What is Hitachi ZX350LCK-5G Fault Code 13310-3?

Fault Code 13310-3 on the Hitachi ZX350LCK-5G indicates a malfunction in the hydraulic pump control system, specifically related to abnormal current detection in the pump solenoid proportional valve circuit. This code is triggered when the Engine Control Module (ECM) detects an electrical current outside the acceptable range for the pump's proportional control valve, which regulates hydraulic flow and pressure throughout the excavator's systems.

This fault is critical because the hydraulic pump is the heart of excavator operation. The proportional solenoid valve modulates pump displacement based on operator demand and engine load. When the ECM cannot properly communicate with or control this valve due to current irregularities, the machine's hydraulic performance becomes compromised, potentially leading to reduced productivity or complete operational shutdown on this Isuzu-powered ZX350LCK-5G model.

Common Symptoms

• Reduced hydraulic power across all functions (boom, arm, bucket, swing) with noticeably sluggish response times
• Intermittent or constant warning light on the instrument cluster indicating hydraulic system malfunction
• Engine auto-derating to protect the drivetrain when the ECM enters fail-safe mode
• Erratic hydraulic performance where functions operate normally then suddenly lose power
• Audible changes in pump noise or unusual whining sounds from the main hydraulic pump area

Potential Causes

The most common causes of Code 13310-3 on used ZX350LCK-5G excavators include:

• Damaged or corroded wiring harness between the ECM and pump solenoid valve, particularly at flex points near the pump mounting area where vibration causes wire chafing
• Failed proportional solenoid valve within the hydraulic pump assembly due to internal coil degradation or contamination
• Connector corrosion at the pump solenoid connector, especially on machines with high operating hours in wet or dusty environments
• Shorted or open circuit in the solenoid valve wiring caused by pinched cables during previous maintenance
• ECM internal fault (less common) preventing proper current supply regulation to the pump control circuit

How to Troubleshoot and Fix Code 13310-3

Step 1: Visual Inspection Begin with a thorough inspection of the wiring harness running from the main ECM (located in the cab area) to the hydraulic pump solenoid valve. On used excavators, carefully examine all connector pins for corrosion, bent contacts, or moisture intrusion. Check for harness damage at common rub points—particularly where cables route over the engine block and near the pump mounting bracket.

Step 2: Electrical Testing Using a quality digital multimeter, disconnect the pump solenoid connector and measure resistance across the solenoid coil terminals. Typical specification is 3-7 ohms (consult your service manual for exact values). Then check for voltage supply from the ECM connector with ignition on—you should see battery voltage (approximately 24V on this model). Test for shorts to ground by measuring resistance between each solenoid wire and chassis ground (should read infinite resistance).

Step 3: Advanced Diagnostics Connect Hitachi Dr.EX diagnostic software or compatible scan tool to read live data parameters. Monitor the commanded current versus actual current to the pump solenoid during operation. A discrepancy indicates either solenoid failure or ECM output problems. For used machines, perform a wiggle test on connectors and harnesses while monitoring live data to identify intermittent connection issues common in high-hour equipment.

Step 4: Component Replacement If testing confirms solenoid failure, replacement requires partial pump disassembly. When installing new components on used excavators, always apply dielectric grease to connectors and secure harnesses away from heat and moving parts to prevent recurrence. Clear codes and perform a complete hydraulic system function test under load.

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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 diagnosis for complex electrical or hydraulic issues, especially when warranty or safety concerns exist.