What is Hitachi ZX170W-3 Fault Code 13310-2?

Fault Code 13310-2 indicates a hydraulic pump solenoid circuit malfunction in the Hitachi ZX170W-3 wheeled excavator. This diagnostic trouble code (DTC) is triggered when the Electronic Control Module (ECM) detects an abnormal voltage or current signal in the hydraulic pump control solenoid circuit, specifically related to the pump's flow control system.

This code directly affects the machine's hydraulic pump delivery control, which regulates hydraulic flow based on operational demand. The ZX170W-3 uses an electronically controlled variable displacement pump, and when this circuit fails, the excavator cannot properly modulate hydraulic power. This results in reduced performance, inefficient fuel consumption, and potential damage to the hydraulic system if left unaddressed.

Common Symptoms

When Code 13310-2 is active on your ZX170W-3, operators typically experience:

• Hydraulic system operating at reduced power or sluggish response in boom, arm, and bucket movements
• Warning light illuminated on the instrument panel (typically a hydraulic or system error indicator)
• Engine RPM fluctuations during hydraulic operations due to improper load sensing
• Excessive fuel consumption as the pump fails to adjust flow efficiently
• Intermittent loss of hydraulic function or erratic pump behavior during warm-up or under load

Potential Causes

The most common technical causes for Code 13310-2 on used ZX170W-3 excavators include:

• Damaged or corroded wiring harness at the pump solenoid connector, especially where the harness runs near the pump body (known wear point)
• Failed hydraulic pump solenoid valve due to internal coil breakdown or mechanical sticking
• Poor ground connection at the pump or ECM mounting points, common in machines with 5,000+ operating hours
• ECM internal circuit failure or corrupted software (less common but possible in older units)
• Contaminated hydraulic oil causing solenoid valve sticking or electrical resistance changes
• Water intrusion in connectors from improper washing or damaged seals around the pump area

How to Troubleshoot and Fix Code 13310-2

Step 1: Visual Inspection of Wiring and Connectors Begin by inspecting the pump solenoid wiring harness for physical damage, particularly where it passes over the pump housing. On used excavators, check for harness rubbing, cracked insulation, or oil contamination. Disconnect the solenoid connector and examine pins for corrosion or bent terminals—a common issue after years of vibration and exposure.

Step 2: Test Solenoid Resistance and Voltage Using a digital multimeter, measure the solenoid coil resistance at the pump-side connector (disconnected). Typical specification is 15-25 ohms at room temperature; consult your service manual for exact values. Next, with ignition on and connector attached, back-probe the circuit to verify 12-24V supply voltage from the ECM during pump operation.

Step 3: Check Ground Circuit Integrity Verify the ground circuit at both the pump mounting and ECM ground points. Corrosion or loose bolts here frequently cause intermittent codes on used machines. Clean all ground surfaces with a wire brush and apply dielectric grease.

Step 4: Diagnostic Software Analysis Connect Hitachi Dr.EX diagnostic software or compatible scan tool to read real-time solenoid command signals. Compare ECM output commands with actual solenoid response. If commands are present but solenoid doesn't respond, replace the solenoid valve assembly.

Step 5: Component Replacement and Verification If resistance is out of spec or voltage is absent, replace the faulty component (wiring harness, solenoid, or address ECM issues). For used excavators, always replace connector seals and apply protective boots to prevent future moisture intrusion. After repairs, clear codes, run the machine through full hydraulic cycles, and verify code does not return.

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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 consult qualified technicians for complex electrical or hydraulic repairs. Improper diagnostics can lead to component damage or safety hazards.