XCMG Excavator Fault Code E1024: Complete Diagnostic Guide

What is XCMG General Fault Code E1024?

XCMG Fault Code E1024 indicates a communication error between the Engine Control Module (ECM) and the Hydraulic Control Unit (HCU), or a failure in the CAN bus data transmission system. This code typically appears when the main controller cannot receive proper signals from the hydraulic system's electronic control unit, disrupting the coordinated operation between engine power output and hydraulic demand.

This fault is critical for XCMG excavators because the ECM and HCU must constantly communicate to optimize fuel efficiency, prevent engine overload, and maintain precise hydraulic control. When this communication link fails, the machine's integrated control system cannot properly match engine speed to hydraulic flow requirements, compromising both performance and component longevity.

Common Symptoms

When Code E1024 is active, operators typically experience:

• Warning light illuminated on the instrument cluster, often with reduced engine power message
• Engine derate mode activated, limiting RPM to approximately 1400-1600 to protect components
• Sluggish hydraulic response with delayed boom, arm, or bucket movements despite throttle input
• Intermittent loss of auxiliary hydraulic functions including breaker or grapple attachments
• Error messages on the digital display showing communication fault or system malfunction

Potential Causes

The most common technical reasons for E1024 in XCMG excavators include:

• CAN bus wiring damage from harness chafing against the frame near the counterweight area (known wear point on used machines)
• Corroded or moisture-contaminated connectors on the HCU harness, particularly the 38-pin main connector
• Faulty terminating resistor on the CAN bus network (120-ohm resistor failure)
• ECM or HCU internal failure due to voltage spikes or water intrusion in older units
• Damaged shielding on twisted-pair CAN wires allowing electromagnetic interference from starter cables

How to Troubleshoot and Fix Code E1024

Step 1: Visual Harness Inspection Begin by inspecting the wiring harness routing between the ECM (located near the engine) and the HCU (typically mounted under the operator's cab). Check for abraded insulation, particularly where harnesses pass through bulkheads or near moving components. On used excavators, inspect connector boots for cracking and pins for corrosion.

Step 2: CAN Bus Resistance Testing Using a digital multimeter, disconnect both the ECM and HCU connectors. Measure resistance between the CAN-High and CAN-Low terminals—you should read approximately 60 ohms with both terminating resistors in circuit. If you read open circuit or incorrect values, check individual terminating resistors at each module.

Step 3: Voltage and Signal Verification With the key on (engine off), measure voltage on the CAN bus lines—both should show approximately 2.5V relative to ground. Start the engine and use XCMG diagnostic software or a compatible scan tool to monitor CAN bus activity. If messages show intermittent communication, perform a "wiggle test" on harnesses while monitoring to identify loose connections.

Step 4: Component-Level Testing If wiring and resistance checks pass, test power supply to the HCU. Verify battery voltage (12-14V) on the power pins and clean ground connections. For used machines, remove and inspect connectors for green corrosion inside the pins—clean with electrical contact cleaner and apply dielectric grease. Replace connectors showing melted plastic or backed-out pins.

Professional Note: This diagnostic procedure addresses common field failures. However, internal ECM or HCU failures require specialized dealer-level diagnostics and programming. Always consult XCMG service documentation and consider professional assistance for complex electrical issues, especially when replacing control modules that may require software calibration.