What is Komatsu PC210-10 Fault Code CA698?

Fault Code CA698 indicates a CAN communication error between the Engine Controller (ECM) and the Machine Controller (MC) on the Komatsu PC210-10 excavator. This diagnostic trouble code (DTC) is triggered when the Controller Area Network (CAN) bus experiences interrupted or degraded data transmission between these two critical control modules.

The CAN bus system serves as the digital nervous system for modern excavators, allowing the engine management system to communicate with the machine's hydraulic controls, monitoring systems, and operator interface. When CA698 activates, the ECM cannot properly relay engine performance data to the MC, which may result in reduced machine functionality or protective operating modes. For the PC210-10 model specifically, this communication link is essential for coordinating fuel management, emissions controls, and hydraulic demand with actual engine output.

Common Symptoms

• Warning lights: The engine malfunction lamp and monitor panel warning indicators illuminate simultaneously on the operator display
• Reduced hydraulic performance: Machine enters a derate mode with noticeably slower cycle times and diminished boom/arm/bucket response
• Intermittent power loss: Engine may experience momentary hesitation or irregular RPM fluctuations during operation
• Dashboard communication errors: Multi-function display shows incomplete data or freezes, with missing engine parameters (temperature, fuel rate, etc.)
• Stored fault codes: Multiple secondary codes may appear alongside CA698 related to sensor communication timeouts

Potential Causes

On used excavators like the PC210-10, CA698 typically results from age-related electrical degradation rather than component failure:

• CAN bus wiring harness damage: Harness routing near the turntable bearing experiences repeated flexing, causing internal wire fractures without visible external damage
• Corroded connector pins: The 9-pin CAN-H and CAN-L connections at the ECM or MC develop oxidation, creating high resistance in the communication circuit
• Termination resistor failure: The 120-ohm terminating resistors at each end of the CAN bus network can degrade or lose connection
• ECM or MC internal fault: Less common, but controller internal communication circuits may fail, particularly in machines with 8,000+ operating hours
• Voltage supply issues: Unstable power to either controller (typically 24V nominal) disrupts communication protocol timing

How to Troubleshoot and Fix Code CA698

Step 1: Visual Inspection and Connector Service

Begin with the most common failure points on used equipment. Locate the main CAN bus harness running from the engine compartment through the turntable area to the cab. Inspect for abrasion marks, pinch points, or harness routing that contacts moving components. Disconnect the CAN communication connectors at both the ECM (located on the engine) and MC (typically under the operator's seat). Clean all pins with electrical contact cleaner and inspect for green corrosion, bent pins, or moisture intrusion. Apply dielectric grease before reconnection.

Step 2: CAN Bus Electrical Testing

Using a digital multimeter (DMM), measure the resistance between CAN-H and CAN-L terminals with both controllers disconnected. You should read approximately 60 ohms, indicating both 120-ohm termination resistors are intact and properly connected. Next, check continuity of each individual wire from ECM to MC—any reading above 2 ohms indicates internal harness damage. With the ignition on (engine off), measure voltage between CAN-H and CAN-L at each controller; you should see approximately 2.5V DC at idle state, fluctuating during communication attempts.

Step 3: Advanced Diagnostics and Component Replacement

Connect Komatsu KOMTRAX diagnostic software or a compatible J1939 CAN bus scanner to monitor live communication data. Observe message traffic between ECM and MC—intermittent dropouts or complete communication loss confirms harness or controller issues. If harness testing passes but communication fails, individually swap ECM and MC controllers (if spare units are available) to isolate the faulty module. For used excavators, replacing the entire CAN harness through the turntable is often more cost-effective than intermittent troubleshooting, as internal wire damage is difficult to locate precisely.

Critical for Used Equipment: Before replacing expensive controllers, thoroughly inspect harness grommets where wiring passes through metal panels—these friction points are notorious failure locations on machines with 5,000+ hours.

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Disclaimer: This guide provides general troubleshooting information for experienced technicians. Always consult the official Komatsu PC210-10 Service Manual and follow manufacturer-specific procedures. If you lack proper diagnostic tools or training, seek assistance from a certified Komatsu dealer or qualified heavy equipment technician.