What is Hitachi ZX210LCH-5G Fault Code 14107-2?

Fault Code 14107-2 on the Hitachi ZX210LCH-5G excavator indicates a Pilot Pressure Sensor Circuit Low Voltage condition. This code is triggered when the Engine Control Module (ECM) detects an abnormally low voltage signal from the pilot pressure sensor, which monitors the hydraulic pilot circuit pressure that controls implement and swing functions.

The pilot pressure sensor is critical for this Hitachi model's performance because it allows the ECM to optimize engine output based on operator demand. When the sensor circuit voltage drops below the manufacturer's specified threshold (typically below 0.5V), the system cannot accurately determine hydraulic load, potentially causing erratic machine behavior and reduced operational efficiency. On used ZX210LCH-5G excavators, this fault often stems from connector corrosion or harness damage rather than actual sensor failure.

Common Symptoms

When Code 14107-2 is active, operators typically experience:

• Engine derate or limited power output, particularly during combined hydraulic functions
• Erratic or sluggish hydraulic response when operating joysticks or pedals
• Intermittent warning light on the instrument cluster, sometimes accompanied by audible alarms
• Inconsistent engine RPM fluctuation under load, even with steady throttle input
• Diagnostic monitor displaying active fault when checked with service tools

Potential Causes

The most common technical causes for Code 14107-2 on used Hitachi excavators include:

• Corroded or loose connector pins at the pilot pressure sensor (located near the main control valve)
• Damaged wiring harness due to rubbing against the hydraulic tank or frame rails—a known wear point on ZX-5G series machines
• Failed pilot pressure sensor with internal circuit degradation from heat cycling and contamination exposure
• Shorted sensor ground wire or poor chassis ground connection causing voltage drop
• ECM internal fault (rare, but possible on high-hour used machines with electrical system history)
• Low voltage supply from corroded power distribution connectors in the engine compartment

How to Troubleshoot and Fix Code 14107-2

Step 1: Visual Inspection and Connector Check Begin by locating the pilot pressure sensor mounted on the main control valve assembly. Disconnect the sensor wiring harness connector and inspect for corrosion, moisture, or bent pins. On used excavators, this connector frequently shows green corrosion due to environmental exposure. Clean contacts with electrical contact cleaner and apply dielectric grease before reconnection.

Step 2: Voltage and Resistance Testing Using a digital multimeter (DMM), check the sensor supply voltage at the harness connector with the ignition on (should read approximately 5V). Then measure sensor resistance across the sensor terminals with ignition off (typical range: 100-500 ohms—consult service manual for exact specifications). Compare readings against Hitachi factory specifications using Dr.EX diagnostic software if available.

Step 3: Harness Continuity and Ground Verification Trace the sensor harness from the control valve to the ECM connector, checking for abrasion points where the harness passes near the hydraulic tank mounting bracket—a common failure location on ZX210 models. Perform continuity tests on all three wires (signal, ground, supply) and verify the chassis ground point has less than 0.5 ohms resistance. For used machines, replacing aged harness sections prevents recurring faults.

Step 4: Sensor Replacement and System Reset If testing confirms sensor failure, install a genuine Hitachi pilot pressure sensor (OEM part recommended for reliability). After replacement, clear the fault code using diagnostic software and perform a pressure calibration procedure following factory protocols. Monitor the system during a full operational cycle to confirm repair success.

---

Disclaimer: This guide provides general troubleshooting information. Always consult the official Hitachi service manual for your specific machine serial number and seek qualified technician assistance for complex electrical diagnostics or repairs involving safety-critical systems.