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Mastering GPS Logistics: The AutoGrade Protocol & Port 5120
The AutoGrade protocol, operating on Port 5120, is a high-performance communication standard optimized for enterprise-grade telematics. It provides a stable environment for real-time tracking, fuel monitoring, and remote engine immobilization.
1. Device Comparison
| Device Model | Standard Port | AutoGrade Support | Primary Use Case |
|---|---|---|---|
| Jimi VL512 | 5120 | Native | 4G LTE OBDII Fleet Management |
| SinoTrack ST-901L | 5120 | Configurable | Motorcycle/Vehicle Tracking |
| Meitrack T633L | 5120 | Advanced | Industrial Logistics & Sensors |
2. General 4-Pin Wiring Diagram
[ GPS TRACKER UNIT ]
|
+———+———+———+
| | | |
[RED] [BLK] [ORG] [YEL]
| | | |
VCC(+) GND(-) ACC RELAY
|
+———+———+———+
| | | |
[RED] [BLK] [ORG] [YEL]
| | | |
VCC(+) GND(-) ACC RELAY
3. Advanced Relay Connection (Engine Cut-Off)
To enable the “Remote Immobilization” feature via the AutoGrade protocol, follow this 5-pin relay schematic:
Important Safety Note: The relay should typically cut the Fuel Pump or Starter wire. Never cut the main ignition wire while the vehicle is in motion unless the protocol supports speed-limited immobilization.
[ RELAY 12V/40A ]
Pin 85: Connect to Yellow Wire (GPS Relay Output – Negative Trigger)
Pin 86: Connect to 12V Positive (Battery +)
Pin 30: Connect to one side of the Cutted Wire (Fuel Pump)
Pin 87a: Connect to the other side of the Cutted Wire (Fuel Pump)
Note: Pin 87 remains empty for “Normally Closed” (NC) setups.
Pin 85: Connect to Yellow Wire (GPS Relay Output – Negative Trigger)
Pin 86: Connect to 12V Positive (Battery +)
Pin 30: Connect to one side of the Cutted Wire (Fuel Pump)
Pin 87a: Connect to the other side of the Cutted Wire (Fuel Pump)
Note: Pin 87 remains empty for “Normally Closed” (NC) setups.
4. SMS Configuration Commands
Jimi / Concox Series
SERVER,1,yourserver.com,5120,0#
RELAY,1# (To Cut Engine)
RELAY,0# (To Restore Engine)
RELAY,1# (To Cut Engine)
RELAY,0# (To Restore Engine)
SinoTrack Series
8040000 yourserver.com 5120
9400000 (To Cut Engine)
9410000 (To Restore Engine)
9400000 (To Cut Engine)
9410000 (To Restore Engine)
5. Troubleshooting
- Port Check: Verify Port 5120 is open on your server (TCP/UDP).
- Relay Click: If the relay doesn’t “click” when sending the command, check if the GPS tracker is receiving enough power (VCC).
- Signal: Ensure the device has a valid GPS/GSM signal before sending cut-off commands.
