Which toilet is it?
The red light sounds like a stuck float. Take the cassette out, open it up and check it's not being fouled and is free to move.
The flush could well be the circuit board or it could be simply a blown fuse. Fuse would be my 1st port of call.
Do you mean it continues flushing until empty. If so could you hear the pump running. If the pump does not run but the tanks empties on its own it is the vacuum valve needs replacing. This stops it siphoning out. The Red light is the cassette full light. This usually stays on if the cassette is empty but the float inside is stuck up, usually with paper under it,
------------- 2023 Swift Archway Woodford, MK3 Kuga ST Line X 190 ps AWD Auto
Now 52 years Caravanning completed.
I suspect that when you cleaned the PC board you have may broken a "track" that was corroded? Easy to do, but you need a multi meter to check all tracks for continuity. Alternative is to buy a trfurbished PC board..
Quote: Originally posted by iank01 on 10/3/2024
I suspect that when you cleaned the PC board you have may broken a "track" that was corroded? Easy to do, but you need a multi meter to check all tracks for continuity. Alternative is to buy a trfurbished PC board..
No action required regarding the PC board as the OP confirmed in their last post that it was the fuse.