TECHNICAL

Caravan & motorhome technical questions

Question

hi, i have a thetford 200CWE in my Abbey540 expression 2008, 1st changed the switch just 3 days ago due to it not working at all. that sorted a few mins later the flush stopped!! the old pump was removed and a new pump fitted but when the switch is activated there is nothing only the click of the switch. the pump does not run. there is no current to the wiring to the pump and to the switch, the fuse is good, and the battery shows that it is ok and charging well. the pump has been tested on a 12v battery and it whizzed round, could you throw any light on this pls. It seems to make no sense as all, was ok. then as soon as the wiring was cut to attach new pump it wont work. So I have new switch new pump all installed ans shrunk wrapped but still no current to switch or pump all fuses are good but no current to the switch the 12 volt cable seems to exit the unit and go behind the rear toilet wall so no help there, the book diagram states purple wire the colour into the pump is brown & blue in a black rubber casing have had van since ne and all has worked ok till I had service done and a new batt charger fitted and new water heater element, could the person fitting these have dislodge moved anything. just seems strange all new parts but no current HELP PLEASE! could take it back to service centre but it a bit far so thought I would try you first! No pressure then!! cheers, Dread.

Answer

There should be a terminal block in the cassette compartment where the supply wires enter the toilet. Have you checked that you have 12 volts here. If no 12 volts then you will need to trace the wire back to the fuse box and check that there is no break in the wire.
If you do have 12 volts at this point then you may have a faulty switch and you can check this by lifting the switch out and using a bit of wire to by-pass it, to make the pump operate.