# Waste Tank reading faulty



## gemmerson (May 1, 2005)

E769 is showing waste full when its empy. Anyone know how to access the wiring with the sensors/sendors on the tank so i can try and fix it. I know these things are prone to faulty readings..... but its an easy fix, i just cant find how to get at it.

Thanks


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## Mrplodd (Mar 4, 2008)

Almost certainly the waste tank gauge is simply a float switch. If you crawl underneath you should find it simply pushed into the side of the waste tank. It has a couple of wires coming out of it would should help you to locate it.

The thing will simply pull out (held in with a rubber grommet) The switch itself is simply a float that is hinged, when the level rises it lifts the float up, it pivots around a point and closes a circuit to show you it's full. Fatty deposits in the wate water "clog" the hinge part so the float doesn't !! That's why you don't get a reading. It's very simple to fix ONCE you have actually located it in the first place. 

Andy


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## Geriatricbackpacker (Aug 21, 2012)

Just in case it's not that type as ploddy has described (sorry don't know vans have what systems).

On mine I believe they are prong type (gives 5 readings empty, quarter, half, three quarters and full) and it is not easy to get to. I bought a bottle of Tesco's cheapest liquid bio detergent (the sort we use for the toilet) tipped it down the sinks and shower and then poured buckets of hot water down them until I felt that the tank should be full (about 100 litres). I took it for a drive and then left it for a while before emptying, the gauge dropped as it should. As a belt and braces exercise I put a packet of Tescos anti limescale treatment into the waste tank by mixing it in a couple of buckets of water and ensuring it had dissolved and then left it overnight before emptying.


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## deefordog (Dec 31, 2013)

On the Kontiki 6??/Bessacarr E7?? models, the sender only has two probes, at least the fresh water one does. Will have a look around ours later to see if I can find where the waster sensor is located. This will be something I need to look at anyway.


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## GMJ (Jun 24, 2014)

Measuring water levels in my Comanche are like a lottery tbh. I get 25% full readings on grey water when the valve is open and nothing is coming out; plus anything from 100% to warnings below 25% on fresh when I know that its at least 75% full!

My Bess was more accurate I think

Graham:smile2:


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## deefordog (Dec 31, 2013)

I know when our tank is full and needs emptying when the waste pipe backs up into the shower tray lol.


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## powerplus (Oct 6, 2014)

hi

got my van back today after having the winter pack fitted

this included new probes

when i collected the van i was shown the old probes the waste were quite corroded and covered in scale and slime

no wonder it gave a bad reading

with the new probes it does now give good readings

i checked it as i was filling the water tank and then run the tap and watched as the water tank fell and the waste tank filled

definatly worth keeping them klean


barry


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## Pat-H (Oct 30, 2009)

Yes our Swift has three prongs. The fresh water one isn't a problem but I do remove and clean it regularly.
The waste one is a real pain. Waste matter is always getting stuck to it so I get all sorts of readings.
I pretty much ignore it now. I know when it' getting full by how much we use it.
Worst case the waste tank has holes near the top so will just overflow and leak out.


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## Penquin (Oct 15, 2007)

powerplus said:


> definatly worth keeping them klean
> 
> barry


The problem to which there seems to be a variety of answers but none are definitive is HOW should they be cleaned?

Careful rubbing? Soaking in vinegar? Cleaning with Cola ?

I am sure there are many more ideas, but has anyone come across a really definitive answer that we should all use? Or should be just fit new probes every few years ?

Dave


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## Pat-H (Oct 30, 2009)

The probes just measure the resistance across them. when in the air the restistance is high when in liquid it gets lower.
When covered in fat and muck the resistance can be higher so the reading maybe wrong. If muck or waste food gets stuck across them the resistance will be lower so again a wrong reading.

You can clean them with just about anything. Doesn't really matter as long as they are clean. The waste tank also has to be cleaned or muck in there will soon contaminate them.

I take my probes out. Flush the tank. Clean the probes with a scourer and replace. Good then for a year or more.


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