However, on modern LTE modules (EC25, EG95), this command is locked or gives an error: ERROR .

A fleet of trackers uses IMEI-based whitelisting. If one module fails, replacing it with a new Quectel module (with a different IMEI) would require re-whitelisting hundreds of devices. Changing the new module’s IMEI to the old one is a pragmatic solution.

Moreover, defines the IMEI as permanent and unchangeable. Future 5G modules may enforce this hardware-level permanence cryptographically, making all current modification methods obsolete.

Quectel officially advises against modifying the IMEI, stating that it can prevent the module from registering on networks. However, in certain versions of firmware (particularly older or unbranded, open-source firmware), specific AT commands may work. 1. Preparation To communicate with the module, you will need: A serial terminal application (like PuTTY or minicom). Drivers installed for the Quectel USB serial port. The module connected to a PC (USB or UART). 2. Identifying the Correct Port