Problem with Quectel EM12G

Hi. Modem periodically won`t work after reboot on Linux. Tested on Archlinux with kernel 5.17.1 and 5.19.8 with firmware EM12GPAR01A18M4G and EM12GPAR01A21M4G_01.007.01.007.

usb 3-1: new low-speed USB device number 5 using xhci_hcd
usb 3-1: device not accepting address

At this time EM06-E worked fine on same machine without problems.

First of all, you need to make sure that the EM12G is powered on when it is abnormal after restart, and check whether the terminal can identify the USB port of the module ls /dev/ttyUSB*. The module can only work normally if the module is identified by the USB port of the module when it is powered on. Via AT+CEREG? Check whether the second parameter returned is 1 or 5, if it is, the network injection is successful; otherwise, the module network injection identification needs to check whether the SIM card is not recognized or there is no traffic. If the module starts up normally under the previous three conditions, the SIM card can be recognized and the network injection is successful, it indicates that the module is normal, and it needs to check the device environment factors, I hope it will be helpful to you.