Currently I am using the modem Quectel EC20CE 16 ports firmware EC20CEFBKR03A05M2G_GW in Vietnam,when I insert the sim card Mobifone into the modem and using the AT+COPS,the response show successfully +COPS:0,0,“Mobifone”,7, then i get the information of the sim card using AT+CUSD=1,“*101#”,15,the response is +CME ERROR:100,but when I use another Quectel EC20 16 ports modem using firmware EC20CEFAGR06A17M4G,everying works perfectly.
So my question is will it work fine if i update the current modem the new firmware.
this is the image of the modem need to update firmware:
Dear kieng_quan_hu_nh,
Thank you for reaching out.
We understand your module registers successfully on Mobifone with +COPS: ...,7 (LTE), but AT+CUSD returns +CME ERROR:100. USSD is a network-dependent feature and may fail when the module is camped on LTE (depending on operator support and firmware behavior).
Please first confirm the serving RAT using AT+QNWINFO, and confirm USSD support via AT+CUSD=?. If the module is fixed to LTE-only scan mode (e.g. NWSCANMODE=3), please change it to allow 2G/3G and then reset RF / reboot (e.g., AT+CFUN=0/1) before retrying USSD.
Regarding firmware upgrade, kindly provide the full firmware version, AT+QGMR?. I will provide you the most compatible latest firmware version for this module.
Thank you.
Best Regards,
Aghelan