I realise this thread is old, but in the hope of being helpful to someone else...
I've had this problem a couple of times, and it seems that the switch is susceptible to dirt/grease which will stop it latching as you've described. In some cases I can get away with cleaning it from the...
Hi,
I hope someone can help.
We get this problem about half of the time when the toilet finishes filling after a flush. Rather than the water cutting off nicely, it stops, then starts, then stops - at a beat of about twice a second. This goes on for a couple of seconds until it settles...