What is Hitachi ZX870LC-5A Fault Code 20113-2?

Fault Code 20113-2 on the Hitachi ZX870LC-5A indicates a malfunction in the Engine Control Module (ECM) communication circuit, specifically a data link error between the ECM and the main controller. This diagnostic trouble code (DTC) signals that the engine's electronic control unit is experiencing interrupted or corrupted communication with the machine's primary monitoring system.

This code is critical for the ZX870LC-5A's operation because the ECM relies on continuous data exchange to regulate fuel injection timing, throttle response, and emission controls. When communication fails, the excavator's onboard diagnostics cannot properly monitor engine parameters, potentially leading to reduced performance, inefficient fuel consumption, or complete engine shutdown. For used excavators, this fault often emerges due to aging wiring harnesses or corroded connector pins in the CAN bus communication network.

Common Symptoms

When Code 20113-2 is active on your Hitachi ZX870LC-5A, operators typically experience:

• Engine warning light illuminated on the dashboard with possible error message display
• Intermittent engine derate or sudden power loss during operation
• Engine may fail to start or exhibits delayed cranking response
• Erratic throttle response or inconsistent RPM control
• Loss of real-time monitoring data on the instrument cluster (temperature, pressure readings showing dashes or zeros)

Potential Causes

The most common technical reasons for Code 20113-2 appearing on used ZX870LC-5A excavators include:

• Damaged or corroded CAN bus wiring harness between ECM and main controller (check harness routing near engine mounting points where vibration causes wear)
• Loose or oxidized connector terminals at the ECM connector pins (particularly C1 and C2 connectors)
• Failed ECM relay or intermittent power supply to the engine control module
• Internal ECM circuit board failure due to moisture intrusion or component aging
• Faulty main controller module unable to properly receive/transmit data packets
• Voltage irregularities from failing alternator or weak battery causing communication dropouts

How to Troubleshoot and Fix Code 20113-2

Step 1: Visual Inspection of Harnesses and Connectors Begin by inspecting all wiring harnesses between the ECM (located near the engine firewall) and the main controller. Look for abraded insulation, pinched wires at cable routing points, or evidence of rodent damage. On used machines, pay special attention to harness sections that cross vibration-prone areas or contact metal surfaces.

Step 2: Test Connector Integrity Disconnect the ECM connectors and inspect pins for corrosion, bent terminals, or moisture. Clean contacts with electrical contact cleaner and apply dielectric grease. Use a multimeter to verify continuity in the CAN-High and CAN-Low communication wires (typically found on pins specified in the service manual). Resistance should be approximately 60 ohms across the CAN bus termination.

Step 3: Verify Power Supply and Ground Circuits With connectors reinstalled, use a multimeter to check voltage at the ECM power supply pins (should read 24V DC with key on). Test ground circuits for resistance less than 1 ohm. Weak grounds are common in used excavators due to corrosion at grounding points.

Step 4: Diagnostic Software Analysis Connect Hitachi Dr.EX diagnostic software or compatible scan tool to read live data streams and freeze frame data. Monitor communication status between modules. If communication is intermittent, perform a "wiggle test" on harnesses while monitoring to identify movement-related faults.

Step 5: Component Replacement If diagnostics confirm ECM or controller failure, replacement may be necessary. For used excavators, consider sourcing remanufactured ECMs with updated firmware that addresses known communication vulnerabilities in earlier ZX870LC-5A production units.

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Disclaimer: This guide provides general troubleshooting information for Code 20113-2. Always consult the official Hitachi service manual for your specific machine serial number and seek professional assistance from certified Hitachi technicians for complex electrical diagnostics and ECM programming procedures.