What is Doosan DX215-9C Fault Code E000106-06 (P1112)?

Fault Code E000106-06 (P1112) indicates an Intake Air Temperature (IAT) Sensor High Voltage condition on the Doosan DX215-9C excavator. This code triggers when the Engine Control Module (ECM) detects a voltage signal from the IAT sensor that exceeds the manufacturer's specified threshold, typically above 4.8-5.0 volts.

The IAT sensor monitors incoming air temperature in the intake manifold, allowing the ECM to calculate optimal fuel injection timing and air-fuel ratios. On the DX215-9C's Doosan DL06P diesel engine, this sensor is critical for combustion efficiency, emissions control, and maintaining proper engine performance. When voltage reads abnormally high, the ECM interprets this as an extremely cold air temperature (often below -40°F), which is physically impossible during normal operation, triggering the fault code.

This issue is particularly important for used excavators because degraded wiring harnesses and corroded connectors are common culprits that create false high-voltage readings.

Common Symptoms

• Check Engine Light (CEL) or malfunction indicator lamp illuminated on the instrument cluster
• Engine derate or power reduction mode, limiting machine to 70-80% normal output
• Hard starting or extended cranking time, especially in cold weather conditions
• Rough idle and inconsistent engine RPM due to incorrect air-fuel mixture calculations
• Black or gray exhaust smoke from improper fuel compensation based on faulty temperature readings

Potential Causes

The most common technical causes for Code E000106-06 on used DX215-9C excavators include:

• Open circuit in IAT sensor wiring harness caused by wire breaks, particularly at flex points near the engine mount or intake manifold
• Corroded or loose electrical connector at the IAT sensor (2-pin connector) due to moisture intrusion or vibration
• Failed IAT sensor with internal resistance breakdown (common after 5,000+ operating hours)
• Damaged sensor ground circuit (shared ground with other intake sensors)
• Chafed wiring rubbing against engine components or frame—known issue near the turbocharger heat shield on this model
• ECM internal fault (rare, but possible in high-hour machines with electrical system stress)

How to Troubleshoot and Fix Code E000106-06 (P1112)

Step 1: Visual Inspection Begin by locating the IAT sensor on the intake manifold (passenger side, post-intercooler). Inspect the 2-pin connector for corrosion, bent pins, or moisture. Check the entire wiring harness from sensor to ECM for visible damage, particularly where harness passes near hot exhaust components or sharp metal edges. On used excavators, pay special attention to wire insulation cracking—a common aging issue.

Step 2: Electrical Testing Disconnect the IAT sensor connector. Using a digital multimeter (DMM), measure resistance across the sensor terminals. At 68°F (20°C), resistance should read approximately 2,400-2,700 ohms (consult service manual for exact specifications). If reading is infinite/open circuit, the sensor has failed. Next, check voltage at the harness connector (engine side) with ignition ON: you should see approximately 5.0 volts on the signal wire. If voltage is absent, trace wiring back to ECM.

Step 3: Ground Circuit Verification Test continuity between the sensor ground pin and chassis ground. Resistance should be less than 5 ohms. High resistance indicates corroded ground connections—common in used machines exposed to moisture.

Step 4: Harness Continuity Check With sensor disconnected, check continuity from sensor connector pins to ECM connector terminals (consult wiring diagram for pin numbers). Any open circuit indicates broken wiring requiring repair or harness replacement.

Step 5: Component Replacement If sensor tests faulty, replace with OEM Doosan IAT sensor (Part #2872164 or equivalent). After replacement, clear codes using Doosan G-Scan diagnostic software or compatible scan tool. Road test and monitor for code recurrence.

Critical Note for Used Equipment: Before replacing expensive ECM components, always verify physical wiring integrity and connector condition—over 70% of sensor codes in used excavators stem from wiring issues, not actual sensor failure.

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Disclaimer: This guide provides general diagnostic information. Always consult the official Doosan DX215-9C service manual and consider professional diagnostic support for complex electrical issues. Improper repairs may cause additional engine damage or void warranties.