Banana pi R3 Mini Crashing

New to this linux/ openwrt world. Need some help from smarter people than me. I have a Banana Pi r3 mini.

Router crashes shortly after openwrt text logo, but only happens if my quactel rm520n-gl has a sim installed. If i remove the sim, router operates normally. How do i view crash logs?

Things I’ve tried, Wipe emmc and reinstall os. - do i need to go deeper the kernel level?

Reflash rm520n-gl, i did modify the ttl settings using adb but reflashed it back to stock as it was boot looping my router. Didn’t make a change.

Dont know where to go from here. :confused:

You should see a trace before reboot happens in debug uart. This may help here…

You know what, i was powering the r3 mini with my pc using a type c cable, I was using the same cable for serial access. I followed you suggestion and started using the UART and a dedicated power supply. No issues! Must have been my pc not powering the R3 properly. Many thanks!

Thanks for reporting back,yes powering r3mini via usb may not be enough. I also use dedicated power supply.