Doosan DX220LC-9C Fault Code E000174-00: Complete Diagnostic Guide

What is Doosan DX220LC-9C Fault Code E000174-00?

Fault Code E000174-00 indicates a Main Pump Control Solenoid Valve (SCV) circuit malfunction in the Doosan DX220LC-9C excavator's hydraulic system. This code specifically points to an electrical fault within the main pump regulator solenoid circuit, which controls hydraulic pump displacement and pressure based on load demands.

The Electronic Control Module (ECM) continuously monitors the solenoid valve's electrical parameters during operation. When voltage, current, or resistance values fall outside the manufacturer's specified range (typically 0.5-4.5V signal range), the system logs E000174-00. This is critical because the main pump SCV directly influences hydraulic flow delivery, affecting digging force, swing speed, and overall machine productivity. In the DX220LC-9C, this component is integral to the advanced Smart Power Control (SPC) system that optimizes fuel efficiency and hydraulic performance.

Common Symptoms

When fault code E000174-00 is active, operators typically experience:

• Reduced hydraulic power across all functions, with noticeably sluggish boom, arm, and bucket movements
• Erratic pump response during combined operations (e.g., swing while digging)
• Illuminated warning light on the instrument cluster, often accompanied by an audible alarm
• Engine over-revving without corresponding hydraulic speed increase due to improper pump displacement control
• Intermittent loss of power that may temporarily resolve after restarting the machine

Potential Causes

The most common technical causes for E000174-00 in used excavators include:

• Solenoid valve coil failure due to age-related insulation breakdown or moisture ingress (typical resistance: 10-15 ohms)
• Damaged wiring harness at known rub points near the main pump mounting area or along the right-hand chassis rail
• Corroded or loose connectors at the pump solenoid connector (common in machines with 5,000+ hours)
• ECM internal driver circuit failure, particularly in units exposed to electrical surges or improper jump-starting
• Hydraulic contamination causing the solenoid spool to stick, increasing electrical current draw beyond normal parameters

How to Troubleshoot and Fix Code E000174-00

Step 1: Initial Inspection Using Doosan DMS diagnostic software (or compatible scan tool), record freeze frame data and verify the fault is current, not historical. Visually inspect the main pump solenoid connector for corrosion, bent pins, or oil contamination. In used excavators, this connector often shows green corrosion due to moisture exposure.

Step 2: Electrical Testing Disconnect the solenoid valve connector and measure coil resistance using a quality digital multimeter—specification is typically 10-15 ohms at 20°C. Check for supply voltage at the harness side (should read 12V with key on). Measure ground circuit continuity to ensure less than 1 ohm resistance to chassis ground.

Step 3: Wiring Harness Verification Inspect the entire harness route from the ECM connector (located behind the operator seat) to the pump solenoid. Pay special attention to the harness section crossing the engine mount area—a known wear point on DX220LC-9C models. Check for wire insulation damage, especially on used machines with aftermarket engine work.

Step 4: Component Replacement and Verification If resistance or voltage readings are out of specification, replace the main pump solenoid valve (Doosan part reference: varies by serial number prefix). After replacement, clear codes using diagnostic software, operate the machine through full hydraulic cycles, and verify code does not return. For used excavators, always apply dielectric grease to connectors during reassembly to prevent future corrosion.

Disclaimer: This guide provides general diagnostic information. Always consult the official Doosan service manual for your specific serial number and seek qualified technician assistance for complex electrical repairs. Improper diagnostics may cause additional system damage.