What is Hitachi ZX210LCK-5G Fault Code 14104-2?

Fault Code 14104-2 indicates an abnormal signal from the Hydraulic Pump Pressure Sensor, specifically detecting a voltage reading that is too low or an open circuit condition. This diagnostic trouble code (DTC) is generated when the Engine Control Module (ECM) receives a sensor signal below the manufacturer's specified threshold, typically under 0.5 volts, suggesting either a faulty sensor, damaged wiring, or poor electrical connections.

This code is critical for the ZX210LCK-5G because the hydraulic pump pressure sensor provides essential feedback to the ECM for optimizing engine performance and hydraulic efficiency. When this sensor fails or sends incorrect data, the machine cannot properly regulate hydraulic system demands, leading to reduced productivity and potential component damage. In used excavators, this fault commonly appears due to age-related electrical degradation, making early diagnosis essential.

Common Symptoms

When fault code 14104-2 is active, operators typically experience:

• Engine warning light or malfunction indicator lamp illuminated on the dashboard
• Reduced hydraulic power or sluggish boom/arm/bucket response during operation
• Engine derate mode activated, limiting RPM to protect the hydraulic system
• Erratic hydraulic system performance, especially during high-demand operations
• Stored fault code in the ECM memory accessible via diagnostic software

Potential Causes

The most common technical causes for code 14104-2 on used Hitachi excavators include:

• Failed hydraulic pump pressure sensor due to internal component wear or contamination
• Damaged or corroded wiring harness between the sensor and ECM, particularly at known rub points near the hydraulic pump mounting area
• Loose, corroded, or oil-contaminated electrical connectors at the sensor or ECM
• Open circuit caused by broken wires inside the insulation (common in high-vibration areas)
• Faulty ECM or poor ground connections affecting sensor voltage supply
• Previous repairs using incorrect wire gauge or non-OEM connectors in used machines

How to Troubleshoot and Fix Code 14104-2

Step 1: Visual Inspection Begin by inspecting the hydraulic pump pressure sensor located on the main hydraulic pump. Check for physical damage, oil contamination on connectors, or obvious wire chafing. On used excavators, examine harness routing for wear points where the harness contacts metal surfaces or moving components.

Step 2: Electrical Testing Using a digital multimeter, disconnect the sensor connector and measure the supply voltage from the ECM harness side. You should read approximately 5 volts DC. Next, check sensor resistance (typically 200-400 ohms when cold). Test for continuity between the sensor connector and ECM pins, and verify the ground circuit has less than 1 ohm resistance.

Step 3: Component Replacement and Verification If voltage supply is correct but sensor resistance is out of specification, replace the hydraulic pump pressure sensor with a genuine Hitachi part. For used machines with harness damage, repair or replace the affected section using proper gauge wire and heat-shrink connections. After repairs, clear codes using Hitachi Dr.EX diagnostic software or compatible scan tool, then operate the machine under load to verify the repair.

Disclaimer: This guide provides general troubleshooting information. Always consult the official Hitachi service manual for your specific serial number and seek qualified technician assistance for complex electrical diagnostics or hydraulic system repairs.