I need some help with SIM868 GSM/GPRS/GNSS Module for Raspberry Pi Pico. A few months ago I bought SIM868 module and RPI Pico, and it works just fine together.
But recently I bought another pair of RPI Pico and SIM868, and now when I connect them together using a female header, Pico just shuts down and disappears from Windows Device Manager. When I unplug Pico from SIM868, it turns on, the led starts blinking and it is visible again on Windows Devices. Standalone Pico works great with Micropython.
The question is What am I doing wrong? Maybe somebody has dealt with a problem like that.
P.S. I can do some voltage measurements and/or oscilloscope screenshots if it helps.