2d42 does not turn on with batteries, for USB yes

cmjelectronica · Post time 2020-8-14 09:56:21

2d42 arrived with the batteries turned upside down, with the polarity reversed. It does not turn on with batteries, it only turns on with USB cable. It was tested with other batteries and it does not turn on. How can I repair it or how can I get the electrical diagram of the equipment to analyze the board

cmjelectronica · Post time 2020-8-16 00:31:59

Batteries are fine, 3.8v

cmjelectronica · Post time 2020-8-19 15:24:20

VUSB: 4.8v - VBAT: 3.7V - 3.3V : 3.1V