Today, after less than a month of use, the Pico4 left controller stopped working. It refuses to power up, even when I use batteries that work in the right controller. The menu or any other button did not cause any reaction. The blue led did not blink at any moment like with the Picoright controller.
I checked the contacts of the battery case and found a lack of battery voltage. After disassembling 4x T2 screws (the only screws in the controller), I found that sweat got into the battery box and touched both case contacts. That resulted in melting weak point of battery contacts (where contacts were bent) and brake of connection.
The worst thing is that issue is easily preventable. If constructors only added a small layer of electric type, they could prevent short circuits caused by sweat. I have added a small electric-type patch over the working controller to prevent the same issue in the future.
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