Doosan DX150LC-9C Fault Code E000736-06: Complete Diagnostic Guide

What is Doosan DX150LC-9C Fault Code E000736-06?

Fault Code E000736-06 indicates a boom swing priority solenoid valve circuit malfunction in the Doosan DX150LC-9C excavator's hydraulic control system. This code is triggered when the Electronic Control Module (ECM) detects an abnormal voltage or current reading from the boom swing priority solenoid valve, which regulates hydraulic flow priority during combined boom and swing operations.

This fault is critical for the DX150LC-9C's performance because the boom swing priority system ensures smooth, coordinated movements during excavation work. When this circuit malfunctions, the excavator's productivity and operator control are significantly compromised, potentially leading to jerky movements or reduced operational efficiency in this popular mid-size excavator model.

Common Symptoms

When fault code E000736-06 is active, operators typically experience:

• Hydraulic movement warning light illuminated on the instrument cluster with code displayed on the monitor
• Erratic or sluggish boom swing performance during combined operations (boom lift + swing)
• Loss of priority control, causing the boom or swing function to feel inconsistent or unresponsive
• Intermittent hydraulic response when attempting simultaneous boom and swing movements
• Reduced cycle times during production work due to compromised hydraulic coordination

Potential Causes

The most common technical causes for E000736-06 in used DX150LC-9C excavators include:

• Solenoid valve coil failure due to normal wear, overheating, or electrical degradation over operational hours
• Wiring harness damage at known rub points near the main control valve assembly or along the right-hand chassis rail
• Corroded or loose electrical connectors on the solenoid valve plug, especially on machines with high moisture exposure
• Short circuit or open circuit in the harness between the ECM and the boom swing priority solenoid
• ECM internal driver circuit failure (less common, but possible in high-hour machines)
• Voltage supply issues from the main power distribution causing insufficient solenoid activation voltage

How to Troubleshoot and Fix Code E000736-06

Step 1: Visual Inspection Begin by accessing the main control valve assembly located beneath the operator's cab. Inspect the boom swing priority solenoid valve and its electrical connector for obvious damage, oil contamination, or corrosion. On used excavators, pay special attention to connector pins—corrosion is common in this location due to hydraulic oil mist exposure.

Step 2: Electrical Testing Using a digital multimeter (DMM), disconnect the solenoid connector and measure coil resistance. The boom swing priority solenoid should read approximately 3-7 ohms (consult service manual for exact specifications). Check for continuity to ground—any reading indicates a short circuit. Inspect the wiring harness for damage along known wear points where the harness contacts the frame near the swing bearing.

Step 3: Circuit Voltage Testing With the ignition on and connector attached, back-probe the solenoid connector using your DMM. You should read approximately 12-14 volts when the system commands the solenoid active. No voltage indicates a harness open circuit or ECM driver failure. Use Doosan DMS-5 diagnostic software to command the solenoid on/off and monitor real-time voltage feedback.

Step 4: Component Replacement If testing confirms solenoid failure, replace the boom swing priority solenoid valve with a genuine Doosan or OEM-equivalent part. Before installation on used machines, clean all connector contacts with electrical contact cleaner and apply dielectric grease to prevent future corrosion. If harness damage is found, repair using proper gauge wire and heat-shrink connections, ensuring routing avoids previous rub points.

Step 5: Clear Code and Verify After repairs, clear the fault code using diagnostic software and operate the machine through multiple combined boom-swing cycles. Monitor for code reoccurrence and verify smooth hydraulic priority function has been restored.

---

Disclaimer: This guide provides general diagnostic information for fault code E000736-06. Hydraulic and electrical system repairs should be performed by qualified technicians with proper training and tools. Always consult the official Doosan service manual for your specific machine serial number and follow all safety procedures when working on excavator systems.