What is XCMG General Fault Code E1044?

Fault Code E1044 indicates a malfunction in the hydraulic pump control system, specifically an abnormal signal from the main pump solenoid proportional valve or its associated circuit. This diagnostic trouble code (DTC) is triggered when the Electronic Control Module (ECM) detects a voltage or current reading outside the manufacturer's specified range for the pump control solenoid.

In XCMG excavators, the proportional valve regulates hydraulic pump displacement based on operator demand and load conditions. When E1044 appears, the ECM cannot properly modulate hydraulic flow, directly impacting machine performance and fuel efficiency. This code is critical because it affects the excavator's ability to deliver precise hydraulic power to all functions—boom, arm, bucket, and swing operations.

Common Symptoms

When fault code E1044 is active, operators typically experience:

• Sluggish or inconsistent hydraulic response across all functions, particularly under load
• Warning light illumination on the instrument cluster (hydraulic system alert)
• Reduced engine power or automatic derate mode to prevent system damage
• Erratic pump noise or unusual whining sounds from the hydraulic pump area
• Increased fuel consumption due to improper pump regulation and system inefficiency

Potential Causes

The most common technical reasons for E1044 in used XCMG excavators include:

• Faulty proportional solenoid valve due to internal coil failure or mechanical wear
• Damaged wiring harness near the hydraulic pump mounting area where cables experience vibration and heat exposure
• Corroded or loose electrical connectors at the solenoid valve plug (common in machines with high operating hours)
• Short circuit or open circuit in the solenoid control wiring
• ECM internal fault or software calibration issues (less common)
• Low voltage supply from the machine's electrical system affecting solenoid operation

How to Troubleshoot and Fix Code E1044

Step 1: Visual Inspection Begin with a thorough examination of the solenoid valve connector and wiring harness routing from the ECM to the hydraulic pump. On used excavators, check for wire chafing against the pump housing, heat damage from exhaust components, and connector pin corrosion. Clean all connections with electrical contact cleaner.

Step 2: Electrical Testing Using a digital multimeter, check the solenoid coil resistance (typically 8-15 ohms, consult XCMG service manual for exact specifications). Test the supply voltage at the connector with the ignition on—it should read approximately 12-24V depending on your machine model. Check for continuity in the wiring between the ECM and solenoid.

Step 3: Component Testing and Replacement If resistance and voltage readings are within specification, perform a solenoid function test using XCMG diagnostic software to command the valve through its full range. If the solenoid fails to respond or produces erratic current draw, replacement is necessary. Before installing new components on used machines, thoroughly inspect the connector terminals and replace any corroded pins.

Disclaimer: This guide provides general troubleshooting information. Always consult the official XCMG service manual for your specific model and serial number. Complex hydraulic and electrical diagnostics should be performed by certified technicians with proper diagnostic equipment.