Introduction
Thank you for choosing the SinoTrack ST-902L 4G Mini OBD II GPS Tracker. This device is designed for real-time vehicle tracking, offering anti-theft features and location monitoring through a simple plug-and-play installation into your car's OBD-II port. It operates on 4G LTE-FDD and GSM networks, providing reliable tracking and various alarm functions.

This manual provides detailed instructions on how to set up, operate, and troubleshoot your GPS tracker to ensure optimal performance.
Safety Information
- Ensure the device is installed securely and does not obstruct driving controls or visibility.
- Do not attempt to disassemble or modify the device, as this will void the warranty and may cause damage.
- Keep the device away from extreme temperatures, direct sunlight, and moisture.
- Use only compatible SIM cards as specified in the setup instructions.
- The OBD-II interface is used solely for power and data communication; this device does not provide car diagnostic functions.
Package Contents
Please check the package for the following items:
- SinoTrack ST-902L 4G Mini OBD II GPS Tracker
- User Manual (this document)

Specifications
| Feature | Description |
|---|---|
| Model Name | ST-902L |
| Network | 4G LTE-FDD B1/B2/B3/B4/B5/B7/B8/B28/B66, GSM/850/900/1900/2100Mhz |
| Interface | Standard 16-pin OBD-II |
| Battery | Built-in 120mAh / 3.7V |
| Functions | Real-time tracking, History Route playback, Leaving Alarm, Speeding Alarm, Shocking Alarm, Low battery Alarm, GPRS & SMS mode support, Map location inquiry |
| Installation | Plug-and-play, no wiring harness required |
| Item Weight | 0.12KG/PC |
| Item Dimensions (L x W) | 4cm x 3.5cm |

Setup Guide
1. SIM Card Preparation and Installation
The SinoTrack ST-902L requires a Micro SIM card (without PIN code) for network connectivity. The device does not include a SIM card; you will need to purchase one separately from your local provider.
- Choose a GSM SIM card: Ensure it is a Micro SIM card and does not have a PIN code enabled.
- Open the SIM card slot: Slide the cover up to open the device.
- Insert the SIM card: Push the card slot horizontally to the right, then insert the SIM card. You should hear a clicking sound when it's properly seated.


2. Device Installation
The ST-902L is a plug-and-play device. Simply connect it to your vehicle's 16-pin OBD-II port.
- Locate the OBD-II port: The OBD-II connector is typically found in one of six common locations in a car, most often under the dashboard on the driver's side.
- Plug in the tracker: Insert the GPS tracker into the OBD-II port.
- Verify power: After plugging in, the orange and blue lights on the device should light up, indicating it is powered on.
- Initial GPS signal acquisition: Place the device in an open area for approximately 30 seconds to allow it to acquire a GPS signal. The LED lights will remain lit once the device is working normally.


3. Initial Configuration (SMS Commands)
Before online tracking, you need to configure the APN (Access Point Name) and server IP/Port via SMS commands. Replace 0000 with your device's password (default is 123456, change it after receiving the device).
- Set APN: Send SMS to the tracker's SIM card number.
- If APN does not require username/password:
8030000 APN(e.g.,8030000 CMNET) - If APN requires username/password:
8030000 APN APNuser APNpassword(e.g.,8030000 CMNET CMNET CMNET)
Note: The APN is specific to your SIM card provider. If you don't know it, contact your provider or check online resources like apn.how.
- If APN does not require username/password:
- Set IP and Port: Send SMS:
8040000 45.112.204.246 8090(This sets the server to Pro.SinoTrack). - Set Working Mode to GPRS: Send SMS:
7100000(This enables online tracking. Default is SMS mode).
The tracker will reply with "SET OK" for successful commands. To verify settings, send RCONF to the device.
Operating Instructions
1. LED Status Indicators
| LED Color | Status | Meaning |
|---|---|---|
| Blue (GPS) | Flashing | No GPS Signal or GPS starting |
| Blue (GPS) | ON | GPS OK (signal acquired) |
| Orange (GSM) | Flashing | No SIM card or GSM starting |
| Orange (GSM) | ON | GSM OK (network connected) |
2. Tracking via SMS Commands
You can control the tracker and get location information by sending SMS commands to the SIM card number in the device. Replace password with your device's password (default: 123456).
- Get Location with Google Link: Send
669+password(e.g.,669123456). The tracker will reply with a Google Maps link to its current location. - Get Location by Phone Call: Call the SIM card number in the tracker. It will hang up and reply with a tracking message containing a Google Maps link. If the device is in an invalid location, it will send the last valid location and then update when a new location is acquired.
- Set Control Number: To receive alarms and reports, set up to three control numbers. Send
Number+password+blank+serial(e.g.,+8613950443465123456 1for the first number). - Change Password: Send
777+NewPassword+OldPassword(e.g.,777newpass123456). - Change Time Zone: Send
896+password+E/W+HH(e.g.,896123456E00for East 0 time zone). - Send Location Daily: To receive daily location reports, send
665+password+HHMM(e.g.,6651234561200for 12:00 daily). To close, send665+password+OFF. - Geo Fence Alarm:
- Open:
211+password - Close:
210+password - Set Geo Fence (in meters):
005+password+meters(e.g.,0051234561000for 1000 meters).
- Open:
- Over Speed Alarm: Send
122+password+blank+XXX(e.g.,122123456 120for 120 KM/H). Set XXX to 0 to close. - Mileage:
- Set initial mileage:
142+password+M+X(e.g.,142123456M1000for 1000 meters). - Read current mileage:
143+password.
- Set initial mileage:
- Shock Alarm:
- Open:
181+password+T(T is shocking time in seconds, 0-120s). - Close:
180+password.
- Open:
- Low Battery Alarm: The tracker automatically sends an SMS to the first control number when the battery is low.
- Call Mode:
- Call mode ON (alarms call and send SMS):
150+password. - Call mode OFF (alarms only send SMS):
151+password.
- Call mode ON (alarms call and send SMS):
- Sleep Mode:
- Open Sleep mode (tracker sleeps when vehicle stops for T minutes):
SLEEP+password+T(e.g.,SLEEP1234565for 5 minutes). - Close Sleep mode (tracker works all the time):
SLEEP+password+0.
- Open Sleep mode (tracker sleeps when vehicle stops for T minutes):
- Set Time Interval (GPRS upload): Send
805+password+blank+T(T is interval in seconds, 10-18000s). Set T=0 to close GPRS.
3. Tracking via Web Platform
For real-time online tracking and history playback, use the SinoTrack web platform.
- Website: www.sinotrack.com or 45.112.204.246
- Server: Pro.SinoTrack
- User Name: Your device's ID number (found on the tracker).
- Password: 123456 (default, change after receiving device).

4. Tracking via Mobile Application
Download the official SinoTrack PRO app for iOS or Android for convenient mobile tracking.
- App Name: SinoTrack PRO
- Download: Search "SinoTrack PRO" on App Store (iOS) or Google Play (Android), or scan the QR code provided.
- Login:
- Server: Pro.SinoTrack
- User Name: Your device's ID number.
- Password: 123456 (default).



Maintenance
- Keep Clean: Regularly wipe the device with a dry, soft cloth to remove dust and debris.
- SIM Card Balance: Ensure the SIM card has sufficient balance and an active data plan for continuous tracking.
- Firmware Updates: Check the SinoTrack website or app for any available firmware updates to ensure optimal performance and new features.
- Avoid Harsh Conditions: Do not expose the device to extreme temperatures, water, or corrosive substances.
Troubleshooting
If you encounter issues with your SinoTrack ST-902L, refer to the table below for common problems and solutions. For further assistance, please contact customer support.

| Question | Answer |
|---|---|
| Cannot login app or website? | Please choose the correct SinoTracker Server (Pro.SinoTrack) on app/website (www.sinotrack.com). Ensure correct IP/Port: 45.112.204.246:8090. |
| Device shows "unactivated" on platform? | Make sure you set the correct IP/Port and APN. If APN is "internet", contact SIM card provider for correct APN. |
| Device shows "offline" on platform? | Please send SMS command: RCONF to device to check GPS Setting, IP, PORT, APN. Try sending RESTART. Check SIM card balance and internet plan. |
| Device shows China location on platform? | Test location before sending device or ensure valid GPS signal. |
| Device icon is Yellow color? | Put device in an open area to get good GPS signal. |
| Device shows incorrect location? | Please insert SIM card correctly. Check the SIM card with credit. |
| Device doesn't respond to SMS command? | Please check if the SIM card supports GSM or 3G network. If there's a PIN code, cancel it. Try another operator SIM card. |
| What's the APN? | APN is Access Point Network of your SIM Card. Check with your SIM card provider or refer to apn.how. |
| How can I set APN? | Send SMS command: 803+Password+Blank+APN. Example: 8030000 internet. If APN needs user/pass: 803+Password+Blank+APN+Blank+APNuser+Blank+APNpass. |
| How can I set IP and Port? | Send SMS command: 804+Password+Blank+IP+Blank+Port. Example: 8040000 45.112.204.246 8090. |
| How can I get account for login platform? | Website: www.sinotrack.com. User ID: ID number on device. Password: 123456 (change it when you get product). |
| How can I get Group user for Multiple devices? | Contact SinoTrack support with all ID numbers of trackers you want in a group, and tell them your desired user name. |
Additional Functions:
- RESTART: Send
RESTARTto the device to reboot it. - RCONF: Send
RCONFto the device to read its current configuration settings. The device will reply with a detailed SMS including software version, ID, password, control numbers, working mode, alarm settings, APN, IP/Port, GPRS upload time, and time zone.
User Tips
- SIM Card Choice: Choose a SIM card with a reliable 4G data plan from a local provider for the best tracking performance. Ensure it supports GSM/GPRS.
- Password Security: Always change the default password (123456) immediately after receiving your device to enhance security.
- Group Management: If you manage multiple vehicles, take advantage of the free group account feature by contacting SinoTrack support to monitor all devices from a single account.
- Outdoor Testing: When testing the device for the first time or after a long period of inactivity, ensure it is in an open outdoor area to facilitate quick GPS signal acquisition.
- APN Accuracy: The most common issue for devices not coming online is an incorrect APN setting. Double-check your SIM card provider's APN details carefully.
Warranty and Support
For any questions, technical support, or warranty inquiries, please contact SinoTrack customer service. You can reach them via email at sino@sinotrack.com. When contacting support, please provide your device's ID number and a detailed description of the issue for faster resolution.
SinoTrack offers a lifetime free tracking platform for all its devices, ensuring continuous access to your vehicle's location data without additional subscription fees.





