MangOH yellow cannot connect to

Our mangOH yellow cannot connect to via USB cable (but we can find others Sierra serial port on PC)
We are wondering whether the process OF ECM not working was caused by insufficient memory , is this guess reasonable?

The memory usage after we enable LTE , BT , Wi-Fi function:

Which one is responsible for handling the connection of emc0 (
How do we confirm that the process of ECM is operating normally?

you need to check dmesg in your PC and see what network interface is generated.
For example, if it generates usb0 interface for ECM communication, you need to set the IP address:

sudo ifconfig usb0

After that you should be able to ping

Thanks for your response
This problem is caused by disable “dnsmasq”