What is Komatsu PC210LC-10 Fault Code DWK2KA?

Fault Code DWK2KA indicates a communication error between the machine monitor and the hydraulic system controller (HSC) on the Komatsu PC210LC-10 excavator. This code specifically signals a CAN (Controller Area Network) bus communication failure or disruption in the data exchange between the main monitoring system and the hydraulic control unit.

The PC210LC-10 relies heavily on integrated electronic systems to manage hydraulic performance, fuel efficiency, and operator interface functions. When the machine monitor cannot properly communicate with the HSC, the excavator's ability to optimize hydraulic flow, track operating parameters, and display critical machine data becomes compromised. This fault is particularly significant in this model because the Dash-10 series introduced enhanced electronic integration, making reliable CAN bus communication essential for proper machine operation.

Common Symptoms

When fault code DWK2KA is active, operators typically experience:

• Warning light illumination on the dashboard with potential display of the fault code on the monitor screen
• Intermittent or complete loss of hydraulic system data on the monitor (temperatures, pressures, flow rates)
• Reduced machine performance or entry into derate mode where hydraulic response becomes sluggish
• Inability to access certain monitor functions, settings, or diagnostic information through the cab display
• Erratic gauge readings or complete monitor screen freezing/blanking in severe cases

Potential Causes

The most common technical reasons for DWK2KA appearing on used PC210LC-10 excavators include:

• Damaged or corroded CAN bus wiring harness connections between the monitor and HSC, especially at connectors near the cab floor or along the boom base where harness routing experiences flexing
• Failed hydraulic system controller (HSC) unit due to age, moisture intrusion, or voltage spikes
• Faulty machine monitor display unit with internal communication circuit failure
• Poor ground connections at either the monitor or HSC mounting points, common in machines with 3,000+ operating hours
• Corroded or loose connector pins at the 24-pin HSC connector (C-303) or monitor backside connectors, typical in machines operated in high-moisture environments
• CAN bus termination resistor failure within either control module

How to Troubleshoot and Fix Code DWK2KA

Step 1: Visual Inspection of Harness and Connectors

Begin by inspecting the CAN bus wiring harness running from the cab monitor to the HSC located near the hydraulic pump area. On used excavators, check specifically for harness chafing against the cab frame, pinched wires near the door hinge area, and connector corrosion at both ends. Disconnect and inspect the 24-pin connector (C-303) at the HSC and the corresponding monitor connectors—look for green corrosion, bent pins, or moisture. Clean connections with electrical contact cleaner and apply dielectric grease before reconnecting.

Step 2: Test CAN Bus Communication with Diagnostic Tools

Using Komatsu KOMTRAX diagnostic software or a compatible CAN bus analyzer, check for active communication on the CAN High and CAN Low lines between the monitor and HSC. With a digital multimeter, measure resistance between CAN High (typically yellow wire) and CAN Low (typically green wire) at the HSC connector—you should read approximately 60 ohms with both modules connected (indicating proper termination resistors). Infinite resistance suggests an open circuit in the harness, while very low resistance indicates a short circuit.

Step 3: Check Power Supply and Grounds

Verify that both the machine monitor and HSC are receiving proper 24V DC power supply using your multimeter. Check voltage at the power pins (refer to the PC210LC-10 electrical schematic for specific pin locations). More importantly for used machines, test the ground connections—measure voltage drop between the negative battery terminal and the ground pins at each module. A reading above 0.2V indicates poor ground contact, which can cause intermittent communication failures. Clean and tighten all ground points, ensuring metal-to-metal contact.

Step 4: Perform Module Isolation Testing

If harness and connections test good, isolate which module is faulty by substitution testing if possible. The HSC failure rate is higher than monitor failures on these machines. Before replacing components on a used excavator, consider that connector corrosion and harness wear account for approximately 70% of communication faults. Inspect the harness routing through the cab floor grommet and along the swing post—these are known wear points where the harness can develop internal wire breaks while the outer insulation appears intact.

Professional Disclaimer: While this guide provides technical troubleshooting steps, complex electrical diagnostics on heavy equipment should be performed by qualified technicians with proper diagnostic tools and access to manufacturer service literature. Improper diagnosis can lead to costly part replacement without resolving the underlying issue.