seems same issue as this one
@dl5162 , any idea how to solve this?
Yes, looks like exactly the same issue.
I don’t have any better idea than what’s discussed in the discussion you linked to. My last post there includes a link to a .nvu file which might fix the problem. Or make it worse. All warnings are still applicable.
i will try to flash this .nvu and give you the result i get. but anyway i have ordered the new module and stick with verified vid:pid.
well, i have flash your .nvu with lastest generic .cwe. still cannot fix this problem. so i have brick this module. good bye 8$ 
oh god, i did fix this by many many wierd steps on both Windows10 and Ubuntu 20.04, thanks you @dl5162 , this .nvu is helpful to change the pid, so driver and usb bus can be detected, my works are:
- using physical pc, dont use virtual machine with usb passthrough because the vm host will not detect usb bus without driver
- Clean the hardware, m2 pin, m2 adapter pin to avoid pin missing or short
- must know the device usb setting, i remember it was 3 so i plug it on usb 3.0 port
- Plug in on windows 10, install the driver with flag DisableUsbCompAutoUpdate=0, it help release the wrong usb bus of device so it can be register
- flash our .nvu with generic cwe firmware, it help change my vid:pid from 1199:68b1 to 1199:9071, i am using the fdt tool downloaded on the sierra device page with flag -d g5k -fd “firmware folder path” -f generic firmware.cwe bjorn.nvu -log. It run without any issue, device flash and restarted
- Well, now it have accepted vid:pid, boot up an Ubuntu machine, using swi_script or the qmicli command to set device work mode to 6 or 8, i was set it as 6
- Now booting it back to windows, unistall driver, reinstalling it with flag DisableUsbCompAutoUpdate=1 GPS=1 GPSAUTO=1 USBCOMP=6 WIN8BUSDriver=1, after done, it will detected the com port inside device manager, well
- I am not likely use connect the com with Huawei Modem driver in Windows, i think i will be safer to connect it with minicom or putty in ubuntu so i boot it back onto ubuntu and ttyUSB registered as well
thats my adventure with my em7430
Thanks for sharing that procedure. It helps a lot in case anyone else hits this issue.
And great to hear that you were able to rescue your modem. I do find it amazing that this config, made by a tool I hacked together based on reverse engineering .cwe and .nvu files, is able to fix a problem like this. I have never seen any docs describing the file format or the firmware mechanism it uses, so there are obviously large holes in my understanding. But good enough is good enough 
yeah, hope it help anyone-else who need. em74xx are very widely used
Hello, I also have a 4g module of dw5816e. I want to flash it to the latest universal firmware. I have been researching it for many days and have not been successful. Can you list more detailed flashing steps?
Are you testing in Linux or Windows?
For windows, what do you see in device manager?
For linux, did you install the USB driver?
I forgot to mention one thing. A dw5816e that is successfully refreshed using this method will display 413c:81cb when refreshed under Linux. However, a dw5816e that fails to be refreshed using this method will not display 413c:81cb when refreshed under Linux.
is the linux platform able to enumerate the /dev/ttyUSBx port?
Are you able to update the firmware via Airvantage platform over the air?
May I ask how you updated the firmware of dw5816e? Is it on Windows or Linux? How to install the driver? Are there any specific steps?
There should be windows driver from dell
See if this helps
You have sent these messages before, and I have reviewed them without solving the problem. I think I should use a Dell computer to install the drivers and change the Vid
so you cannot enumerate the AT command port in linux?
I’m not very good at using Linux yet, I’m learning. I’m not sure if this article is useful, but I’m currently studying. Sierra Wireless EM7455: How to enable COM ports | zukota.com