Komatsu PC210LC-7 Fault Code E-13: Technical Guide

What is Komatsu PC210LC-7 Fault Code E-13?

Fault Code E-13 on the Komatsu PC210LC-7 indicates a hydraulic oil temperature sensor circuit malfunction or abnormally high hydraulic oil temperature detected by the machine's monitoring system. This code is triggered when the Electronic Control Unit (ECU) receives signals outside the normal operating parameters from the hydraulic oil temperature sensor, typically indicating readings above 110°C (230°F) or detecting an open/short circuit in the sensor wiring.

This fault is critical for the PC210LC-7 because excessive hydraulic oil temperature can lead to rapid degradation of hydraulic fluid, seal failure, and potentially catastrophic pump damage. The machine's monitoring system uses this sensor data to protect expensive hydraulic components and maintain optimal system viscosity for precise control.

Common Symptoms

When Code E-13 is active on your Komatsu PC210LC-7, operators typically experience:

• Warning light illuminated on the monitor panel, often accompanied by an audible alarm
• Reduced hydraulic response or sluggish boom/arm/bucket movements as the system enters protective derate mode
• Visible temperature gauge reading abnormally high (in the red zone)
• Machine may enter limp mode, limiting travel speed and hydraulic functions to prevent damage
• Unusual hydraulic oil odor (burnt smell) if temperature is genuinely elevated

Potential Causes

The most common technical causes for E-13 on used PC210LC-7 excavators include:

• Faulty hydraulic oil temperature sensor – common failure point after 5,000+ hours, especially on machines operating in dusty/corrosive environments
• Damaged or corroded wiring harness at the sensor connector near the hydraulic tank (known rub point against frame)
• Genuinely overheated hydraulic system due to clogged oil cooler fins, failed cooling fan, or restricted airflow
• Low hydraulic oil level causing insufficient cooling capacity
• Contaminated hydraulic oil with wrong viscosity reducing heat dissipation efficiency
• ECU software glitch or poor ground connection at the controller (less common but possible on older machines)

How to Troubleshoot and Fix Code E-13

Step 1: Initial Visual Inspection Before accessing diagnostic tools, check the hydraulic oil level through the sight glass and inspect the oil cooler for debris blockage. On used excavators, accumulated dirt between cooler fins is a frequent culprit. Clean thoroughly with compressed air from the inside out.

Step 2: Sensor and Wiring Verification Locate the hydraulic oil temperature sensor (typically mounted on the side of the hydraulic tank). Disconnect the sensor connector and inspect for:

• Corroded pins or moisture intrusion (common on high-hour machines)
• Damaged wiring insulation where harness passes near sharp edges
• Using a digital multimeter, measure sensor resistance at room temperature (should read approximately 200-400 ohms at 20°C; consult service manual for exact specs)

Step 3: Circuit Testing With the sensor disconnected and ignition on, measure voltage at the ECU side of the harness connector. You should see approximately 5 volts reference voltage. No voltage indicates wiring break or ECU issue. Check continuity between sensor ground pin and machine chassis ground.

Step 4: Monitor Actual Temperature If wiring checks pass, use Komatsu diagnostic software (KOMTRAX or dealer-level KPSS) to view live hydraulic temperature data. Compare against an infrared thermometer reading taken directly on the hydraulic tank. A discrepancy over 10°C confirms sensor failure.

Step 5: Address Root Cause For used excavators specifically, replace the sensor only after verifying genuine overheating isn't occurring. Check:

• Hydraulic pump case drain flow (excessive flow indicates worn pump)
• Relief valve settings (improper pressure causes heat generation)
• Hydraulic filter condition (restriction increases system temperature)

Replace sensors with genuine Komatsu parts (part number 7861-93-3320) to ensure proper ECU communication. When installing, apply dielectric grease to connector pins to prevent future corrosion.

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Disclaimer: This guide provides general troubleshooting information for Code E-13. Hydraulic systems operate under extreme pressure and temperature. Always consult the official Komatsu PC210LC-7 service manual and consider professional diagnostic assistance, especially when dealing with used equipment where multiple degraded components may contribute to fault conditions.