What is XCMG XE750D Fault Code 2417-5 SPN626 FMI5?

Fault Code 2417-5 (SPN626 FMI5) indicates a current below normal or open circuit condition in the J1939 data link communication system, specifically affecting the engine control module's (ECM) ability to maintain proper network communication. This fault code is critical because SPN 626 relates to the J1939 network voltage supply, and FMI 5 signifies that the circuit is drawing less current than expected or has an open connection.

For the XCMG XE750D excavator, this code directly impacts the CANbus communication network that allows the engine ECM, hydraulic controller, and display module to exchange critical operational data. When this communication link fails, the machine's integrated control systems cannot function properly, potentially causing complete system shutdowns or severe performance limitations. This is particularly problematic in used excavators where connector corrosion and harness wear are common issues.

Common Symptoms

• Red warning light illuminated on the instrument cluster with possible "Check Engine" or communication error messages
• Engine derating or limited power output, preventing the excavator from achieving full RPM or hydraulic flow
• Inoperative or frozen display screens showing outdated or no data from engine parameters
• Intermittent starting issues or complete failure to crank when communication between key control modules is lost
• Erratic hydraulic performance due to lack of coordination between engine load and hydraulic demand signals

Potential Causes

The most common technical causes for this fault code in used XCMG XE750D excavators include:

• Corroded or damaged J1939 network connectors, especially at bulkhead pass-throughs near the engine bay where moisture intrusion occurs
• Broken or chafed CANbus wiring harness, particularly at flex points around the swing bearing or boom pivot areas
• Failed 120-ohm terminating resistors at either end of the J1939 network causing improper signal termination
• Low battery voltage or poor grounding, affecting the 9-pin Deutsch connector supplying power to the communication network
• Defective ECM internal CANbus transceiver due to voltage spikes or water damage in older machines
• Aftermarket component installation that improperly tapped into the J1939 network without proper isolation

How to Troubleshoot and Fix Code 2417-5 SPN626 FMI5

Step 1: Visual Inspection and Voltage Verification Begin by inspecting all J1939 network connectors (typically green or yellow CANbus cables) for corrosion, bent pins, or moisture. Check battery voltage—it must be above 12.5V with the key off. Use a digital multimeter to verify that Pin 3 (CAN High) and Pin 11 (CAN Low) on the 9-pin diagnostic connector show approximately 2.5V each relative to ground with the key on, engine off.

Step 2: Resistance and Continuity Testing Disconnect the battery and measure resistance between CAN High and CAN Low terminals at the diagnostic port—you should read approximately 60 ohms (indicating both 120-ohm terminating resistors are present and functional). On used excavators, physically trace the harness from the ECM to the display module, checking for chafe points at cable ties, sharp edges, or areas where the harness contacts the frame during machine articulation.

Step 3: Advanced Diagnostics and Component Replacement Connect XCMG diagnostic software (or compatible J1939 scan tool) to monitor real-time CANbus traffic and identify which module is failing to communicate. If the harness and connectors test good, check terminating resistors by accessing them at the ECM and instrument cluster—replace any that measure open circuit or significantly higher than 120 ohms. For persistent issues, inspect the ECM CANbus transceiver circuit by monitoring for voltage spikes or checking for corrosion on ECM connector pins 24 and 42 (typical CANbus pins). In used machines, consider replacing the entire engine harness section if multiple repair attempts have been made, as internal wire degradation may not be visible externally.

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Disclaimer: This guide provides general troubleshooting information for educational purposes. Always consult the official XCMG service manual and consider professional diagnostic assistance for complex electrical issues. Improper repairs to communication networks can cause additional fault codes or damage to control modules.