What is Doosan Excavator Fault Code E000105-10?

Fault Code E000105-10 indicates a communication error between the Engine Control Module (ECM) and the Monitor Control Unit (MCU) on Doosan excavators. This diagnostic trouble code (DTC) specifically signals that the ECM has detected an abnormal or interrupted CAN bus communication signal with the machine's main display and monitoring system.

The CAN (Controller Area Network) bus is the digital communication backbone that allows the engine controller, hydraulic systems, and operator display to exchange critical data in real-time. When this communication link fails or becomes intermittent, the ECM triggers E000105-10 to alert operators that system integration has been compromised. This is particularly critical on Doosan machines because the MCU controls vital operator feedback, warning systems, and diagnostic displays—without proper communication, the machine cannot accurately report engine parameters, hydraulic temperatures, or other safety-critical information.

Common Symptoms

When fault code E000105-10 is active, operators typically experience:

• Blank or flickering monitor display with intermittent or complete loss of gauge readings
• Engine warning light illuminated on the dashboard, often accompanied by audible alarms
• Loss of real-time data including engine RPM, coolant temperature, fuel level, and hydraulic oil temperature readings
• Inability to access diagnostic menus or change machine settings through the monitor
• Intermittent machine operation where the display works temporarily then fails again during operation

Potential Causes

The most common technical reasons for E000105-10 on used Doosan excavators include:

• CAN bus wiring harness damage from rubbing against frame components, particularly near the engine firewall and cab mounting points
• Corroded or loose connector pins at the ECM or MCU harness connections due to moisture intrusion or vibration
• Failed terminating resistor on the CAN bus network causing signal reflection and communication errors
• ECM or MCU internal failure, though less common than wiring issues in used equipment
• Low battery voltage or poor ground connections affecting digital communication signal integrity
• Aftermarket component interference from improperly installed accessories that disrupt CAN bus signals

How to Troubleshoot and Fix Code E000105-10

Step 1: Visual Inspection of Harnesses and Connectors Begin by inspecting all wiring between the ECM (typically located near the engine) and the MCU (in the operator cab). Look specifically for harness rub points where the cable passes through the cab frame or near hydraulic lines. Check all CAN bus connectors for bent pins, corrosion (green/white residue), or moisture. On used excavators, pay special attention to areas where harnesses flex during cab rotation or boom movement.

Step 2: Electrical Testing of CAN Bus Circuit Using a digital multimeter, measure the CAN-High and CAN-Low resistance between the ECM and MCU connectors with the key off and harnesses disconnected. You should read approximately 60 ohms across the CAN bus terminating resistors. Check for continuity on each wire individually and verify no short to ground (reading should be infinite resistance to chassis ground). Voltage checks with key on should show approximately 2.5V on each CAN line with small fluctuating signals during communication.

Step 3: Advanced Diagnostics with Scan Tools Connect Doosan DMS (Diagnostic Master System) or compatible diagnostic software to monitor live CAN bus traffic. Watch for communication dropouts or error frames that indicate intermittent failures. If available, perform a CAN bus termination test through the software. For used excavators with unknown maintenance history, consider testing with a known-good MCU to eliminate display unit failure before replacing expensive ECM components.

Step 4: Repair and Verification Address identified issues by repairing damaged harnesses with proper CAN bus-rated wire (twisted pair, shielded), cleaning corroded connectors with electrical contact cleaner, and applying dielectric grease to prevent future moisture issues. Replace any damaged terminating resistors. After repairs, clear the fault code and operate the machine through multiple temperature cycles to ensure the communication remains stable.

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Professional Disclaimer: This guide provides general troubleshooting information for experienced technicians. CAN bus diagnostics require specialized knowledge and tools. Always consult the official Doosan service manual for your specific model and serial number. If you're uncomfortable performing electrical diagnostics on used excavators, contact a certified Doosan technician to prevent further damage to electronic components.