Check by turning on a 12volt light in toilet cubicle or near where you can see it. Press the flush button if the light dims current is getting to the pump. If it doesn't the fuse may have come out which is accessable after removing the cassett think its on the left. If that's ok then it could be the switch but never had probs so don't know how to access it but have emailed Thetford to find out will post when I do.
Repair/replace.
If the light does dim the pump [co-incidental] impeller has ceased. Take out the toilet roll holder and pull the housing it sat in up [it's push fit no screws or clips] you will see the pump flush tube and the pump is held down by cage and one screw undo and remove pump, up end the pump and with small screwdriver turn the impeller gently until it runs free. Replace it back in the water and test before re-assemble. Whatever you do if you have to replace the pump cut the old one OFF don't try pulling the cable out and feeding the new one in to the switch you'll never do it without dismantling the toilet. Cut and splice is my advice join with small elec terminal block or scotch clips from car shop. Wrap with waterproof tape. Stow joint on inside shelf/ moulding at back of water tank.
You will find one of the wires has a thin tracer usually white on both pump wires put these together no matter what the tracer colour is don't put a plain single colour with a tracer colour it will probably send your pump in reverse and knacker it, or suck instead of pump out and the bowl might get sucked up the flush tube. [weak joke]
Nobby
October 2008
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