Dettol no touch soap dispenser ~ ques ~

[Micus]

Hello everyone,
Dettol stopped working. I opened it. And at the top of the neck, there is a phototransistor. The wires were completely rotten. Does anyone know what type of phototransistor it is, any markings so I can buy one?
Thank you very much

 

[Delta Prime]

Photo transistor, photo diode can you take a photo?
I opened my soap dispenser
I thought I would find a tiny little motor running the pump.
I was wrong!