In the modern world of navigation technologies and telematics, vehicle owners are often faced with the need to identify installed equipment. IMEI of GLONASS device is not just a set of numbers, but a unique digital passport that allows the system to accurately identify a specific communication module among millions of others. Understanding the nature of this code is critical for correctly setting up a monitoring server, activating a SIM card, or verifying the legality of a purchased tracker.
Many people confuse this identifier with the internal ID of the device itself or the serial number of the case, which leads to errors when entering data into operators’ personal accounts. International Mobile Equipment Identifier is assigned to the GSM module built into the tracker, and it is through it that registration in cellular networks occurs for transmitting coordinates. Without correct reading of this code, full integration of the device into satellite monitoring systems is impossible.
In this article, we will look in detail at how IMEI differs from other markings, where to look for it on a physical device, and how to use special commands to obtain it remotely. You'll learn why this setting is key to your vehicle's safety and how to avoid common mistakes when working with telematics equipment.
What is IMEI and how does it work in GLONASS trackers
IMEI (International Mobile Equipment Identity) is a 15-digit unique code that is assigned to each device that can operate on GSM, LTE or 3G cellular networks. In the context of navigation systems GLONASS/GPS this code does not belong to the satellite positioning antenna itself, but to the GSM modem, which transmits the collected coordinates to the operator’s server. This is why a tracker that does not have a SIM card or GSM antenna cannot have an IMEI in the classical sense.
The structure of the code is strictly regulated by international standards and is divided into several semantic blocks. The first 8 digits are TAC (Type Allocation Code), which indicates the device model and manufacturer. The next 6 digits are the serial number of the specific unit produced at the factory. The last, 15th digit is a control digit and is calculated using the Luhn algorithm to check the integrity of the entire code when transmitting data.
⚠️ Attention: Never share the full IMEI code of your tracker with third parties in open sources. Knowing this code, attackers could theoretically clone the ID to another device or try to block your equipment through your telecom operator by impersonating the owner.
It is important to understand the difference between IMEI and internal Device ID. If IMEI is the passport of the communication module, then the device ID is the internal logical number that is written in the firmware to work with specific monitoring software. In 90% of cases of Chinese-made trackers (for example, Teltonika, Concox, Jimi), these codes may coincide or have a direct relationship, but in professional Russian systems they often differ. An error in choosing a code when registering with the server will result in the server simply not seeing incoming data packets.
Physical location of the code and how to read it
The search for an identifier begins with a visual inspection of the equipment itself. Manufacturers who care about the convenience of installers usually put markings on the device body. However, the location may vary depending on the tracker form factor. In compact models designed for flush installation, the label can be extremely small or located on the back of the board, which requires partial disassembly of the case.
The standard label contains not only the required 15-digit number, but also other important information: IMEI is often duplicated in the form of a barcode or QR code for quick scanning. There may be fields nearby SN (Serial Number) and MAC (for Wi-Fi or Bluetooth enabled devices). When reading, be careful: sometimes the sticker contains the prefix “IMEI:” or “SN:”, which does not need to be entered in the registration field, only numbers are required.
- 🔍 Body sticker: The most obvious option is located on the back cover or side of the device.
- 📦 Packing box: If the device is new and has not yet been installed, the code is always duplicated on the factory box next to the barcode.
- 📄 Product data sheet: In the warranty card or technical passport, the manufacturer is required to indicate the unique identifier of a specific instance.
If visual access to the device is difficult (for example, it is already installed under the car dashboard), you can try using software methods. Many trackers support sending SMS commands to obtain system information. For example, for some Concox models the command may look like a status request. However, this method only works if the device is already activated, has balance, and is properly configured to accept commands.
☑️ Check before purchasing a used tracker
Software methods for obtaining IMEI via SMS and commands
When physical access to the tracker is limited, remote control tools come to the rescue. Most modern models support text messaging with the number of the SIM card installed in the device. This allows you not only to find out the identifier, but also to check the operation status, balance and signal quality. To use this method, you need to know the phone number that is assigned to the tracker SIM card.
The command syntax depends on the manufacturer and model of the device. There is no universal command, but there are common patterns. For example, for many devices based on the platform Wialon or popular Chinese brands, teams like imei1? or get imei. After sending an SMS to the tracker number, it should send a response message with the requested information.
Examples of commands for popular brands:- Concox/GTK: Send SMS "imei1?"
- Teltonika: Via SMS command "getinfo" (requires permission settings)
- SinoTrack: Send SMS "111" (standard password) then request status
Please note that for SMS commands to work, the SIM card must support text messaging, and not just Internet traffic. In some tariff plans for IoT devices, SMS functionality may be disabled by the operator. In this case, the only software option is to log into the device’s web interface, if it is open, or use specialized configuration software via a USB cable.
What to do if the tracker does not respond to SMS?
If the device ignores your messages, check the following points: 1. Is there a battery charge or power supply. 2. Does the SIM card accept calls and does it have a positive balance? 3. Is there a PIN code set on the SIM card (the tracker cannot send a response until it unlocks the card). 4. Is the device within network coverage (check the GSM indicator).>
Differences table: IMEI, Device ID and Serial number
One of the most common problems when setting up monitoring systems is confusion in terms. Users enter the serial number of the case instead of the IMEI, or vice versa, after which the system displays a “Device not found” error. To avoid this, you need to clearly understand the difference between the main identifiers.
The table below provides a comparison of the main marking codes that you may encounter when working with GLONASS equipment:
Numbers or HEX| Parameter | Purpose | Format | Where is it used? |
|---|---|---|---|
| IMEI | Identification of the GSM module in the operator’s network | 15 digits | SIM card registration, operator blocking |
| Device ID | Logical number for the monitoring server | Personal account Wialon, Autotrack, etc. | |
| Serial Number | Serial number of case/board | Alphanumeric | Warranty service, warehouse accounting |
| ICCID | ID of the SIM card itself | 19-20 digits | Activating a tariff with a telecom operator |
As can be seen from the table, IMEI strictly tied to the modem hardware. If you replace the GSM module inside the tracker (which is technically difficult, but possible with repairs), the IMEI will change. At the same time Device ID You can often reprogram it through special utilities to “link” the device to another server or change its logical name in the system.
Checking device authenticity and status by IMEI
When purchasing used equipment or ordering a batch of trackers for a fleet, there is a risk of acquiring a counterfeit or stolen device. Checking by IMEI allows you to weed out illiquid goods. Official GSMA databases allow you to check whether a module is on the blacklist of lost or stolen phones, as trackers often use the same modules as mobile phones.
In addition, the check helps to identify “gray” devices in which the changed IMEI is programmed. Such trackers may work unstably in operator networks, since their identifiers may be duplicated with other devices, which causes registration conflicts on the network. Your carrier may block such devices automatically.
- 🛡️ GSMA Base: The official resource to check device lock status worldwide.
- 🌐 Manufacturer's website: Many brands (for example, Teltonika, Navtelecom) have their own verification services by serial number and IMEI.
- 📱 Android Applications: There are utilities that can read the IMEI of a connected modem via Bluetooth or USB.
If you find that the IMEI of your device matches the code of another gadget you know, or it consists of only zeros