Komatsu PC210-10 Fault Code L01CA698: Technical Guide

What is Komatsu PC210-10 Fault Code L01CA698?

Fault Code L01CA698 indicates a communication error between the machine's Controller Area Network (CAN) system and the hydraulic system controller, specifically related to the pump flow control circuit malfunction. This code is triggered when the machine's Engine Control Module (ECM) detects an abnormal signal or loss of communication with the hydraulic pump controller, which regulates variable pump displacement on the PC210-10's closed-center hydraulic system.

This fault is critical for the PC210-10 because the pump flow control directly manages hydraulic efficiency and power distribution. When communication fails, the excavator may enter a derate mode or operate with reduced hydraulic responsiveness, significantly impacting productivity and fuel efficiency on this 21-ton class machine.

Common Symptoms

When Code L01CA698 is active, operators typically experience:

• Warning light illuminated on the monitor panel with reduced engine power output
• Sluggish hydraulic response during boom, arm, or bucket operations, particularly under load
• Intermittent loss of swing or travel functions due to pump flow restrictions
• Engine RPM fluctuations or inability to reach maximum rated speed (2,000 RPM)
• Error messages displayed on the Komtrax monitor indicating hydraulic system faults

Potential Causes

The most common technical causes for L01CA698 on used PC210-10 excavators include:

• Corroded or damaged CAN bus connectors at the pump controller harness (known wear point behind the hydraulic pump mounting bracket)
• Failed pump solenoid valve or internal proportional control valve within the main hydraulic pump assembly
• Wiring harness damage due to chafing against the engine block or heat shield deterioration (common after 5,000+ operating hours)
• Faulty hydraulic pump controller module with degraded internal circuit boards from moisture intrusion
• ECM software version mismatch or corrupted data following previous repair attempts or battery disconnection
• Voltage supply issues from failing alternator or corroded ground connections at the pump controller

How to Troubleshoot and Fix Code L01CA698

Step 1: Initial Visual Inspection Begin by thoroughly inspecting the hydraulic pump wiring harness for visible damage, particularly where it routes along the engine's right side. On used machines, check for oil contamination on connectors near the pump assembly and examine the CAN bus termination resistor at the controller plug (should measure 60 ohms between CAN-H and CAN-L pins).

Step 2: Electrical Testing Using a digital multimeter, verify power supply voltage at the pump controller connector with the key on (should read 24V DC ±2V). Check ground circuit continuity (less than 1 ohm resistance to chassis ground). For advanced diagnostics, use Komatsu KDPF diagnostic software to monitor real-time CAN bus communication and identify specific message failures.

Step 3: Component Testing and Repair Test the pump solenoid valve resistance (typically 8-12 ohms at room temperature). If readings are abnormal, remove and inspect the proportional valve cartridge for debris or wear. For used excavators, clean all connector pins with electrical contact cleaner and apply dielectric grease before reassembly—many L01CA698 codes resolve after addressing connector corrosion rather than component replacement.

Disclaimer: This guide provides general troubleshooting information. Always consult the official Komatsu service manual for your specific machine serial number and seek professional diagnostic assistance for complex electrical or hydraulic system repairs.