Komatsu PC100-6 Fault Code E213: Technical Guide

What is Komatsu PC100-6 Fault Code E213?

Fault Code E213 indicates a hydraulic oil temperature sensor circuit malfunction in the Komatsu PC100-6 excavator. This diagnostic trouble code (DTC) is triggered when the Electronic Control Module (ECM) detects an abnormal voltage reading from the hydraulic oil temperature sensor, typically indicating an open circuit, short circuit, or sensor failure.

This code is critical for the PC100-6 because the hydraulic system relies on accurate temperature monitoring to prevent overheating and component damage. The ECM uses this sensor data to regulate hydraulic pump output and activate warning systems when oil temperatures exceed safe operating parameters (typically 80-95°C). Ignoring this fault can lead to accelerated wear on hydraulic components, seal degradation, and potential system failure.

Common Symptoms

• Hydraulic oil temperature warning light illuminated on the instrument cluster
• Erratic temperature gauge readings or gauge stuck at minimum/maximum position
• Reduced hydraulic performance or slower cycle times as ECM enters protective derate mode
• Intermittent warning alarms especially during warm-up or under heavy load conditions
• ECM may limit engine RPM to approximately 1,500-1,800 RPM to protect the hydraulic system

Potential Causes

On used PC100-6 excavators, E213 commonly results from age-related deterioration and environmental exposure:

• Corroded or damaged sensor connector located near the hydraulic tank (prone to moisture intrusion)
• Failed hydraulic oil temperature sensor due to thermal cycling and oil contamination over years of operation
• Wiring harness abrasion at known rub points near the swing motor or along the main chassis harness
• Poor ground connection at the sensor mounting location due to paint buildup or corrosion
• ECM internal fault (less common) affecting the sensor input circuit
• Aftermarket sensor replacement with incorrect resistance specifications

How to Troubleshoot and Fix Code E213

Step 1: Visual Inspection Locate the hydraulic oil temperature sensor (typically mounted on the hydraulic tank or return line). Inspect the sensor connector for corrosion, bent pins, or oil contamination. On used machines, check for harness chafing against metal edges, especially where the harness passes through the swing bearing area.

Step 2: Electrical Testing Disconnect the sensor connector. Using a digital multimeter, measure sensor resistance at various temperatures. A functioning sensor should show approximately 2.5-3.0 kΩ at 20°C and decrease as temperature rises. Check wiring continuity from sensor to ECM (Pin 23 on most PC100-6 ECMs). Verify less than 1Ω resistance in the circuit.

Step 3: Voltage Testing With ignition on and sensor disconnected, measure reference voltage at the sensor connector (should read approximately 5V DC). If voltage is absent, trace wiring back to the ECM checking for breaks or shorts to ground.

Step 4: Component Replacement If sensor tests outside specifications, replace with genuine Komatsu parts (Part #7861-93-3320 or equivalent). Clean the mounting surface thoroughly and apply anti-seize compound to threads. For used excavators, consider replacing the connector pigtail simultaneously if corrosion is present, as this prevents recurring failures.

Step 5: Clear Code and Verify After repairs, clear the fault code using Komatsu diagnostic software (KOMTRAX) or a compatible scan tool. Operate the machine through a complete warm-up cycle and monitor oil temperature readings to confirm repair.

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Disclaimer: This guide provides general troubleshooting information. Hydraulic and electrical system repairs should be performed by qualified technicians following manufacturer service procedures. Always consult the Komatsu PC100-6 service manual and use appropriate safety equipment when diagnosing electrical systems.