Case CX220C Fault Code 113: Technical Guide

What is Case CX220C Fault Code 113?

Case CX220C Fault Code 113 indicates a Hydraulic Pump Pressure Sensor Circuit malfunction, specifically a voltage signal that is out of range or has failed to respond within the Electronic Control Module (ECM) parameters. This diagnostic trouble code triggers when the ECM detects an abnormal voltage reading from the main hydraulic pump pressure sensor, typically outside the expected 0.5-4.5 volt operating range.

This code is critical for the CX220C's performance because the hydraulic pressure sensor provides real-time data that the ECM uses to regulate pump output, control hydraulic flow distribution, and protect the system from over-pressurization. Without accurate pressure readings, the machine may enter a derate mode to prevent component damage, significantly limiting operational capacity and productivity.

Common Symptoms

• Warning light illuminated on the instrument panel with reduced hydraulic power
• Noticeably slower cycle times for boom, arm, and bucket movements
• Engine derate or automatic power reduction to protect hydraulic components
• Intermittent loss of hydraulic functions, particularly under heavy load conditions
• Error message displayed on the monitor indicating hydraulic system fault

Potential Causes

The most common causes of Code 113 on used CX220C excavators include:

• Pressure sensor failure due to internal component degradation or contaminated hydraulic fluid exposure
• Wiring harness damage at known rub points near the hydraulic pump mounting area where vibration causes insulation wear
• Corroded or loose connector pins at the sensor plug, especially on machines with high operating hours in wet or corrosive environments
• ECM internal circuit failure affecting the sensor signal processing pathway
• Voltage supply issues from damaged wiring between the ECM and sensor (typically a 5-volt reference circuit)
• Contaminated hydraulic oil causing sensor membrane damage or incorrect readings

How to Troubleshoot and Fix Code 113

Step 1: Visual Inspection Begin by inspecting the hydraulic pump pressure sensor and its wiring harness for obvious damage. On used excavators, check for wire chafing against the pump housing, heat damage from nearby components, and connector corrosion. Clean all connector pins with electrical contact cleaner and verify secure connections.

Step 2: Electrical Testing Using a digital multimeter, perform voltage checks at the sensor connector. With the key on and engine off, verify the 5-volt reference signal from the ECM. Check sensor ground continuity (should read less than 1 ohm to chassis ground). Measure sensor output voltage—it should read approximately 0.5-1.0 volts at zero pressure.

Step 3: Sensor Resistance Check Disconnect the sensor and measure its internal resistance. Refer to Case service manual specifications, but typical readings range from 100-300 ohms. Readings outside this range indicate sensor replacement is necessary.

Step 4: Harness Continuity Test Test continuity between the sensor connector and ECM pins to identify any open circuits. For used machines, pay special attention to the harness routing near the hydraulic tank where flex fatigue commonly occurs.

Step 5: Hydraulic System Verification Before installing a new sensor, verify hydraulic oil condition and pressure relief valve operation. Contaminated fluid can quickly damage replacement sensors.

Professional Tip: On high-hour used excavators, always replace the connector pigtail along with the sensor, as corrosion inside connector bodies often causes intermittent faults that return after sensor replacement alone.

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Disclaimer: This guide provides general troubleshooting information. Always consult the official Case service manual and consider professional diagnostic assistance for complex electrical issues. Improper repairs may cause additional system damage or safety hazards.