What is XCMG XE750D Fault Code E1107(3) SPN2630 FMI1?

Fault Code E1107(3) SPN2630 FMI1 indicates a data issue with the Engine Coolant Level sensor circuit, specifically showing that the sensor data exists but is above the normal operating range (FMI1 = Data Valid But Above Normal Operational Range).

This fault code is part of the J1939 diagnostic protocol used in modern diesel engines. SPN2630 directly references the Engine Coolant Level monitoring system, which is critical for preventing overheating and catastrophic engine damage on the XCMG XE750D excavator. The FMI1 designation means the Engine Control Module (ECM) is receiving a signal from the coolant level sensor, but the voltage reading is abnormally high, suggesting either an actual low coolant condition or a sensor/wiring malfunction. For a machine of this size operating in demanding conditions, accurate coolant monitoring is essential to protect the expensive diesel powerplant.

Common Symptoms

• Yellow or amber warning light illuminated on the instrument cluster, often with a coolant-related icon
• Audible alarm sounding intermittently or continuously during operation
• Engine derate mode activated, limiting power output to 75% or less to protect the engine
• Coolant temperature gauge may read normally despite the fault code being present
• Stored fault code in ECM memory even after coolant is topped off

Potential Causes

The most common technical causes for this specific fault on used XCMG excavators include:

• Low coolant level in the expansion tank or radiator due to leaks or normal consumption
• Faulty coolant level sensor with internal resistance drift (common after 5,000+ operating hours)
• Corroded or loose electrical connector at the coolant level sensor (check connector C142 on XE750D models)
• Damaged wiring harness between sensor and ECM, particularly at harness routing points near the engine block where vibration causes chafing
• Failed ECM coolant level input circuit (rare, but possible on machines with electrical system damage history)
• Aftermarket coolant with incorrect conductivity affecting sensor readings

How to Troubleshoot and Fix Code E1107(3) SPN2630 FMI1

Step 1: Visual Inspection and Coolant Check Begin by checking the actual coolant level in both the radiator and expansion tank with the engine cold. Top off with the manufacturer-specified coolant mixture if low. Inspect for visible leaks around hoses, radiator, and water pump. On used excavators, check for evidence of previous repairs or sealant use that might indicate recurring coolant loss.

Step 2: Inspect Sensor and Connector Locate the coolant level sensor (typically mounted on the coolant expansion tank). Disconnect the electrical connector and inspect for corrosion, bent pins, or moisture intrusion. Clean with electrical contact cleaner if needed. Check the connector locking mechanism—worn connectors are common on machines with 3,000+ hours.

Step 3: Test Sensor Resistance Using a digital multimeter, measure the resistance across the sensor terminals with the sensor removed from the tank. Compare readings against XCMG specifications (typically 50-150 ohms at room temperature for this sensor type). If readings are open circuit (OL) or above 500 ohms, replace the sensor.

Step 4: Check Wiring Harness Continuity With the sensor disconnected, test continuity between the sensor connector pins and the ECM connector (refer to XCMG wiring diagrams for pin locations). Check for shorts to ground or open circuits. Pay special attention to harness routing near the engine mounting points where vibration wear is common on used machines.

Step 5: Verify Repair and Clear Code After repairs, fill the system with coolant, run the engine to operating temperature, and use XCMG diagnostic software or a compatible J1939 scan tool to clear the fault code. Monitor for code recurrence over the next several operating hours.

---

Disclaimer: This guide provides general diagnostic information for experienced technicians. Always consult the official XCMG service manual for your specific machine serial number and software version. If you're uncomfortable performing electrical diagnostics, contact a certified XCMG dealer or qualified heavy equipment technician to avoid further damage to the ECM or engine.