Sumitomo SH220LC-6 Fault Code 217: Complete Diagnostic Guide

What is Sumitomo SH220LC-6 Fault Code 217?

Fault Code 217 on the Sumitomo SH220LC-6 excavator indicates a malfunction in the hydraulic oil temperature sensor circuit or an abnormal high-temperature reading in the hydraulic system. This code is triggered when the Electronic Control Module (ECM) detects either an electrical fault in the sensor wiring or actual hydraulic oil temperatures exceeding safe operating parameters (typically above 95°C/203°F).

This code is critical for the SH220LC-6 because excessive hydraulic temperatures can cause rapid degradation of seals, accelerated fluid breakdown, and potential damage to the hydraulic pump and control valves. The machine's monitoring system uses this sensor to protect expensive hydraulic components from thermal damage, making accurate temperature readings essential for component longevity.

Common Symptoms

When Code 217 is active on your SH220LC-6, operators typically experience:

• Warning light illuminated on the instrument cluster (typically amber or red hydraulic temperature indicator)
• Noticeable reduction in hydraulic system responsiveness or sluggish boom/arm movements
• Audible alarm sounding in the cab when temperatures exceed threshold
• Potential automatic derate of engine power to reduce hydraulic load
• Visible smoke or burning smell from the hydraulic tank area in severe cases

Potential Causes

The most common technical causes for Code 217 on used SH220LC-6 excavators include:

• Hydraulic oil temperature sensor failure due to age-related internal component degradation
• Damaged or corroded wiring harness at sensor connector (common rubbing point near hydraulic tank mounting bracket)
• Short circuit or open circuit in sensor wiring from vibration-induced wire breakage
• Actual hydraulic system overheating from clogged hydraulic oil cooler fins or failed cooling fan
• Low hydraulic oil level causing insufficient heat dissipation
• ECM calibration issues or software glitches in older machines
• Failed hydraulic pump creating excessive heat from internal wear

How to Troubleshoot and Fix Code 217

Step 1: Initial Visual Inspection Begin by checking hydraulic oil level and condition. Inspect the hydraulic oil cooler for debris blockage and verify the cooling fan operates properly. On used excavators, examine the sensor wiring harness for obvious damage, particularly where it routes near the hydraulic tank—this is a known wear point on the SH220LC-6.

Step 2: Sensor and Circuit Testing Using a digital multimeter, disconnect the temperature sensor connector and measure resistance across the sensor terminals. At 20°C (68°F), resistance should typically read between 2,000-3,000 ohms (consult service manual for exact specifications). Check for continuity in the wiring harness from sensor to ECM. Inspect connector pins for corrosion or bent terminals—common issues in used machines exposed to moisture.

Step 3: Advanced Diagnostics Connect Sumitomo diagnostic software or compatible scan tool to read live sensor data. Compare actual hydraulic temperature (measured with infrared thermometer) against displayed values. Replace the sensor if readings are erratic or frozen. If wiring shows damage, repair or replace the entire harness section rather than splicing—critical for preventing future failures.

Step 4: System Verification After repairs, clear codes and operate the machine through full work cycles. Monitor temperatures during heavy load conditions to ensure proper sensor operation and verify no actual overheating exists.

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Disclaimer: This guide provides general diagnostic information. Always consult the official Sumitomo service manual for your specific machine serial number. If you're uncomfortable with electrical diagnostics or the issue persists, contact a certified Sumitomo technician or qualified heavy equipment mechanic.