What is Hitachi ZX200-5G Fault Code 20113-2?

Fault Code 20113-2 on the Hitachi ZX200-5G excavator indicates a hydraulic pump solenoid circuit malfunction, specifically an open circuit or abnormal voltage condition in the proportional control solenoid valve system. This code is generated when the machine's controller (ECM) detects that the electrical signal to the main hydraulic pump regulator solenoid is outside the acceptable range, preventing proper pump displacement control.

This fault is critical because the ZX200-5G relies on electronic proportional control to match hydraulic pump output to operational demand. When this circuit fails, the excavator loses its ability to efficiently regulate hydraulic flow, directly impacting fuel economy, response time, and overall machine performance. In used machines, this code frequently appears due to degraded wiring harnesses or solenoid coil deterioration from heat cycling over thousands of operating hours.

Common Symptoms

• Reduced hydraulic power across all functions, with sluggish boom, arm, and bucket movements
• Illuminated engine/hydraulic warning light on the instrument cluster with simultaneous audible alarm
• Machine entering derate mode, limiting engine RPM to approximately 1,500-1,800 RPM
• Erratic hydraulic response or complete loss of fine control during precision operations
• Increased fuel consumption as the system defaults to maximum pump displacement

Potential Causes

The most common causes for Code 20113-2 on used ZX200-5G excavators include:

• Damaged wiring harness between the ECM and pump solenoid, particularly at the frame rail routing point where cable abrasion occurs
• Failed proportional solenoid coil within the main pump regulator assembly (typical resistance: 8-12 ohms)
• Corroded or loose connector pins at the pump-mounted solenoid plug, especially in machines operating in wet or corrosive environments
• ECM internal driver circuit failure, though less common than external wiring issues
• Intermittent short-to-ground caused by damaged insulation on the solenoid harness near hot engine components

How to Troubleshoot and Fix Code 20113-2

Step 1: Connect a Hitachi Dr.EX diagnostic tool or compatible scan tool to retrieve freeze frame data and verify Code 20113-2 is active. Record operating conditions when the fault occurred.

Step 2: Locate the main hydraulic pump solenoid on the left side of the pump assembly. Disconnect the electrical connector and inspect for corrosion, moisture intrusion, or damaged pins. Clean with electrical contact cleaner if necessary.

Step 3: Using a digital multimeter, measure solenoid coil resistance between the two solenoid terminals. You should read 8-12 ohms. If the reading shows infinite resistance (open circuit) or zero ohms (short), replace the solenoid valve assembly.

Step 4: If solenoid resistance is correct, perform a voltage supply test. With the key on and engine off, backprobe the connector to verify the ECM is supplying approximately 12 volts to the solenoid circuit. No voltage indicates an ECM driver issue or broken wire.

Step 5: On used excavators, physically trace the wiring harness from the ECM (located under the cab floor) to the pump solenoid. Pay special attention to areas where the harness contacts the frame, particularly near the swing bearing and along the right side engine mount. Look for wire insulation wear, exposed copper, or heat damage.

Step 6: Clear the fault code and operate the machine under load. If the code returns immediately, suspect an ECM internal fault; if it returns intermittently, focus on harness integrity and connector weatherproofing.

For used excavators specifically, always apply dielectric grease to repaired connectors and secure harnesses away from moving components using OEM-style clamps to prevent future recurrence.

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Disclaimer: This guide provides general troubleshooting information. Always consult the official Hitachi service manual for your specific machine serial number and consider professional diagnostic assistance for complex electrical issues or ECM replacement procedures.