Sumitomo SH240-6 Fault Code 1113: Complete Diagnostic Guide

What is Sumitomo SH240-6 Fault Code 1113?

Fault Code 1113 on the Sumitomo SH240-6 excavator indicates a Low Intake Manifold Pressure Sensor signal error, specifically detecting an abnormally low voltage reading from the boost pressure sensor circuit. This code triggers when the Engine Control Module (ECM) receives a signal below the manufacturer's specified threshold, typically under 0.5 volts, from the intake manifold pressure sensor (also called the boost pressure sensor or MAP sensor).

This sensor is critical for the SH240-6's turbocharged diesel engine performance. The ECM relies on accurate intake pressure data to calculate optimal fuel injection timing, turbocharger boost control, and air-fuel ratios. When this sensor malfunctions, the engine cannot properly adjust to load conditions, resulting in significant power loss and inefficient combustion.

Common Symptoms

When Code 1113 is active on your Sumitomo SH240-6, you may experience:

• Engine derate mode with noticeable power reduction, especially under heavy digging loads
• Check engine light or malfunction indicator illuminated on the instrument panel
• Poor throttle response and sluggish acceleration when operating hydraulics
• Black smoke from exhaust due to incorrect fuel mapping
• Rough idle or unstable engine RPM at low speeds

Potential Causes

The most common technical causes for Code 1113 on used SH240-6 excavators include:

• Damaged or corroded sensor connector at the intake manifold—a frequent issue on machines with 5,000+ operating hours
• Broken signal wire in the harness between the sensor and ECM, particularly where the harness passes near the engine mount (known rub point on this model)
• Failed intake manifold pressure sensor due to internal circuit degradation or membrane rupture
• Shorted sensor ground circuit caused by harness chafing against frame components
• Contaminated sensor port blocked by oil vapor, carbon buildup, or debris in older machines
• ECM internal fault (rare, but possible in high-hour units)

How to Troubleshoot and Fix Code 1113

Step 1: Visual Inspection Begin by locating the intake manifold pressure sensor on the intake plenum. Inspect the electrical connector for corrosion, bent pins, or moisture intrusion—common on used excavators stored outdoors. Check the vacuum/pressure hose connected to the sensor for cracks, disconnection, or oil contamination.

Step 2: Electrical Testing Using a digital multimeter, backprobe the sensor connector with the ignition ON, engine OFF. Verify reference voltage from the ECM (should read 4.5-5.2 volts on the signal wire). Check ground continuity (should read less than 0.5 ohms to chassis ground). Measure sensor output voltage at idle—it should read approximately 1.0-1.5 volts at atmospheric pressure.

Step 3: Harness Inspection for Used Machines On older SH240-6 excavators, carefully trace the sensor wiring harness from the sensor to the ECM, paying special attention to areas where the harness contacts the engine block, frame rails, or hydraulic lines. Look for wire insulation wear, exposed copper, or heat damage. This is critical in used equipment where vibration causes accelerated harness deterioration.

Step 4: Component Replacement If voltage readings are incorrect, replace the intake manifold pressure sensor with a genuine Sumitomo or OEM-equivalent part. After installation, clear codes using diagnostic software compatible with Sumitomo excavators (such as dealer-level tools or compatible aftermarket scanners). Test operation under load to confirm repair.

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Disclaimer: This guide provides general troubleshooting information for experienced technicians. Always consult the official Sumitomo service manual for your specific machine serial number and software version. If unfamiliar with diesel engine electronics or high-pressure systems, seek assistance from a certified heavy equipment technician to avoid injury or further damage.