Thetford toilet

[IanB1485]

With IDC connectors you do not strip back the insulation , the insulation holds onto the metal 'tooth' within the connector The action of closing the lid normally pushes the wire onto the blade and completes the action , however with the ones you have bought, the cover closes on a hinge so the little plastic 'tabs' don't come down on the wire at right angles and aren't very strong . I prefer to press each wire onto the respective 'tooth' .Then once all four are fitted,close the cap to secure the connector onto the wires.See the attached photos . The first one shows a wire being placed onto the 'tooth' and the second one ,with the connector on a secure flat surface I have pressed the wire fully onto the tooth with a small piece of steel rod(its actually an old small screwdriver with the end ground flat). you can see the edges of the 'tooth' protruding either side of the wire.Closing the cap completes the process

 

[Martin_E]

BT used to do a similar fix for their cables, there used to be a forked tool to push the cables into the sharp prongs

 

[GRS1661]

I have a similar infuriating issue. Thetford C250.
Push button stopped working.
I have replaced PCB, didn’t work
Replaced reed switch pcb. Didn’t work.
Just replaced full pump & wiring loom. Doesn’t work!
Fuse is fine and there is 13.5v at the connector in the cassette hatch.
Any further ideas before I set the whole thing on fire !! 😡

 

[birdman101]

Back of cassette should be fuse often corroded. With cassette out at the right side of the door opening at the front floor corner is a small plastic panel. If you lever this out you usually find a connector there. Check if you have voltage there comming from the consumer unit.

 

[IanB1485]

Check the voltage at the flush pcb , both with the pump switch off and then pressed , if the voltage drops then the wiring from the cassette area is knackered and the loom needs replacing. ,attached is a schematic diagram of the wiring. there are slight variations in the pcb layout but it should help you determine where the voltage is being lost. Also don't assume its the +12V supply thats faulty , a faulty 0V will give similar results so if you can, run a wire from the battery negative and use that as your 0V reference for your multimeter to check voltages and if the 0V at the pcb rises to about 10-12V when you press the flush switch its the 0V ( black wire) which is faulty(high resistance).