My unit was working fine but finally the slowly flashing yellow light came back. I had already tried the usual improvements but didn’t help so I decided to replace the weight sensor. However, the problem still remained. Sometimes it just worked, and then it failed. I finally found the answer in this thread which gave the answer: it’s the lighting in the bonnet which is to blame as it also contains a sensor. As a quick fix you can disable the night light (press the on / off button for 5 seconds) or you’ll have to replace the entire bonnet. For now, the light has been turned off and the unit is working fine again.
After replacing the weight sensor I noticed that the pinch sensor metal bits were heavily corroded:
And via a small gap a lot of litter will get very close to it which will greatly accelerate the corrosion IMHO. As an experiment I used an acrylic sealant to close this gap. I’m very confident that this won’t stop the protection from working as it almost doesn’t stick to the plastic surface. So in my case I’m confident that the pinch protection still works fine but I can’t recommend you to do the same as it can be dangerous to the health of your cat(s). So please do some testing before you try this.
So there’s a sensor in the ligh module, cleaning it didn’t help
Mostly computer related stuff 