What is Doosan DX380-9C Fault Code E000110-03?

Fault Code E000110-03 indicates a Hydraulic Pump Pressure Sensor Circuit Low Voltage condition on the Doosan DX380-9C excavator. This diagnostic trouble code (DTC) is triggered when the Electronic Control Unit (ECU) detects that the voltage signal from the main hydraulic pump pressure sensor has fallen below the manufacturer's specified threshold, typically below 0.5 volts.

This sensor continuously monitors the discharge pressure of the main hydraulic pumps and sends real-time data to the machine's controller. The ECU uses this information to regulate pump output, optimize hydraulic flow, and protect the system from over-pressurization or cavitation. On the DX380-9C, this sensor is critical for the machine's Electronic Pump Control (EPC) system, which directly affects digging force, swing speed, and overall hydraulic efficiency. When this code activates, the machine may enter a protective derate mode to prevent potential hydraulic system damage.

Common Symptoms

• Hydraulic power loss or significantly reduced digging and lifting force across all functions
• Warning light illuminated on the instrument cluster, often accompanied by an audible alarm
• Sluggish operation during multi-function work (e.g., boom lift combined with swing)
• Intermittent performance issues that worsen as the machine warms up or during high-demand operations
• Error message displayed on the monitor panel indicating hydraulic system fault

Potential Causes

The most common technical causes for E000110-03 on used DX380-9C excavators include:

• Damaged or corroded wiring harness between the pressure sensor and ECU, particularly at connector pins exposed to hydraulic oil mist or moisture
• Failed hydraulic pump pressure sensor due to internal circuit failure or diaphragm deterioration (common after 6,000+ operating hours)
• Chafed or pinched sensor wiring near the pump mounting area where harnesses contact frame members during engine vibration
• Corroded connector terminals at the sensor plug or ECU interface, especially on machines operated in coastal or high-humidity environments
• Low supply voltage from the ECU to the sensor caused by poor ground connections or ECU internal faults
• Hydraulic oil contamination causing sensor port blockage or internal damage

How to Troubleshoot and Fix Code E000110-03

Step 1: Visual Inspection Begin by locating the main hydraulic pump pressure sensor mounted on the pump discharge manifold. Inspect the sensor connector and wiring harness for obvious damage, oil contamination, corrosion, or loose connections. On used excavators, pay special attention to harness routing near moving components or heat sources. Check connector pins for bent terminals or green corrosion (copper oxidation).

Step 2: Electrical Testing Using a digital multimeter (DMM), disconnect the sensor and measure the supply voltage from the ECU at the harness connector. You should see approximately 5.0 volts DC on the supply wire with the ignition on. Next, check the ground circuit for continuity to chassis ground (should read less than 1 ohm resistance). If voltage or ground readings are out of specification, trace the harness back to the ECU, checking for breaks or shorts.

Step 3: Sensor Testing and Replacement With the sensor disconnected, measure its internal resistance across the signal and ground pins (typically 200-500 ohms when cold). Compare readings to Doosan specifications in the service manual. If the sensor tests faulty or readings are erratic, replace it with a genuine Doosan pressure sensor (Part# may vary by serial number). Before installing the new sensor, clean the mounting port thoroughly and apply thread sealant appropriate for hydraulic systems.

Step 4: System Verification After repairs, clear the fault code using Doosan diagnostic software (DMS) or a compatible diagnostic scanner. Operate the machine through all hydraulic functions while monitoring live sensor data. The pressure sensor should read 0-50 bar at idle and 300-350 bar under full load conditions. For used machines, verify that hydraulic oil quality meets specifications, as contaminated oil can cause repeat sensor failures.

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Disclaimer: This guide provides general troubleshooting information for the Doosan DX380-9C. Always consult the official Doosan service manual for your specific machine serial number and seek assistance from a certified heavy equipment technician for complex electrical diagnostics or hydraulic system repairs.