What is Hitachi ZX350LCK-5G Fault Code 11007-2?

Fault Code 11007-2 indicates a Hydraulic Pump Solenoid Circuit Malfunction - specifically an open circuit or high resistance condition in the main hydraulic pump control solenoid valve wiring. This code is triggered when the Engine Control Module (ECM) detects abnormal electrical resistance or a complete break in the circuit controlling the hydraulic pump's variable displacement mechanism.

On the ZX350LCK-5G excavator, this solenoid regulates the swash plate angle of the main hydraulic pump, directly controlling hydraulic flow and pressure. When this circuit fails, the excavator cannot properly modulate hydraulic power, severely impacting all machine functions including boom, arm, bucket, and swing operations. This is critical because the ZX350LCK-5G relies on precise electronic-over-hydraulic control for optimal fuel efficiency and performance.

Common Symptoms

• Reduced hydraulic power across all functions, with noticeably sluggish boom and arm movements
• Warning light illumination on the instrument cluster, often accompanied by an audible alarm
• Erratic pump operation where hydraulic response becomes inconsistent or unpredictable
• Engine rpm fluctuations during hydraulic operations as the ECM attempts to compensate
• Machine may enter derate mode, limiting engine power to prevent damage

Potential Causes

The most common technical causes for Code 11007-2 on used ZX350LCK-5G excavators include:

• Wiring harness damage near the pump mounting area where vibration and heat cause insulation breakdown
• Corroded or loose connector pins at the solenoid valve plug, especially on machines operating in wet or corrosive environments
• Failed hydraulic pump solenoid coil due to age-related deterioration or thermal stress
• Chafed wiring where the harness contacts the pump housing or frame rails—a known wear point on this model
• ECM internal fault (less common) affecting the solenoid driver circuit
• Poor ground connections at the pump assembly or chassis ground points

How to Troubleshoot and Fix Code 11007-2

Step 1: Visual Inspection Disconnect the battery and thoroughly inspect the solenoid valve wiring harness from the ECM to the pump. On used excavators, check for abraded insulation, melted wires, or oil contamination around the pump area. Examine the connector at the solenoid valve for bent pins, corrosion, or moisture intrusion.

Step 2: Electrical Testing Using a digital multimeter, measure resistance across the solenoid coil terminals (typically 10-30 ohms when functioning properly—consult service manual for exact specifications). Test continuity from the ECM connector to the solenoid valve. Check for short circuits to ground by measuring resistance between each wire and chassis ground (should read infinite resistance).

Step 3: Connector and Ground Verification Clean all connector pins with electrical contact cleaner and apply dielectric grease. Verify the pump assembly ground strap has less than 0.5 ohms resistance to chassis. On older machines, corrosion at ground points is extremely common and easily overlooked.

Step 4: Component Replacement If testing confirms solenoid coil failure, replace the proportional solenoid valve assembly. If wiring damage is found, repair using OEM-spec wire and protect with proper loom and heat shielding. For harness issues near known rub points, reroute slightly and secure with new clamps.

Step 5: Clear Codes and Test After repairs, use Hitachi Dr.EX diagnostic software or compatible scan tool to clear fault codes. Operate the machine through full hydraulic cycles while monitoring for code 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. If unfamiliar with high-pressure hydraulic systems or electrical diagnostics, consult a certified Hitachi technician to prevent injury or further damage.