What is Case CX220C Fault Code 1404?

Fault Code 1404 on the Case CX220C excavator indicates a malfunction in the Boom Raise Solenoid Circuit, specifically detecting an open circuit or abnormal electrical resistance in the solenoid valve that controls boom lifting operations. This code is generated by the machine's Electronic Control Module (ECM) when it detects voltage readings outside the expected range (typically 0.5-4.5V) in the boom raise hydraulic solenoid circuit.

This fault is critical for the CX220C because the boom raise function is fundamental to excavation operations. The proportional solenoid valve regulates hydraulic flow to the boom cylinder, and any electrical disruption prevents proper boom control. Left unaddressed, this code can lead to complete loss of boom function, forcing costly downtime on job sites.

Common Symptoms

• Boom lift function becomes inoperative or sluggish, with the operator unable to raise the boom smoothly or at all
• Amber warning light illuminated on the instrument cluster with potential audible alarm
• Error message displayed on the multi-function monitor showing code 1404
• Intermittent boom operation where function works sporadically before failing completely
• No hydraulic pressure to the boom raise circuit despite other functions operating normally

Potential Causes

The most common causes for Code 1404 on used CX220C excavators include:

• Damaged wiring harness along the right-hand chassis rail where cables run near the boom pivot point—a known wear area on this model
• Corroded or loose connector pins at the boom solenoid valve connection point, especially on machines with high hour counts
• Failed boom raise solenoid coil due to moisture intrusion or internal coil breakdown (resistance should measure 8-15 ohms)
• Chafed wires behind the operator cab where harnesses flex during swing operations
• ECM internal fault (rare) causing false code generation
• Damaged solenoid valve connector from impact or vibration damage during operation

How to Troubleshoot and Fix Code 1404

Step 1: Visual Inspection Begin by inspecting the wiring harness from the ECM to the boom raise solenoid valve. On used CX220C excavators, check the harness routing along the chassis and near hydraulic lines for abrasion, cuts, or oil contamination. Disconnect the solenoid connector and examine pins for corrosion or bent terminals.

Step 2: Electrical Testing Using a digital multimeter, measure the solenoid coil resistance at the valve connector (harness side disconnected). You should read between 8-15 ohms. Next, check for continuity in the wiring from the ECM connector to the solenoid—no breaks should exist. Measure supply voltage at the solenoid connector with ignition on; it should show battery voltage (12V).

Step 3: Component Testing and Repair If resistance is out of spec, replace the boom raise solenoid valve. If wiring shows damage, repair or replace the affected harness section, ensuring proper routing away from heat and friction points. Clear the code using Case diagnostic software (ServiceMaster or compatible scan tool) and cycle the boom function multiple times to verify repair.

For used excavators specifically, always inspect connector seals and apply dielectric grease to prevent future corrosion, as older machines often have compromised weatherproofing.

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Disclaimer: This guide provides general troubleshooting information. Always consult the Case CX220C service manual and consider professional diagnostic assistance for complex electrical issues. Improper repairs may cause further damage or safety hazards.