What is Doosan Excavator Fault Code E000168-01?

Fault Code E000168-01 indicates a communication error or data link failure between the Engine Control Module (ECM) and the Machine Controller (MC) on Doosan excavators. This diagnostic trouble code (DTC) is triggered when the ECM detects an interruption or abnormal signal in the Controller Area Network (CAN) bus communication system that connects critical electronic control units.

This fault is particularly critical for Doosan excavators because the ECM and Machine Controller must constantly exchange data to coordinate engine performance with hydraulic demands, monitor system parameters, and ensure safe operation. When communication breaks down, the machine's integrated control system cannot function properly, potentially leading to unexpected behavior or complete shutdown to prevent equipment damage.

Common Symptoms

When fault code E000168-01 is active, operators typically experience:

• Warning lights illuminated on the instrument cluster, often including the engine malfunction indicator and system error lights
• Reduced engine power or derate mode, where the excavator limits performance to protect components during communication failures
• Erratic hydraulic response or delayed control inputs due to disrupted coordination between engine and hydraulic systems
• Intermittent display malfunctions on the monitor panel, including missing data readings or frozen screens
• Engine shutdown or failure to start in severe cases where the ECM cannot verify safe operating conditions

Potential Causes

The most common technical causes for E000168-01 on used Doosan excavators include:

• Corroded or loose CAN bus connectors, especially at the ECM or Machine Controller connection points where moisture infiltration is common
• Damaged wiring harness with chafing or breaks in the twisted-pair CAN communication wires, particularly near articulation points or engine bay mounting brackets
• Faulty termination resistors on the CAN network (typically 120-ohm resistors at each network end)
• ECM or Machine Controller internal failure, though less common than wiring/connector issues in used machines
• Low voltage or unstable power supply affecting controller operation, often from aging batteries or failing alternators
• Aftermarket component interference from improperly installed accessories that disrupt the CAN network

How to Troubleshoot and Fix Code E000168-01

Step 1: Visual Inspection Begin by thoroughly inspecting all wiring harnesses between the ECM (typically located near the engine) and the Machine Controller (usually in the cab area). Look specifically for rubbed insulation, pinched wires at mounting points, or corroded connectors. On used excavators, pay special attention to harness routing where cables pass through the swing bearing area or near hydraulic lines where heat and vibration cause accelerated wear.

Step 2: Connector and Voltage Testing Disconnect the CAN bus connectors at both the ECM and Machine Controller. Inspect pins for corrosion, bent terminals, or moisture contamination—clean with electrical contact cleaner if needed. Using a digital multimeter, verify proper supply voltage (typically 12-24V depending on system) at controller power pins. Check for secure ground connections, as poor grounding is a frequent culprit in communication errors on older machines.

Step 3: CAN Network Resistance Check With controllers disconnected, measure resistance across the CAN-High and CAN-Low wires using your multimeter. You should read approximately 60 ohms with both termination resistors in place (two 120-ohm resistors in parallel). A reading of 120 ohms indicates one missing termination resistor; infinite resistance suggests an open circuit in the wiring.

Step 4: Advanced Diagnostics Connect Doosan diagnostic software (such as DMS-5 or equivalent dealer tool) to read detailed communication parameters and monitor real-time CAN bus traffic. This software can identify which specific controller is failing to communicate and may reveal intermittent connection issues not apparent during static testing. For used equipment, perform a "wiggle test" by gently moving harnesses while monitoring for communication dropouts.

Step 5: Component Replacement If wiring and connections test satisfactory, the fault likely resides within either the ECM or Machine Controller. Replace the termination resistors first if resistance values were incorrect (these are inexpensive and commonly fail). If the problem persists, professional controller diagnostics or replacement may be necessary—consider testing with known-good components if available before purchasing expensive control modules.

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Disclaimer: This guide provides general troubleshooting information for educational purposes. Always consult your Doosan service manual for model-specific procedures, torque specifications, and safety precautions. Complex electronic diagnostics should be performed by qualified technicians with appropriate training and equipment.