seen that before?

I've cut the wires and the toilet light turns red, so I know they are connected 🙂

Mine is always green. Useless.

Maybe you have the same problem as me then, the sensors aren't able to penetrate the tank to see the level

I'm tempted to try and buy new sensors and splice them in, but it would be annoying to spend $150 without knowing that's the fix

 

[American Flyer]

I am resigned to just living with it as we pump out on a regular basis anyway and do not have a problem not having an indication. But if you find a fix that works please post it here.

 

[kpfn1216]

Has anyone else ever checked what "full" looks like on their black tank? Here's a photo of mine (2022 R29) at the level where the red lights turns on. There's clearly a good half of the tank left unused (I'm lighting from the side, so you can see the level as the darker area inside the tank).

Curious if there's a good reason for this, if it's a mistake, if something is miscalibrated, etc.