Hitachi ZX870LCH-3 Fault Code 14106-2: Complete Diagnostic Guide

What is Hitachi ZX870LCH-3 Fault Code 14106-2?

Fault Code 14106-2 indicates a malfunction in the Engine Control Module (ECM) communication circuit, specifically a data link error or CAN bus communication failure between the engine controller and other machine systems. This code is part of Hitachi's proprietary diagnostic system for the ZX870LCH-3 excavator series.

This fault affects the Controller Area Network (CAN) communication protocol that allows the ECM, hydraulic controllers, and display monitors to exchange critical operational data. When communication breaks down, the machine cannot properly coordinate engine performance with hydraulic demands, potentially causing reduced efficiency or complete operational shutdown. For the ZX870LCH-3's advanced Isuzu engine management system, maintaining clean CAN bus communication is essential for optimal fuel economy and emissions control.

Common Symptoms

• Warning lights illuminated on the instrument cluster, particularly the engine malfunction indicator and communication error symbols
• Intermittent or complete loss of engine data display (RPM, coolant temperature, fuel level) on the monitor panel
• Engine derate mode activation, limiting power output to 50-70% of normal capacity
• Erratic hydraulic response or inability to match engine speed with hydraulic load demands
• Failure to start or unexpected engine shutdown during operation

Potential Causes

The most common technical causes for Code 14106-2 on used ZX870LCH-3 excavators include:

• CAN bus wiring harness damage from rubbing against the engine block or frame rails near the turbocharger area (known wear point on this model)
• Corroded or loose connector pins at the ECM or junction box locations, especially in machines operating in coastal or high-humidity environments
• Failed terminating resistor on the CAN network (typically 120-ohm resistors at network endpoints)
• ECM internal failure or corrupted software, more common in machines with 8,000+ operating hours
• Voltage irregularities from failing alternator or weak battery connections affecting communication signal integrity
• Aftermarket monitor or accessory installations that improperly tap into the CAN network

How to Troubleshoot and Fix Code 14106-2

Step 1: Visual Inspection Begin with a thorough physical examination of all wiring harnesses running from the ECM (located behind the operator cab) to the engine bay. On used excavators, pay special attention to harness routing near heat sources and moving components. Check all connector terminals for green corrosion, bent pins, or moisture intrusion. Clean connections with electrical contact cleaner and apply dielectric grease.

Step 2: CAN Bus Electrical Testing Using a digital multimeter, measure CAN-High and CAN-Low voltage at the ECM connector with the key in the ON position (engine off). You should read approximately 2.5V on each line at rest. Check for proper terminating resistance by measuring between CAN-High and CAN-Low terminals with all modules disconnected—you should read 60 ohms (two 120-ohm resistors in parallel).

Step 3: Diagnostic Software Analysis Connect Hitachi Dr.EX diagnostic software or compatible scan tool to retrieve freeze frame data and monitor live CAN bus traffic. Check for communication dropout patterns that indicate intermittent failures. Test the system while flexing harnesses to identify movement-related faults common in used machinery.

Step 4: Component Isolation Systematically disconnect non-essential CAN devices (aftermarket monitors, telematics) to identify if a faulty module is corrupting the network. If the code clears, reconnect devices one at a time to isolate the problematic component.

Step 5: Repair or Replace Replace damaged harness sections using OEM-spec shielded twisted-pair cable. Ensure proper grounding at all connection points. If the ECM is determined faulty, verify the replacement unit matches your machine's software version to avoid compatibility issues.

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Disclaimer: This guide provides general diagnostic information. Complex electrical issues on heavy equipment should be diagnosed by qualified technicians with proper training and equipment. Always consult the official Hitachi service manual and follow safety protocols when working on excavator electrical systems.