What is Case CX220C Fault Code 7248?

Fault Code 7248 on the Case CX220C excavator indicates a hydraulic pump solenoid circuit malfunction, specifically an open circuit or electrical discontinuity in the pump control solenoid valve wiring harness. This code is generated by the machine's Electronic Control Module (ECM) when it detects abnormal voltage readings or loss of continuity in the solenoid control circuit that regulates hydraulic pump output.

The Case CX220C uses electronically-controlled variable displacement hydraulic pumps with proportional solenoid valves to optimize flow and pressure based on operational demands. When Code 7248 triggers, the ECM cannot properly modulate pump output, directly impacting the excavator's hydraulic performance and fuel efficiency. This fault is particularly critical because the hydraulic system is the lifeblood of excavator operations—controlling boom, arm, bucket, and swing functions.

Common Symptoms

• Hydraulic system operating in limp mode with significantly reduced flow and sluggish implement response
• Amber warning light illuminated on the instrument cluster with possible fault code display
• Loss of fine control during precision work, as the pump defaults to mechanical backup settings
• Increased engine RPM required to achieve normal hydraulic performance
• Intermittent hydraulic power loss, especially during cold starts or after extended operation

Potential Causes

On used Case CX220C excavators, Code 7248 typically stems from age-related electrical deterioration:

• Damaged wiring harness near the hydraulic pump mounting area where vibration and heat cause insulation breakdown
• Corroded connector pins at the pump solenoid plug, especially on machines operated in wet or marine environments
• Failed pump control solenoid coil (internal open circuit within the solenoid itself)
• Chafed wires at harness routing points near the swing bearing or along the upper structure frame rails—a known wear point on CX-series excavators
• ECM connector issues or corrosion at the controller side of the circuit
• Previous repair attempts using incorrect wire gauge or inadequate splice connections

How to Troubleshoot and Fix Code 7248

Step 1: Visual Inspection Begin with a thorough inspection of the wiring harness from the ECM to the hydraulic pump solenoid. On used excavators, focus on areas where the harness passes through metal brackets or rubs against the frame. Look for abraded insulation, pinched wires, or heat damage near the pump mounting location.

Step 2: Connector Examination Disconnect the solenoid connector at the hydraulic pump. Inspect pins for corrosion, bent contacts, or moisture intrusion—common issues on machines with 3,000+ operating hours. Clean contacts with electrical contact cleaner and apply dielectric grease before reconnection.

Step 3: Electrical Testing Using a digital multimeter, measure solenoid coil resistance across the solenoid terminals (typically 8-15 ohms for Case pumps; consult service manual for exact specification). An infinite reading confirms an open circuit within the solenoid. Next, check for continuity through the entire harness from ECM connector to solenoid plug with the harness disconnected at both ends.

Step 4: Voltage Supply Check With ignition on and harness connected, measure voltage supply at the solenoid connector. You should see battery voltage (12V) on the power supply wire. If voltage is absent, trace back toward the ECM checking for blown fuses, broken wires, or failed relays.

Step 5: Component Replacement If the solenoid tests faulty, replace with a genuine Case OEM solenoid or quality aftermarket equivalent rated for the CX220C's hydraulic system pressure (typically 350+ bar). If harness damage is found, repair using proper gauge wire, heat-shrink connections, and secure routing away from wear points—don't simply tape damaged sections on used machines, as temporary repairs fail quickly.

Step 6: Code Clearing and Verification After repairs, clear the fault code using Case diagnostic software (ServiceMaster or compatible scan tool). Operate the machine through full hydraulic cycles and monitor for code recurrence. On used equipment, perform a complete hydraulic system function test to ensure proper pump modulation is restored.

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Disclaimer: This guide provides general troubleshooting information for Code 7248 on Case CX220C excavators. Hydraulic and electrical system repairs require proper training and tools. Always consult the official Case service manual for your machine's specific serial number range, and consider professional diagnostic assistance for complex electrical issues, especially on used equipment where multiple underlying problems may exist.