What is XCMG XE750D Fault Code E1045(2) SPN102 FMI18?

Fault Code E1045(2) with SPN102 FMI18 indicates a data erratic or intermittent signal issue with the Boost Pressure (Turbocharger Intake Manifold Pressure) sensor circuit on the XCMG XE750D excavator. This code follows J1939 diagnostic standards where SPN 102 specifically monitors intake manifold pressure, and FMI 18 signals data that is valid but updating abnormally or erratically.

This fault directly affects the Engine Control Module's (ECM) ability to manage fuel delivery, turbocharger boost control, and overall engine performance. On the XE750D's diesel engine system, accurate boost pressure readings are critical for maintaining optimal power output, fuel efficiency, and emissions compliance. When the ECM receives inconsistent pressure data, it cannot properly adjust injection timing or air-fuel ratios, potentially leading to reduced machine productivity and increased fuel consumption.

Common Symptoms

• Check Engine Light (CEL) illuminated on the instrument cluster with reduced engine power
• Engine derate mode activated, limiting maximum RPM to 1500-1800 range to protect the powertrain
• Black smoke from exhaust during acceleration due to improper air-fuel mixture calculations
• Intermittent power loss or surging during heavy digging operations when boost demand is highest
• Turbocharger wastegate may cycle erratically, causing unusual whistling or flutter sounds

Potential Causes

The most common technical causes for this specific code on used XCMG excavators include:

• Corroded or loose connector pins at the boost pressure sensor—this three-pin connector is exposed to engine bay heat cycling and moisture intrusion
• Damaged sensor wiring harness rubbing against the intake manifold or turbocharger heat shield (known wear point on XE750D models with 8,000+ operating hours)
• Failing MAP/boost pressure sensor with internal circuit degradation causing intermittent resistance values
• Contaminated sensor port with carbon buildup or oil residue blocking the pressure reference line
• ECM software calibration issues requiring firmware updates specific to later XE750D production runs
• Poor ground connection at engine block grounding points due to corrosion or loose mounting bolts

How to Troubleshoot and Fix Code E1045(2) SPN102 FMI18

Step 1: Visual Inspection and Connector Check Begin by locating the boost pressure sensor mounted on the intake manifold near the turbocharger outlet. With the engine off and cool, disconnect the three-pin connector and inspect for corrosion, bent pins, or moisture. On used excavators, check the entire wiring harness from sensor to ECM for chafing against metal edges—the harness routing near the engine lifting bracket is a common failure point on XE750D models.

Step 2: Electrical Testing with Multimeter Using a digital multimeter (DMM), backprobe the sensor connector with the ignition ON, engine OFF. Verify 5-volt reference supply (typically pin 1) and solid ground signal (pin 2) from the ECM. Measure sensor output voltage (pin 3) at atmospheric pressure—it should read approximately 0.5-1.0 volts. Any reading outside this range or fluctuating more than 0.1V indicates sensor failure. Check harness continuity to ECM and verify resistance is below 5 ohms on all circuits.

Step 3: Sensor Port and Physical Component Inspection Remove the boost pressure sensor and inspect the threaded port for carbon deposits or oil contamination. Clean with brake cleaner and compressed air. For used machines with high hours, replace the sensor O-ring seal. If electrical tests passed but the code persists, the sensor's internal piezoresistive element may be failing intermittently under heat or vibration—replacement is necessary. After repairs, clear codes using XCMG diagnostic software or compatible J1939 scan tool, then perform a boost pressure test under load to verify stable readings.

Disclaimer: This guide provides general troubleshooting procedures. Always consult the XCMG XE750D service manual for model-specific specifications. If you're unfamiliar with high-voltage electrical systems or lack proper diagnostic tools, seek assistance from a certified heavy equipment technician to prevent injury or further machine damage.