What is Doosan DX215-9C Fault Code E000110-01 (P1118)?

Fault Code E000110-01 (P1118) indicates an Engine Coolant Temperature (ECT) sensor circuit high voltage condition in the Doosan DX215-9C excavator. This diagnostic trouble code is triggered when the Engine Control Module (ECM) detects an abnormally high voltage signal from the coolant temperature sensor, typically exceeding 4.8-4.9 volts for more than 0.5 seconds.

The ECT sensor plays a critical role in the DX215-9C's Doosan DL08 engine management system. It provides real-time coolant temperature data that the ECM uses to adjust fuel injection timing, idle speed, and activate cooling fan operation. When this circuit fails high, the ECM cannot accurately monitor engine temperature, potentially leading to overheating conditions, improper fuel delivery, and reduced engine protection.

Common Symptoms

• Check Engine Light or malfunction indicator lamp illuminated on the instrument cluster
• Engine may experience hard starting or extended cranking, especially in cold conditions
• Erratic cooling fan operation, with fans running continuously or not engaging at proper temperatures
• Possible engine derate or power reduction as the ECM enters a fail-safe mode
• Black smoke from the exhaust due to incorrect fuel mapping based on assumed temperature values

Potential Causes

The high voltage reading typically indicates an open circuit condition in the ECT sensor system. Common causes specific to used DX215-9C excavators include:

• Failed ECT sensor with internal open circuit (most common on machines with 5,000+ hours)
• Broken or corroded wiring in the sensor harness, particularly near the engine block where vibration and heat cycling cause wire fatigue
• Damaged connector pins at the ECT sensor plug—corrosion and moisture intrusion are frequent issues in the engine compartment
• Chafed wiring harness rubbing against the engine block or hydraulic lines (known issue on this model near the thermostat housing)
• Rare: ECM internal fault in the sensor input circuit

How to Troubleshoot and Fix Code E000110-01 (P1118)

Step 1: Visual Inspection Locate the ECT sensor on the front left side of the engine block near the thermostat housing. Inspect the sensor connector for corrosion, bent pins, or moisture. Check the wiring harness for obvious damage, chafing, or breaks, paying special attention to areas where the harness contacts metal surfaces.

Step 2: Sensor Resistance Testing Disconnect the ECT sensor connector. Using a digital multimeter, measure resistance across the sensor terminals. At 68°F (20°C), resistance should read approximately 2,500-3,000 ohms. At 176°F (80°C), it should drop to 300-350 ohms. An infinite (OL) reading confirms sensor failure.

Step 3: Circuit Voltage Check With the sensor disconnected and ignition ON (engine OFF), measure voltage at the ECM-side harness connector. You should read approximately 5 volts on the signal wire. If voltage is absent or incorrect, trace the harness back to the ECM for breaks or shorts.

Step 4: Harness Continuity Test Check continuity between the sensor connector and ECM pins (refer to Doosan service manual for specific pin locations). Also verify the ground circuit has less than 1 ohm resistance to chassis ground.

Step 5: Replacement and Verification For used excavators, always inspect connector terminals for corrosion and apply dielectric grease before reinstalling. Replace the ECT sensor with a genuine Doosan part (P/N: 65.05603-0062A recommended). Clear codes using Doosan DMS diagnostic software or compatible scan tool and verify repair during a complete heat cycle.

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Disclaimer: This guide provides general diagnostic information. Always consult the official Doosan service manual for your specific machine serial number and seek professional assistance if you're uncertain about any electrical diagnosis or repair procedures.