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how can i fix my cassette toilet in my swift challenger caravan?

hi have recently purchased swift challenger 1991 model and cant get the toilet to flush.we have replaced fuses and tried everything can you help?It is a thetford bench style cassette loo.
karen bishop

karen bishop
March 2007
when i bought my caravan it had water in an id pipe next to the cassette collection box, but as i used the caravan it went down & eventually the toilet ran out of water. this may sound stupid, but, how do you refill the toilet flush tank? if there is one. its a swift challanger 460/4 about 1991 year. thanks... ray

April 2013
thanks nigel and bob :) toilet didnt work took tryed fuse but was ok so took out motor under toilet roll holder was held in with philips screw though, not like yours nigel,anyway turned motor a few times with small screwdriver tryed it again and away we go thanks again
took me ten minutes once i looked here for answer,thanks emmet

emmett nixon
April 2011
Thanks guys. Just on hols first time this year - had van serviced 2 months ago - and no flush!! Read your article and as soon as I lifted the toilet roll holder, the pump sprang back into life - THANK YOU!!

Noticed a lot of black gunk in the water tank though, what's best to use to get rid of that?

Harvey - Bailey Pageant Auvergne 1998

June 2010
hi there i have just had the same problem its the pump its under the toilet roll holder cost me 30 pounds

July 2008
hi karen i had the same trouble if you look in where cassette toilet is outside take cassette out look in and you will find a switch right behind it there is a seperate fuse i hope this helps you ronnie

ronnie thompson
June 2008
Full pictorial instructions from Thetford for this procedure can be found by accessing

Then click on Wiring Harness

July 2007
I had the same problem on my 1994 Swift Challenger 490 SE. After reading Bob's (thanks Bob) post I decided to have a go myself. Just a couple of things to add really.
As well as fuse No 6 (10 amp) on the main fuse panel I discovered a fuse (in line) located near the pump switch. Couldn't find any reference to this fuse in the handbook, guess we're just supposed to know it's there. It's located in the cassette compartment near the connectors to the pump switches. It's a black knob which just unscrews. My fuse had blown, 2.5A which I replaced with a 3.15A but unfortunately this didn't fix the problem. There are actually two micro switches that both have to be activated for the pump to work. One switch is activated (closed) when the cassette is installed, prevents the pump from working unless the cassette is in place, for obvious reasons. The second switch is used to activate the pump when pressing the flush. Either of these could be faulty. Getting at these switches isn't to bad once you know how. First thing to do is remove the flush button by removing the stopper from the top (prises off) and using a long philips screwdriver undo the screw in the centre. Now need to remove the housing containing the switches, do this by removing the four screws holding the housing in place, there is one screw at the back on the right that is a little unsighted and fiddly. Now remove by unplugging the two connectors. I then used a volt meter to check the two switches, fuse holder and complete circuit in this housing. I appeared to have a problem with the fuse holder but that disappeared after a bit of messing about. Checked I had power at the connectors which I did. Assembly is obviously just the reverse. That just left the pump itself, located under the toilet roll holder which just prises out. Removed the pump by cutting the wires as Bob suggested. Tested pump on battery but didn't work, gently knocked it as suggested still no joy, then used a screwdriver to rotate the propellers of the pump through the access hole in the base of the pump. B**ger me, it started working, (try this before cutting the wires and you won't need to do the next bit). Reconnected pump using terminal block and insulating tape, tested in situ and Bob's your uncle (actually I don't think he is).

Sorted!!!! Cost me nothing other than 3 hours of my time.

Nigel Franks
April 2007
I've got the same problem. Check first you have turned on all main switches at the panel [I forgot one and couldn't understand why the heating fan didn't work]
IF you know what wires are going to the cassette then test them at fuse point for current as the main panel pump switch could be faulty. On my panel over the stove is a pump switch and this is the master switch for the freshwater and cassette pump circuit and glows red to show its on. Remember one thing never run a pump dry. its ok when water levels drop to zero as the pump is still wet and speeds up.

if all is on then : You can visually test current is getting to the pump, but best at night. Turn all 12 volt power switches on at the panel and one of the 12volt lights. Press the flush knob and take note if the light slightly dims. If the light is not effected it may be the flush switch which is I'm told a bugger to get to. This involves removing the waste tank and on the left I think is the switch unit about 6" in and from what I can see has to be worked on by mirror the wires are push fit. I am trying to get hold of Thetford to get a diagram and instructions on removing the switch [bad designe] if lgith is effected then power is reaching the pump and the pump has seized. To access the pump remove the toilet roll holder and its casing then you will see the pump in the water tank. Lift the pump out of the water from it's seating and give it a tap with a pin hammer, not too hard and not too soft hold it in the water and press the flush again if the light still dims and the pump still doesn't work then it means a new pump. £15 for a pattern one and £28 for a proper type but I bought a £15 one and can't see the difference. Now for the replacement bit not easy as the switch unit is a bugger to get at so on advice I've been told the best way is cut the existing pump free and wire the new into the existing wires using a small electrical terminal block then wrap the block in waterproof tape, wrap it well past the block. If that was the cause you now have a toilet that flushes. If you want an exploded picture of the Thetford cassette toilet to give it it's proper name send me email and I'll take a digi picture of it and transfer to my computer then on to you by email which might explain better the layout of the cassette system.


March 2007


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