UC200TEM Unknown signal quality

Hi Team,

I have got a new EVB for UC200TEM module. I’m trying basic functionalities. I am using Qnavigator to send commands. Here are my queries:
Connection: Micro USB on EVB to USB connected to PC, EVB COM1 (main) connected to PC via (RS232-USB cable).

  1. Power LED is on. Pressing PWR_KEY turns on status LED. So only 2 LEDs turns on. Remaining LEDs are off. I am expecting after using PWR_key, NET_mode and NET_status LEDs to be turned on.
  2. Basic AT commands are working. I am able to send SMS as well. However, AT+CSQ gives 99,99 (unknown quality). What could be the reason? Perhaps, the net_mode and net_status leds are not working, which may explain the reason.

Kamlesh Bharodiya

Dear Kamlesh,
Thanks for your inquiry in Quectel forum.
For your issue, it is better to check more information about module, such as the following commands:

Dear Kyson,

Thanks a lot for your prompt response.
I am sending the command responses.
[2020-09-24 12:51:38:487_S:] ati
[2020-09-24 12:51:38:562_R:] ati
[2020-09-24 12:51:38:562_R:] Quectel
[2020-09-24 12:51:38:562_R:] UC200TEM
[2020-09-24 12:51:38:562_R:] Revision: UC200TEMAAR02A01M16

[2020-09-24 12:51:38:562_R:] OK
[2020-09-24 12:51:45:919_S:] at+cops?
[2020-09-24 12:51:45:983_R:] at+cops?
[2020-09-24 12:51:45:983_R:] +COPS: 0,2,“40554”,3

[2020-09-24 12:51:45:983_R:] OK
[2020-09-24 12:51:52:263_S:] at+cpin?
[2020-09-24 12:51:52:332_R:] at+cpin?
[2020-09-24 12:51:52:332_R:] +CPIN: READY

[2020-09-24 12:51:52:332_R:] OK
[2020-09-24 12:51:58:735_S:] at+csq
[2020-09-24 12:51:58:795_R:] at+csq
[2020-09-24 12:51:58:795_R:] +CSQ: 99,99

[2020-09-24 12:51:58:795_R:] OK
[2020-09-24 12:52:09:695_S:] at+cgreg?
[2020-09-24 12:52:09:751_R:] at+cgreg?
[2020-09-24 12:52:09:751_R:] +CGREG: 0,1

[2020-09-24 12:52:09:751_R:] OK
[2020-09-24 12:52:28:919_S:] at+qeng=“servingcell”
[2020-09-24 12:52:28:976_R:] at+qeng=“servingcell”
[2020-09-24 12:52:28:976_R:] +QENG: “servingcell”,“NOCONN”,“GSM”,xx,xx,xx,xxx,xx,x,x,-52,xx,xx,xx,xx,xx,x,-,-,-,-,-,-,-,-,-,"-"

[2020-09-24 12:52:28:976_R:] OK

Also, I found this:

  1. Seems that the AT+CSQ command will not work here. Is it true?
  2. Why I am not seeing the net_mode and net_status leds on?
  3. Response of QENG command provides signal dbm. Should I go ahead with this and not expect at+csq’s response to be correct?
  4. My main task is to post and get http/https requests. But without net_mode and net_status on, how can I get/post requests?


You can try to upgrade the firmware to have a try. Please email to support@quectel.com to get the latest firmware and upgrade tool. Thanks!

Hi Kyson,
I got latest firmware and upgrade tool from support team. However, I am not able to upgrade it. The tool shows this: (I tried changing the baud rate to 115200 as well. same issue reported)

COM port is correct, because using QNavigator, I am able to send commands on this port. But using Qnavigator also, I saw this:

At the same time, device manager lists as below.


Please help.


Dear Kamlesh,’
It seems like that lack of the module USB driver, please ask support email to provide it. Thanks!

Hi @Kyson,

I installed the drivers and now the device driver looks like this:


  1. I see the error on QFlash, “Error tool cannot detect platform name”, Hence not able to update the firmware.
  2. Rest of the issues presist. [net_mode and net_status leds are off, at+csq not working, not able to get/post http requests]
    Also, the log from few at commands:

Please help.


Please do not unzip the firmware package, and choose the USB diag port. Then follow up the indication to reset the module and start upgrade the firmware. Thanks!

1 Like

Thank you @Kyson. The issue resolved, I am able to see now, net_mode led on. CSQ command is working. However, I am run into another issues. I will post that into different thread.

OK.Thanks for your updating. We can close this topic now. Thanks!