What is Doosan DX220LC-9C Fault Code E000105-03?

Fault Code E000105-03 indicates a hydraulic pump pressure sensor circuit malfunction, specifically a voltage signal that is out of the expected range or intermittent. This code is generated when the Electronic Control Unit (ECU) detects abnormal voltage readings from the main hydraulic pump pressure sensor, which monitors system pressure to optimize engine load and hydraulic performance.

On the DX220LC-9C excavator, this sensor is critical for the machine's Auto Power Control System, which automatically adjusts engine output based on hydraulic demand. When this code triggers, the ECU cannot accurately read hydraulic pressure, potentially causing the machine to operate in a derated power mode or fail to match engine speed to workload efficiently. For used excavators, this fault often stems from electrical degradation rather than actual sensor failure.

Common Symptoms

• Warning lamp illumination on the instrument cluster, often with reduced machine responsiveness
• Loss of automatic power matching, causing the engine to over-rev or lag during hydraulic operations
• Intermittent power loss or hesitation when operating multiple hydraulic functions simultaneously
• Increased fuel consumption due to improper engine-hydraulic coordination
• Error code storage in the ECU memory even after the issue seems resolved

Potential Causes

The most common causes for E000105-03 on used DX220LC-9C excavators include:

• Corroded or loose connector pins at the pressure sensor harness (located near the main hydraulic pump)
• Damaged sensor wiring due to vibration or chafing against the pump housing—a known wear point on machines with 3,000+ hours
• Failed hydraulic pump pressure sensor (Doosan part typically rated for 5V reference signal)
• ECU voltage supply issues, including poor grounding at the main harness ground point behind the cab
• Contaminated sensor face from hydraulic oil leaks causing false readings
• Water intrusion into the sensor connector, common on machines stored outdoors

How to Troubleshoot and Fix Code E000105-03

Step 1: Visual Inspection Access the main hydraulic pump area (left side of engine compartment). Inspect the pressure sensor connector for corrosion, bent pins, or oil contamination. Check the wiring harness for visible damage or rub-through points where it contacts the pump housing.

Step 2: Electrical Testing Using a digital multimeter, backprobe the sensor connector with the key on, engine off. Verify 5V reference voltage from the ECU and check for proper ground continuity (less than 0.5 ohms resistance). Measure the sensor's output signal—it should read approximately 0.5-4.5V depending on system pressure.

Step 3: Sensor and Harness Verification Disconnect the sensor and measure its internal resistance (typically 250-350 ohms for Doosan sensors). If readings are out of spec or open circuit, replace the sensor. For used excavators, always inspect the harness routing—secure any loose wiring away from vibration points using OEM-style clips.

Step 4: Clear Codes and Test Use Doosan DMS diagnostic software or a compatible scan tool to clear fault codes. Operate the machine through various hydraulic functions while monitoring live sensor data. If the code returns, inspect the ECU harness connector (C101) for corrosion—a common issue on 2015-2017 model year machines.

Disclaimer: This guide provides general troubleshooting information. Always consult the official Doosan service manual and consider professional diagnostic assistance for complex electrical issues. Improper repairs may cause further damage or safety hazards.