Doosan Excavator Fault Code E000108-09: Complete Diagnostic Guide

What is Doosan General Fault Code E000108-09?

Fault Code E000108-09 indicates a hydraulic pump pressure sensor circuit malfunction, specifically detecting an abnormal voltage signal from the main pump pressure sensor to the Electronic Control Module (ECM). This code is part of Doosan's electro-hydraulic monitoring system that ensures optimal hydraulic pressure regulation during excavator operation.

The pressure sensor continuously monitors main hydraulic pump output and sends analog voltage signals to the ECM. When the ECM detects voltage outside the normal operating range (typically 0.5-4.5 volts), it triggers E000108-09. This fault is critical because the ECM relies on accurate pressure data to adjust engine speed, regulate hydraulic flow, and prevent system damage. On used excavators, this code often appears due to sensor degradation, wiring harness wear, or connector corrosion—all common in machines with 3,000+ operating hours.

Common Symptoms

When Code E000108-09 is active, operators typically experience:

• Hydraulic system derate with noticeably reduced boom, arm, or bucket speed
• Intermittent power loss during high-demand operations like digging or lifting
• Warning light illumination on the instrument cluster (typically amber hydraulic icon)
• Erratic engine RPM fluctuations when activating hydraulic functions
• Error message display on digital monitor showing pressure system fault

Potential Causes

The most common technical causes for E000108-09 in used Doosan excavators include:

• Hydraulic pump pressure sensor failure due to internal component wear or contamination exposure
• Wiring harness damage at known rub points near the pump mounting area or along the main boom
• Corroded or loose electrical connectors at the sensor or ECM interface
• ECM voltage supply issues affecting the 5-volt reference circuit
• Contaminated hydraulic oil causing sensor membrane damage or calibration drift
• Previous repair attempts with incorrect sensor specifications or aftermarket parts

How to Troubleshoot and Fix Code E000108-09

Step 1: Initial Visual Inspection Begin by examining the hydraulic pump pressure sensor (typically located on the main control valve or pump body). Check for physical damage, oil contamination on the connector, or loose mounting. Inspect the wiring harness from sensor to ECM, focusing on areas where the harness contacts the frame, boom pivot points, or engine components—common wear locations on used machines.

Step 2: Electrical Testing Using a digital multimeter, perform voltage checks with the ignition on, engine off. Verify the 5-volt reference supply at the sensor connector (consult Doosan wiring diagrams for specific pin locations). Test sensor output voltage—it should read approximately 0.5-1.0 volts at zero pressure. Check for circuit resistance between sensor ground and chassis ground (should be less than 5 ohms). Corroded connectors often show elevated resistance readings.

Step 3: Dynamic Testing and Component Replacement Connect Doosan diagnostic software (DMS-5 or equivalent) to monitor live sensor data during engine operation. Compare actual pressure readings against commanded values. If voltage remains static or shows erratic spikes, replace the pressure sensor with OEM-specification parts. For used excavators, always replace the connector pigtail simultaneously, as pin corrosion frequently causes intermittent faults even with new sensors.

Step 4: System Verification After repairs, clear fault codes, operate all hydraulic functions under load, and monitor for code recurrence. Verify hydraulic oil cleanliness meets ISO 4406 standards (18/16/13 or better) to prevent premature sensor failure.

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Disclaimer: This guide provides general diagnostic information. Hydraulic system repairs involve high-pressure components and electrical systems. Always consult Doosan service manuals and consider professional technician assistance for complex diagnostics or if you lack proper tools and training.