What is Komatsu PC200-8M0 Fault Code DWA2KA?

Fault Code DWA2KA on the Komatsu PC200-8M0 excavator indicates a communication error or abnormal signal detected in the machine monitoring system's CAN (Controller Area Network) data link between the main controller and auxiliary control modules. This diagnostic trouble code specifically points to disrupted data transmission within the excavator's electronic network, affecting the machine's ability to monitor and control critical operational parameters.

This code is particularly significant for the PC200-8M0 model because it utilizes an integrated KOMTRAX Plus monitoring system that relies on constant communication between the Engine Control Module (ECM), Pump Control Module, and the Main Monitor Display. When this network communication fails, the excavator cannot accurately monitor engine parameters, hydraulic system performance, or implement proper safety protocols, potentially leading to reduced machine protection and operational inefficiencies.

Common Symptoms

When fault code DWA2KA is active on your Komatsu PC200-8M0, operators typically experience:

• Intermittent or complete failure of the main monitor display showing erratic readings or blank screens
• Warning indicators flashing simultaneously on the dashboard without corresponding machine malfunctions
• Loss of real-time data including fuel consumption, operating hours, or hydraulic temperature readings
• Erratic hydraulic response or unexplained power limitations despite no mechanical issues
• KOMTRAX system failing to transmit operational data to remote monitoring platforms

Potential Causes

The most common technical causes for DWA2KA in used PC200-8M0 excavators include:

• CAN bus wiring harness damage from rubbing against the chassis near the cab floor mounting points or along the right-side engine compartment bulkhead (known wear point on this model)
• Corroded or loose connector pins at the main monitor harness connection behind the operator seat
• Failed termination resistor in the CAN network circuit (typically 120-ohm resistance failure)
• Water intrusion into the central junction box located under the cab floor, common in machines with cab seal deterioration
• ECM or monitor module internal failure due to voltage spikes or age-related component degradation
• Aftermarket accessory installation that improperly tapped into the CAN network without proper isolation

How to Troubleshoot and Fix Code DWA2KA

Step 1: Visual Inspection of Harness and Connectors Begin by thoroughly inspecting the CAN bus wiring harness routing from the ECM through the cab junction box to the main monitor. On used PC200-8M0 excavators, pay special attention to the harness section running along the right engine compartment wall where vibration causes insulation wear. Check all multi-pin connectors for corrosion (green/white deposits), bent pins, or moisture intrusion. Clean connectors with electrical contact cleaner and apply dielectric grease before reconnection.

Step 2: CAN Network Resistance Testing Using a digital multimeter, measure the resistance across the CAN-High and CAN-Low terminals at the ECM connector with all modules connected and ignition off. You should read approximately 60 ohms (two 120-ohm terminating resistors in parallel). A reading significantly higher suggests an open circuit or failed termination resistor; a reading near zero indicates a short circuit within the network. For used excavators, also check individual harness sections for resistance changes that indicate internal wire damage from repeated flexing.

Step 3: Module Communication Verification Connect Komatsu diagnostic software (KTEC) or a compatible diagnostic tool to the service port. Monitor live CAN bus traffic to identify which specific module is failing to communicate. Check voltage supply to all modules—should be steady 24V DC. Inspect the central junction box under the cab floor for water damage or corrosion, as this is a common failure point in older machines. If a specific module (monitor, ECM, or pump controller) shows no communication, test its individual power and ground circuits before condemning the module itself.

Step 4: Verify and Clear Code After repairs, clear the fault code using diagnostic software and operate the machine through various functions for at least 20 minutes. Monitor for code reoccurrence. In used equipment, intermittent codes often indicate harness chafing that requires rerouting or additional protective sleeving rather than component replacement.

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Disclaimer: This guide provides general troubleshooting information for experienced technicians. Always consult the official Komatsu service manual for your specific serial number range and follow proper lockout/tagout procedures. If you're uncomfortable performing electrical diagnostics on high-voltage systems, consult a certified Komatsu dealer or qualified heavy equipment technician.